Items where Author is "Department for Communities and Local Government, "
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a1 loading
NOTES:
1.In assembly buildings (purpose group 5), a gallery is included as a storey, but not if it is a loading gallery, fly gallery, stage grid, lighting bridge, or any gallery provided for similar purposes, or for maintenance and repair.
2.In other purpose group buildings, galleries are not counted as a storey.
3.For the definition of basement, see Appendix A.
NOTES:
For single storey buildings, the periods under the heading ‘Up to 5’ apply. If single storey buildings have basements, for the basement storeys the period appropriate to their depth applies.
* For the floor over a basement or, if there is more than one basement, the floor over the topmost basement, the higher of the period for the basement storey and the period for the ground or upper storey applies.
† For compartment walls that separate buildings, the period is increased to a minimum of 60 minutes.
+ For any floor that does not contribute to the support of the building within a flat of more than one storey, the period is reduced to 30 minutes.
§ For flat conversions, refer to paragraphs 6.5 to 6.7 regarding the acceptability of 30 minutes.
‡ For elements that do not form part of the structural frame, the period is reduced to 90 minutes.
# For elements that protect the means of escape, the period is increased to 30 minutes.
1. Refer to note 1, Table B3 for the specific provisions of test.
2. Blocks of flats with a floor more than 30m above ground level should be fitted with a sprinkler system in accordance with Appendix E.
NOTE:
Sprinklers only need to be provided within the individual flats, they are not required in the common areas such as stairs, corridors or landings when these areas are fire sterile.
3.‘With sprinkler system’ means that the building is fitted throughout with an automatic sprinkler system in accordance with Appendix E.
4. Very large (over 18m in height or with a 10m deep basement) or unusual dwellinghouses are outside the scope of the guidance provided with regard to dwellinghouses.
5. A minimum of 30 minutes in the case of three storey dwellinghouses, increased to 60 minutes minimum for compartment walls separating buildings.
6. Buildings within the ‘office’, ‘shop and commercial’, ‘assembly and recreation’, ‘industrial’ and ‘storage and other non-residential’ (except car parks for light vehicles) purpose groups (purpose groups 3 to 7(a)) require sprinklers where there is a top storey above 30m.
The sprinkler system should be provided in accordance with Appendix E.
7. The car park should comply with the relevant provisions in the guidance on requirement B3, Section 11 of
Approved Document B Volume 2.
8. For the purposes of meeting the Building Regulations, the following types of steel elements are deemed to have satisfied the minimum period of fire resistance of 15 minutes when tested to the European test method.
i. Beams supporting concrete floors, maximum Hp/A=230m-1 operating under full design load.
ii. Free-standing columns, maximum Hp/A=180m-1 operating under full design load.
iii. Wind bracing and struts, maximum Hp/A=210m-1 operating under full design load.
Guidance is also available in BS EN 1993-1-2.
NOTE: Projections from the building line, such as a canopy or a loading platform, can be ignored when assessing separation distance. This does not apply where the canopy is enclosed by side walls.
Distance to relevant boundary measured from building line
See para 11.12
Because the use of buildings may change, a precise estimate of fire severity based on the fire load due to a particular use may be misleading. Therefore if a fire engineering approach of this kind is adopted, the likelihood that the fire load may change in the future needs to be considered.
absorption coefficient
NOTE:
1.Wallcoverings which conform to BS EN 15102, achieving at least class C-s3, d2 and bonded to a class A2-s3, d2 substrate, will also be acceptable.
NOTES:
1. Upper and lower surfaces of suspended ceiling, between plastic panels, to comply with paragraph 4.1.
2. No restriction on class D-s3, d2 diffusers or rooflights in small rooms.
3. See note 4 to Table 4.2. 5m²
See Table 4.2
Cavity barriers are not required between double-skinned corrugated or profiled insulated roof sheeting, if the sheeting complies with all of the following.
a. The sheeting is rated class A2-s3, d2 or better.
b. Both surfaces of the insulating layer are rated class C-s3, d2 or better.
c. Both surfaces of the insulating layer make contact with the inner and outer skins of cladding (Diagram 8.4).
A thermoplastic material alone when used as a lining to a wall or ceiling cannot be assumed to protect a substrate. The surface rating of both thermoplastic material and substrate must therefore meet the required classification. If, however, the thermoplastic material is fully bonded to a non-thermoplastic substrate, then only the surface rating of the composite needs to meet the required classification.
access
For dwellinghouses, access for a pumping appliance should be provided to within 45m of all points inside the dwellinghouse. Every elevation to which vehicle access is provided should have a suitable door(s), not less than 750mm wide, giving access to the interior of the building.
Access routes and hardstandings should comply with the guidance in Table 13.1.
In low rise buildings without deep basements, access for firefighting personnel is typically achieved by providing measures for fire service vehicle access in Section 13 and means of escape.
If the smoke outlet terminates at a point that is not readily accessible, it should be kept unobstructed and covered only with a class A1 grille or louvre.
Final exits should not present a barrier for disabled people. Where the route to a final exit does not include stairs, a level threshold and, where necessary, a ramp should be provided.
A building should provide access to more than one common stair if it does not meet the criteria for a single common stair (see paragraph 3.26 and 3.27).
Access to an external escape stair may be via a flat roof, provided the flat roof meets the requirements of paragraph 3.30.
Access to the fire damper and its actuating mechanism should be provided for inspection, testing and maintenance.
access point
For dwellinghouses, access for a pumping appliance should be provided to within 45m of all points inside the dwellinghouse. Every elevation to which vehicle access is provided should have a suitable door(s), not less than 750mm wide, giving access to the interior of the building.
If the smoke outlet terminates at a point that is not readily accessible, it should be kept unobstructed and covered only with a class A1 grille or louvre.
Fixed ladders should not be provided as a means of escape for members of the public. They should only be provided where a conventional stair is impractical, such as for access to plant rooms which are not normally occupied.
access room
Buildings in which firefighting shafts should be provided,
showing which storeys need to be served >18m >10m
a. Any building The upper storeys in any building with a storey more than 18m above fire service vehicle access level
b. Any building The basement storeys in any building with a basement more than 10m below fire service vehicle access level
c. Any building The basement storey(s) in any building with two or more basements each exceeding 900m2
Fire service vehicle access level
Two or more basement storeys each exceeding 900m2
Extent of firefighting Extent of firefighting lift stair
NOTES:
1.Height excludes any top storey(s) consisting exclusively of plant rooms.
2.Firefighting shafts should serve all floors through which they pass.
See para 15.2
A room accessed only via an inner room (an inner inner room) is acceptable when all of the following apply.
a. It complies with paragraph 2.11.
b. The access rooms each have a smoke alarm (see Section 1).
c. None of the access rooms is a kitchen.
An alternative approach to that described in paragraph 2.21 would be to comply with all of the following.
a. Provide sprinkler protection to the open-plan areas.
b. Provide a fire resisting partition (minimum REI 30) and door (minimum E 20) to separate the ground storey from the upper storeys. The door should allow occupants of the loft room access to a first storey escape window.
c. Separate cooking facilities from the open-plan area with fire resisting construction (minimum REI 30).
Two rooms may be served by a single window. A door between the rooms should provide access to the window without passing through the stair enclosure. Both rooms should have their own access to the internal stair.
NOTES:
1. If travel distance is measured to a stair lobby, the lobby must not provide direct access to any storage room, flat or other space containing a fire hazard.
2. In the case of a small single stair building in accordance with Diagram 3.9, this is reduced to 4.5m.
3. Does not apply if all flats on a storey have independent alternative means of escape.
4. Sheltered housing may require reduced maximum travel distances.
Lift machine rooms should be sited over the lift well where possible. Where buildings or part of a building with only one stairway make this arrangement impractical, the lift machine room should be sited outside the protected stairway.
Two rooms may be served by a single escape window. A door between rooms should provide access to the escape window without passing through the stair enclosure. Both rooms should have their own access to the internal stair.
Where access from any habitable room to the entrance hall or flat entrance is impossible without passing through another room, all of the following conditions should be met (Diagram 3.4).
a. Bedrooms should be separated from living accommodation by fire resisting construction (minimum REI 30) and fire doorsets (minimum E 20).
b. The alternative exit should be in the part of the flat that contains the bedrooms.
When multi-storey flats do not have their own external entrance at ground level, adopt one of the following approaches.
a. Approach 1 – provide at least one alternative exit from each habitable room that is not on the entrance storey of the flat (Diagram 3.5 and paragraph 3.22).
b. Approach 2 – provide at least one alternative exit from each storey that is not the entrance storey of the flat. All habitable rooms should have direct access to a protected landing (Diagram 3.6 and paragraph 3.22).
Approach 3 – provide a protected stairway plus a sprinkler system in accordance with Appendix E (smoke alarms should also be provided in accordance with Section 1).
d. Approach 4 – if the vertical distance between the entrance storey of the flat and any of the storeys above or below does not exceed 7.5m, provide all of the following.
i. A protected stairway.
ii. Additional smoke alarms in all habitable rooms.
iii. A heat alarm in any kitchen.
See paras 3.27 and 3.36
NOTES:
1. The arrangements shown also apply to the top storey.
2. See Diagram 3.9 for small single stair buildings.
3. All doors shown are fire doorsets.
4. Where travel distance is measured to a stair lobby, the lobby must not provide direct access to any storage room, flat or other space containing a potential fire hazard.
5. For further guidance on the fire rating of the fire doorsets from the corridor to the flat and/or stairway refer to Appendix C ,Table C1.
F Flat
Shaded areas indicate zones where ventilation should be provided in accordance with paragraphs 3.50 to 3.53(An external wall vent or smoke shaft located anywhere in the shaded area)
See paras 3.27 and 3.36
NOTES:
1. The arrangements shown also apply to the top storey.
2. See Diagram 3.9 for small single stair buildings.
3. All doors shown are fire doorsets.
4. Where travel distance is measured to a stair lobby, the lobby must not provide direct access to any storage room, flat or other space containing a potential fire hazard.
5. For further guidance on the fire rating of the fire doorsets from the corridor to the flat and/or stairway refer to Appendix C ,Table C1.
F Flat
Shaded areas indicate zones where ventilation should be provided in accordance with paragraphs 3.50 to 3.53(An external wall vent or smoke shaft located anywhere in the shaded area)
A room accessed only via an inner room (an inner inner room) is acceptable when all of the following apply.
a. It complies with paragraph 3.7.
b. The access rooms each have a smoke alarm (see Section 1).
c. None of the access rooms is a kitchen.
Fixed ladders should not be provided as a means of escape for members of the public. They should only be provided where a conventional stair is impractical, such as for access to plant rooms which are not normally occupied.
NOTES:
1. The enclosure should meet all of the following conditions.
a. Be bounded by a compartment wall or floor, an outside wall, an intermediate floor or a casing(see specification at 2 below).
b. Have internal surfaces (except framing members)of class B-s3, d2 or better.
Note: when a classification includes ‘s3, d2’, this means that there is no limit set for smoke production and/or flaming droplets/particles).
c. Not have an access panel which opens into a circulation space or bed room.
d. Be used only for drainage or water supply or vent pipes for a drainage system.
2.The casing should meet all the following conditions.
a. Be imperforate except for an opening for a pipe
or an access panel.
b. Not be of sheet metal.
c. Not have fire resistance less than E 30 (including any access panel).
3.The opening for a pipe, in either the element of structure or the casing, should be as small as possible and fire-stopped around the pipe.
See para 9.4 and Table 9.1
accessible
Access and facilities for the fire service
B5.(1)The building shall be designed and constructed so as to provide reasonable facilities to assist fire fighters in the protection of life.
(2)Reasonable provision shall be made within the site of the building to enable fire appliances to gain access to the building.
For dwellinghouses, access for a pumping appliance should be provided to within 45m of all points inside the dwellinghouse. Every elevation to which vehicle access is provided should have a suitable door(s), not less than 750mm wide, giving access to the interior of the building.
Access routes and hardstandings should comply with the guidance in Table 13.1.
In low rise buildings without deep basements, access for firefighting personnel is typically achieved by providing measures for fire service vehicle access in Section 13 and means of escape.
If the smoke outlet terminates at a point that is not readily accessible, it should be kept unobstructed and covered only with a class A1 grille or louvre.
People should be able to rapidly leave the area around the building. Direct access to a street, passageway, walkway or open space should be available. The route away from the building should comply with the following.
a. Be well defined.
b. If necessary, have suitable guarding.
A building should provide access to more than one common stair if it does not meet the criteria for a single common stair (see paragraph 3.26 and 3.27).
Access to an external escape stair may be via a flat roof, provided the flat roof meets the requirements of paragraph 3.30.
Access to the fire damper and its actuating mechanism should be provided for inspection, testing and maintenance.
accessible entrance
Where access from any habitable room to the entrance hall or flat entrance is impossible without passing through another room, all of the following conditions should be met (Diagram 3.4).
a. Bedrooms should be separated from living accommodation by fire resisting construction (minimum REI 30) and fire doorsets (minimum E 20).
b. The alternative exit should be in the part of the flat that contains the bedrooms.
accessible threshold
Access routes and hardstandings should comply with the guidance in Table 13.1.
Dead-end access routes longer than 20m require turning facilities, as in Diagram 13.1. Turning facilities should comply with the guidance in Table 13.1.
If windows are replaced, it may be necessary to provide cavity barriers around the opening in accordance with Section 5.
See para 2.5
Alternative cavity barrier arrangements in roof space over protected stairway in a house with a storey more than 4.5m above ground level
Final exits should not present a barrier for disabled people. Where the route to a final exit does not include stairs, a level threshold and, where necessary, a ramp should be provided.
Parts of walls in rooms may be of lower performance than stated in Table 4.1, but no worse than class D-s3, d2. In any one room, the total area of lower performance wall lining should be less than an area equivalent to half of the room’s floor area, up to a maximum of 20m2 of wall lining.
Fire doors between the garage and dwellinghouse to have a minimum fire resistance of E30 Sa and be fitted with a self-closing device
Wall and any floor between the garage and dwellinghouse to have a minimum fire resistance of REI 30 from the garage side
The door opening threshold should be a minimum of 100mm above garage floor or
Floor to fall away from door to the outside
See paras 5.6 and 5.7
To reduce the potential for fire spread, cavity barriers should be provided for both of the following.
a. To divide cavities.
b. To close the edges of cavities.
Cavity barriers should not be confused with fire-stopping details (Section 9).
Cavity barriers should be provided at all of the following locations.
a. At the edges of cavities, including around openings (such as windows, doors and exit/entry points for services).
b. At the junction between an external cavity wall and every compartment floor and compartment wall.
c. At the junction between an internal cavity wall and every compartment floor, compartment wall or other wall or door assembly forming a fire resisting barrier.
This does not apply where a wall meets the conditions of Diagram 5.3.
Cavity barriers in a stud wall or partition, or provided around openings, may be formed of any of the following.
a. Steel, a minimum of 0.5mm thick.
b. Timber, a minimum of 38mm thick.
c. Polythene-sleeved mineral wool, or mineral wool slab, under compression when installed in the cavity.
d. Calcium silicate, cement-based or gypsum-based boards, a minimum of 12mm thick.
These do not necessarily achieve the performance specified in paragraph 5.20.
NOTE: Cavity barriers provided around openings may be formed by the window or door frame, if the frame is constructed of steel or timber of the minimum thickness in (a) or (b), as appropriate.
Cavity barriers should be tightly fitted to a rigid construction and mechanically fixed in position. If this is not possible (e.g. where a cavity barrier joins to slates, tiles, corrugated sheeting or similar materials) the junction should be fire-stopped.
Cavity barriers should be fixed so their performance is unlikely to be made ineffective by any of the following.
a. Movement of the building due to subsidence, shrinkage or temperature change, and movement of the external envelope due to wind.
b. During a fire, collapse of services penetrating the cavity barriers, either by the failure of the supporting system or through degradation of the service itself (e.g. by melting or burning).
c. During a fire, failure of the cavity barrier fixings. (In roof spaces, where cavity barriers are fixed to roof members, there is no expectation of fire resistance from roof members provided for the purpose of support.)
d. During a fire, failure of any material or construction to which cavity barriers abut. (For example, a suspended ceiling that continues over a fire resisting wall or partition collapses, and the cavity barrier fails prematurely because the ceiling was not designed to provide a minimum fire resistance of EI 30.)
To reduce the potential for fire spread, cavity barriers should be provided for both of the following.
a. To divide cavities.
b. To close the edges of cavities.
See Diagram 8.1. Cavity barriers should not be confused with fire-stopping details (Section 9).
Cavity barriers should be provided at all of the following locations.
a. At the edges of cavities, including around openings (such as windows, doors and exit/entry points for services).
b. At the junction between an external cavity wall and every compartment floor and compartment wall.
c. At the junction between an internal cavity wall and every compartment floor, compartment wall or other wall or door assembly forming a fire resisting barrier.
This does not apply where a wall meets the conditions of Diagram 8.2.
Cavity barriers are not required between double-skinned corrugated or profiled insulated roof sheeting, if the sheeting complies with all of the following.
a. The sheeting is rated class A2-s3, d2 or better.
b. Both surfaces of the insulating layer are rated class C-s3, d2 or better.
c. Both surfaces of the insulating layer make contact with the inner and outer skins of cladding (Diagram 8.4).
Cavity barriers should meet the requirements set out in paragraphs 5.21 to 5.24.
alternative escape routes
Any external escape stair should meet all of the following conditions (Diagram 2.7).
a. Doors to the stair should be fire resisting (minimum E 30), except for a single exit door from the building to the top landing of a downward-leading external stair.
b. Fire resisting construction (minimum RE 30) is required for the building envelope within the following zones, measured from the flights and landings of the external stair.
i. 1800mm horizontally.
ii. 9m vertically below.
iii. 1100mm above the top landing of the stair (except where the stair leads from basement to ground level).
c. Fire resisting construction (minimum RE 30) should be provided for any part of the building (including doors) within 1800mm of the escape route from the foot of the stair to a place of safety. This does not apply if there are alternative escape routes from the foot of the external escape stair.
d. Stairs more than 6m in height should be protected from adverse weather. Protection should prevent the build-up of snow or ice but does not require full enclosure.
e. Glazing in areas of fire resisting construction should be fixed shut and fire resisting (in terms of integrity, but not insulation) (minimum E 30).
See Diagram 2.1c. The dwellinghouse should have either of the following. Cavity barriers or a fire resisting ceiling (minimum EI 30) should be provided above a protected stairway enclosure (Diagram 2.3). b. Alternative escape route – a top storey separated from lower storeys by fire resisting construction (minimum REI 30) and with an alternative escape route leading to its own final exit.
a. Protected stairway – a stair separated by fire resisting construction (minimum REI 30) at all storeys, that complies with one of the following.
i. Extends to a final exit (Diagram 2.2a).
ii. Gives access to a minimum of two ground level final exits that are separated from each other by fire resisting construction (minimum REI 30) and fire doorsets (minimum E 20) (Diagram 2.2b).
See Diagram 2.1d. In addition to meeting the provisions in paragraph 2.5, the dwellinghouse should comply with either of the following.
a. Provide an alternative escape route from each storey more than 7.5m above ground level. At the first storey above 7.5m, the protected stairway should be separated from the lower storeys by fire resisting construction (minimum REI 30) if the alternative escape route is accessed via either of the following.
i. The protected stairway to an upper storey.
ii. A landing within the protected stairway enclosure to an alternative escape route on the same storey. The protected stairway at or about 7.5m above ground level should be separated from the lower storeys or levels by fire resisting construction (see Diagram 2.4).
b. Provide a sprinkler system throughout, designed and installed in accordance with BS 9251.
NOTES:
1. This diagram does not apply where the gallery is provided with one of the following:
i. An alternative escape route
ii. An emergency escape window (where the gallery floor is not more than 4.5m above ground level).
2. Any cooking facilities within a room containing a gallery should comply with one of the following conditions:
i. Be enclosed with fire resisting construction
ii. Be remote from the stair to the gallery and positioned such that they do not prejudice escape from the gallery.
See para 2.15
NOTES:
1. This diagram does not apply where the gallery is provided with one of the following:
i. An alternative escape route
ii. An emergency escape window (where the gallery floor is not more than 4.5m above ground level).
2. Any cooking facilities within a room containing a gallery should comply with one of the following conditions:
i. Be enclosed with fire resisting construction
ii. Be remote from the stair to the gallery and positioned such that they do not prejudice escape from the gallery.
See para 3.13
A lift shaft serving storeys above ground level should not serve any basement, if either of the following applies.
a. There is only one escape stair serving storeys above ground level and smoke from a basement fire would adversely affect escape routes in the upper storeys.
b. The lift shaft is within the enclosure to an escape stair that terminates at ground level.
A person escaping through the common area, if confronted by the effects of a fire in another flat, should be able to turn away from it and make a safe escape via an alternative route.
Any external escape stair should meet all of the following conditions (Diagram 3.11).
a. Doors to the stair should be fire resisting (minimum E 30) and be fitted with a self-closing device, except for a single exit door from the building to the top landing of a downward-leading external stair, provided it is the only door onto the landing.
b. Fire resisting construction (minimum RE 30) is required for the building envelope within the following zones, measured from the flights and landings of the external stair.
i. 1800mm above and horizontally.
ii. 9m vertically below.
iii. 1100mm above the top landing of the stair (except where the stair leads from basement to ground level).
c. Fire resisting construction (minimum RE 30) should be provided for any part of the building (including doors) within 1800mm of the escape route from the foot of the stair to a place of safety. This does not apply if there are alternative escape routes from the foot of the external escape stair.
d. Glazing in areas of fire resisting construction should be fixed shut and fire resisting (in terms of integrity but not insulation) (minimum E 30).
e. Stairs more than 6m in height above ground level (e.g. where they are provided above a podium) should be protected from adverse weather. Protection should prevent the build-up of snow or ice but does not require full enclosure.
In buildings with more than three storeys above the ground storey, stairs may serve the flats and other occupancies if all of the following apply.
a. The flat is ancillary to the main use of the building.
b. The flat has an independent alternative escape route.
c. The stair is separated from occupancies on lower storeys by a protected lobby (minimum REI 30) at each of those storeys.
d. The stair enclosure has at least the same standard of fire resistance as the structural elements of the building (see Appendix B, Table B4); if the stair is a firefighting stair, it should comply with the provisions in Section 15 (see also paragraph 3.60).
e. Any automatic fire detection and alarm system fitted in the main part of the building also covers all flats.
f. Any security measures in any parts of the building do not prevent escape at all material times.
Single steps on escape routes should be prominently marked. A single step on the line of a doorway is acceptable, subject to paragraph 3.107.
Fire resistance test criteria are set out in Appendix C. Standards of performance are summarised in Table C1.
The door of any doorway or exit should be hung to open in the direction of escape whenever reasonably practicable. It should always be hung to open in the direction of escape if more than 60 people might be expected to use it during a fire.
All doors on escape routes should be hung to meet both of the following conditions.
a. Open by a minimum of 90 degrees.
b. Open with a swing that complies with both of the following.
i. Is clear of any change of floor level, other than a threshold or single step on the line of the doorway.
ii. Does not reduce the effective width of any escape route across a landing.
Lift wells should comply with one of the following conditions.
a. Be sited within the enclosures of a protected stairway.
b. Be enclosed with fire resisting construction (minimum REI 30) when in a position that might prejudice the means of escape.
In divided corridors (paragraph 3.25 and following) with cavities, fire-stopping should be provided to prevent alternative escape routes being affected by fire and/or smoke.
alternative exit
A gallery should comply with one of the following.
a. It should be provided with an alternative exit.
b. It should be provided with an emergency escape window, as described in paragraph 2.10, where the gallery floor is a maximum of 4.5m above ground level.
c. It should meet all the conditions shown in Diagram 2.6.
See para 2.6
Example of alternative exit in para 2.6(a) (see definition in Appendix A)
See Diagram 2.1c. The dwellinghouse should have either of the following. Cavity barriers or a fire resisting ceiling (minimum EI 30) should be provided above a protected stairway enclosure (Diagram 2.3). b. Alternative escape route – a top storey separated from lower storeys by fire resisting construction (minimum REI 30) and with an alternative escape route leading to its own final exit.
a. Protected stairway – a stair separated by fire resisting construction (minimum REI 30) at all storeys, that complies with one of the following.
i. Extends to a final exit (Diagram 2.2a).
ii. Gives access to a minimum of two ground level final exits that are separated from each other by fire resisting construction (minimum REI 30) and fire doorsets (minimum E 20) (Diagram 2.2b).
Final exits should not present a barrier for disabled people. Where the route to a final exit does not include stairs, a level threshold and, where necessary, a ramp should be provided.
Final exit locations should be clearly visible and recognisable.
For flats more than 4.5m above ground level, a balcony outside an alternative exit should be a common balcony meeting the conditions described in paragraph 3.22.
A gallery should comply with one of the following.
a. It should be provided with an alternative exit.
b. It should be provided with an emergency escape window, as described in paragraph 3.6, where the gallery floor is a maximum of 4.5m above ground level.
c. It should meet the conditions shown in Diagram 3.1.
One of the following approaches should be adopted, observing the inner room restrictions described in paragraphs 3.7 and 3.8.
a. Provide a protected entrance hall (minimum REI 30) serving all habitable rooms that meets the conditions shown in Diagram 3.2.
b. Plan the flat to meet the conditions shown in Diagram 3.3, so that both of the following apply.
i. The travel distance from the flat entrance door to any point in any habitable room is a maximum of 9m.
ii. Cooking facilities are remote from the main entrance door and do not impede the escape route from anywhere in the flat.
c. Provide an alternative exit from the flat complying with paragraph 3.19.
Where access from any habitable room to the entrance hall or flat entrance is impossible without passing through another room, all of the following conditions should be met (Diagram 3.4).
a. Bedrooms should be separated from living accommodation by fire resisting construction (minimum REI 30) and fire doorsets (minimum E 20).
b. The alternative exit should be in the part of the flat that contains the bedrooms.
When multi-storey flats do not have their own external entrance at ground level, adopt one of the following approaches.
a. Approach 1 – provide at least one alternative exit from each habitable room that is not on the entrance storey of the flat (Diagram 3.5 and paragraph 3.22).
b. Approach 2 – provide at least one alternative exit from each storey that is not the entrance storey of the flat. All habitable rooms should have direct access to a protected landing (Diagram 3.6 and paragraph 3.22).
Approach 3 – provide a protected stairway plus a sprinkler system in accordance with Appendix E (smoke alarms should also be provided in accordance with Section 1).
d. Approach 4 – if the vertical distance between the entrance storey of the flat and any of the storeys above or below does not exceed 7.5m, provide all of the following.
i. A protected stairway.
ii. Additional smoke alarms in all habitable rooms.
iii. A heat alarm in any kitchen.
Any alternative exit from a flat should comply with all of the following.
a. It should be remote from the main entrance door to the flat.
b. It should lead to a final exit, via a common stair if necessary, through one of the following.
i. A door to an access corridor, access lobby or common balcony.
ii. An internal private stair leading to an access corridor, access lobby or common balcony at another level.
iii. A door to a common stair.
iv. A door to an external stair.
v. A door to an escape route over a flat roof.
Any access route leading to a final exit or common stair should comply with the provisions for means of escape in the common parts of a flat (see paragraph 3.25).
See para 3.19
NOTE: The bedrooms are not classified as inner rooms because escape is possible in two directions.
Fire doorset
Fire resisting construction (minimum REI 30) between living and bedroom accommodation
Alternative exit
See para 3.21
NOTE: This only applies where at least one storey is more than 4.5m above ground level.
Alternative exit
Bathroom
ENTRANCE LEVEL
LEVEL(S) ABOVE OR BELOW ENTRANCE LEVEL
See para 3.21
NOTE: This only applies where at least one storey is more than 4.5m above ground level.
Fire doorset
Fire resisting stair enclosure(minimum REI 30)
Alternative exit
annex c: glossary
Fire resistance test criteria are set out in Appendix C. Standards of performance are summarised in Table C1.
appliance compartment
The wall of a flue, duct containing flues or appliance ventilation duct(s) should have a fire resistance (REI) that is at least half of any compartment wall or compartment floor it passes through or is built into (Diagram 9.5).
appliance ventilation duct
Openings should be limited to those for any of the following.
a. Fire doorsets of the appropriate fire resistance, fitted in accordance with the provisions in Appendix C.
b. Pipes, ventilation ducts, service cables, chimneys, appliance ventilation ducts or ducts encasing one or more flue pipes, complying with the provisions in Section 9.
c. Refuse chutes of class A1 construction.
d. Atria designed in accordance with Annexes B and C of BS 9999.
e. Protected shafts that conform to the provisions in the following paragraphs.
The wall of a flue, duct containing flues or appliance ventilation duct(s) should have a fire resistance (REI) that is at least half of any compartment wall or compartment floor it passes through or is built into (Diagram 9.5).
approved document
In sheltered housing, the guidance in Approved Document B Volume 2 should be consulted for the design of communal facilities, such as a common lounge.
This approved document includes reference to selected guidance for buildings other than dwellings. For the design of mixed use buildings, Approved Document B Volume 2 should be consulted in addition to the guidance contained in this approved document.
This approved document includes reference to selected guidance for buildings other than dwellings. For the design of mixed use buildings, Approved Document B Volume 2 should be consulted in addition to the guidance contained in this approved document.
The fire safety requirements of the Building Regulations will probably be satisfied by following the relevant guidance in this approved document. However, approved documents provide guidance for some common building situations, and there may be alternative methods of complying with the Building Regulation requirements. If alternative methods are adopted, the overall level of safety should not be lower than the approved document provides. It is the responsibility of those undertaking the work to demonstrate compliance. If other standards or guidance documents are adopted, the relevant fire safety recommendations in those publications should be followed in their entirety. However, in some circumstances it may be necessary to use one publication to supplement another. Care must be taken when using supplementary guidance to ensure that an integrated approach is used in any one building. Guidance documents intended specifically for assessing fire safety in existing buildings often include less onerous provisions than those for new buildings and are therefore unlikely to be appropriate for building work that is controlled by the Building Regulations. Buildings for industrial and commercial activities that present a special fire hazard, e.g. those that sell fuels, may require additional fire precautions to those in this approved document.
The fire safety requirements of the Building Regulations will probably be satisfied by following the relevant guidance in this approved document. However, approved documents provide guidance for some common building situations, and there may be alternative methods of complying with the Building Regulation requirements. If alternative methods are adopted, the overall level of safety should not be lower than the approved document provides. It is the responsibility of those undertaking the work to demonstrate compliance. If other standards or guidance documents are adopted, the relevant fire safety recommendations in those publications should be followed in their entirety. However, in some circumstances it may be necessary to use one publication to supplement another. Care must be taken when using supplementary guidance to ensure that an integrated approach is used in any one building. Guidance documents intended specifically for assessing fire safety in existing buildings often include less onerous provisions than those for new buildings and are therefore unlikely to be appropriate for building work that is controlled by the Building Regulations. Buildings for industrial and commercial activities that present a special fire hazard, e.g. those that sell fuels, may require additional fire precautions to those in this approved document.
A ramp forming part of an escape route should meet the provisions in Approved Document M. Any sloping floor or tier should have a pitch of not more than 35 degrees to the horizontal.
Further guidance on the construction of firefighting stairs is given in Section 15 (see also paragraph 3.60). Dimensional constraints on the design of stairs are given in Approved Document K.
Further guidance on the construction of firefighting stairs is given in Section 15 (see also paragraph 3.60). Dimensional constraints on the design of stairs are given in Approved Document K.
Glazed elements should also comply with the following, where necessary.
a. If the enclosure forms part of a protected shaft: Section 7.
b. Appendix B, Table B5.
c. Guidance on the safety of glazing: Approved Document K.
Glazed elements should also comply with the following, where necessary.
a. If the enclosure forms part of a protected shaft: Section 7.
b. Appendix B, Table B5.
c. Guidance on the safety of glazing: Approved Document K.
Doors should contain vision panels in both of the following situations.
a. Where doors on escape routes divide corridors.
b. Where doors are hung to swing both ways.
Approved Document M contains guidance about vision panels in doors across accessible corridors and Approved Document K contains guidance about the safety of glazing.
Doors should contain vision panels in both of the following situations.
a. Where doors on escape routes divide corridors.
b. Where doors are hung to swing both ways.
Approved Document M contains guidance about vision panels in doors across accessible corridors and Approved Document K contains guidance about the safety of glazing.
assessment in lieu of test
Where it is proposed to assess the classification of a product or system in lieu of carrying out a specific test (as in paragraph B1c), this should be done in accordance with the relevant standard for extended application for the test in question and should include details of the test evidence that has been used to support the assessment.
For performance classifications where there is no specific standard for extended
application, assessment reports should be produced in accordance with the principles of BS EN 15725 and should include details of the test evidence that has been used to support the assessment. Further information on best practice is provided in the Passive Fire Protection Forum’s Guide to Undertaking Technical Assessments of the Fire Performance of Construction Products Based on Fire Test Evidence.
NOTE: Regulation 7(2) limits components used in or on the external walls of certain buildings to materials achieving class A2-s1, d0 or class A1 (see Section 12).
Assessments cannot be used to demonstrate compliance with this requirement.
associate
The Building Regulations are intended to ensure a reasonable standard of life safety in a fire. The protection of property, including the building itself, often requires additional measures. Insurers usually set higher standards before accepting the insurance risk. Many insurers use the RISC Authority Design Guide for the Fire Protection of Buildings by the Fire Protection Association (FPA) as a basis for providing guidance to the building designer on what they require. Further information on the protection of property can be obtained from the FPA website: www.thefpa.co.uk.
Smoke and heat alarms should have a standby power supply, such as a battery (rechargeable
or non-rechargeable) or capacitor. More information on power supplies is given in clause 15 of
BS 5839-6.
NOTE: The term ‘fire alarm system’ describes the combination of components for giving an audible
and/or other perceptible warning of fire.
NOTE: In this document, the term ‘fire detection system’ describes any type of automatic sensor
network and associated control and indicating equipment. Sensors may be sensitive to smoke,
heat, gaseous combustion products or radiation. Automatic sprinkler systems can also be used to
operate a fire alarm system.
The box should meet all of the following conditions.
a. Sized to accommodate all necessary information.
b. Easily located and identified by firefighters.
c. Secured to resist unauthorised access but readily accessible by firefighters.
d. Protected from the weather.
15.21 Best practice guidance can be found in Sections 2 to 4 of the Code of Practice for the Provision of Premises Information Boxes in Residential Buildings published by the Fire Industry Association (FIA).
Best practice guidance can be found in Sections 2 to 4 of the Code of Practice for the Provision of Premises Information Boxes in Residential Buildings published by the Fire Industry Association (FIA).
Firefighting stairs and firefighting lifts should be approached from either of the following.
a. A firefighting lobby.
b. A protected corridor or protected lobby that complies with the following guidance.
i. Means of escape (Section 3).
ii. Compartmentation (Section 7).
Both the stair and lobby of the firefighting shaft should be provided with a means of venting smoke and heat (see clause 27.1 of BS 9999).
Only services associated with the firefighting shaft, such as ventilation systems and lighting for the firefighting shafts, should pass through or be contained within the firefighting shaft.
Doors of a firefighting lift landing should be a maximum of 7.5m from the door to the firefighting stair (Diagram 15.1).
Divide a common corridor connecting two or more storey exits with a fire doorset fitted with a self-closing device (minimum E 30 Sa). See Diagram 3.8. Associated screens should be fire resisting. Site doors so that smoke does not affect access to more than one stair.
Guidance on the design, installation and maintenance of measures to contain fires or slow their spread is given in Ensuring Best Practice for Passive Fire Protection in Buildings produced by the Association for Specialist Fire Protection (ASFP).
Recommendations for the specification, design, construction, installation and maintenance of fire
doorsets constructed with non-metallic door leaves are given in BS 8214.
Guidance on timber fire resisting doorsets, in relation to the new European test standard, may be
found in Timber Fire Resisting Doorsets: Maintaining Performance Under the New European Test
Standard published by the Timber Research and Development Association (TRADA).
Guidance for metal doors is given in Code of Practice for Fire Resisting Metal Doorsets published by
the Door and Shutter Manufacturers’ Association (DSMA).
automatic control
Smoke and heat alarms should have a standby power supply, such as a battery (rechargeable
or non-rechargeable) or capacitor. More information on power supplies is given in clause 15 of
BS 5839-6.
NOTE: The term ‘fire alarm system’ describes the combination of components for giving an audible
and/or other perceptible warning of fire.
NOTE: In this document, the term ‘fire detection system’ describes any type of automatic sensor
network and associated control and indicating equipment. Sensors may be sensitive to smoke,
heat, gaseous combustion products or radiation. Automatic sprinkler systems can also be used to
operate a fire alarm system.
In a system that recirculates air, smoke detectors should be fitted in the extract ductwork before both of the following.
a. The point where recirculated air is separated from air to be discharged to the outside.
b. Any filters or other air cleaning equipment.
When smoke is detected, detectors should do one of the following.
i. Cause the system to immediately shut down.
ii. Switch the ventilation system from recirculating mode to extraction to divert smoke to outside the building.
Rolling shutters should be capable of manual opening and closing for firefighting purposes (see Section 15). Rolling shutters across a means of escape should only be released by a heat sensor, such as a fusible link or electric heat detector, in the immediate vicinity of the door. Unless a shutter is also intended to partially descend as part of a boundary to a smoke reservoir, shutters across a means of escape should not be closed by smoke detectors or a fire alarm system.
automatic release mechanism
Electrically powered locks should return to the unlocked position in all of the following situations.
a. If the fire detection and alarm system operates.
b. If there is loss of power or system error.
c. If the security mechanism override is activated.
Security mechanism overrides for electrically powered locks should be a Type A call point, as described in BS 7273-4. The call point should be positioned on the side approached by people escaping. If the door provides escape in either direction, a call point should be installed on both sides of the door.
Guidance on door closing and ‘hold open’ devices for fire doorsets is set out in Appendix C.
Where revolving doors, automatic doors and turnstiles are placed across escape routes they should comply with one of the following.
a. They are automatic doors of the required width and comply with one of the following conditions.
i. Their failsafe system provides outward opening from any open position.
ii. They have a monitored failsafe system to open the doors if the mains electricity supply fails.
iii. They failsafe to the open position if the power fails.
b. Non-automatic swing doors of the required width are provided immediately adjacent to the revolving or automatic door or turnstile.
Where ducts pass between fire-separating elements to serve multiple flats or dwellings, fire dampers or fire and smoke dampers should be actuated by both of the following.
a. Smoke detector-controlled automatic release mechanisms.
b. Thermally actuated devices.
Smoke detectors should be sited so as to prevent the spread of smoke as early as practicable by activating the fire and smoke dampers. Smoke detectors and automatic release mechanisms used to activate fire dampers and/or fire and smoke dampers should conform to BS EN 54-7 and BS 5839-3 respectively.
Further information on fire dampers and/or fire and smoke dampers is given in the ASFP Grey Book.
Except for doorsets listed in paragraph C12, all fire doorsets should be marked with one of the
following fire safety signs, complying with BS 5499-5, as appropriate.
a. To be kept closed when not in use – mark ‘Fire door keep shut’.
b. To be kept locked when not in use – mark ‘Fire door keep locked shut’.
c. Held open by an automatic release mechanism or free swing device – mark ‘Automatic fire door
keep clear’.
All fire doorsets should be marked on both sides, except fire doorsets to cupboards and service
ducts, which should be marked on the outside.
If a self-closing device would be considered to interfere with the normal approved use of the
building, self-closing fire doors may be held open by one of the following.
a. A fusible link, but not if the doorset is in an opening provided as a means of escape unless it
complies with paragraph C7.
b. An automatic release mechanism activated by an automatic fire detection and alarm system.
c. A door closer delay device.
availability
Where a storey or part of a building has multiple escape routes available, one may be over a flat roof that complies with all of the following.
a. It should be part of the same building from which escape is being made.
b. The route across the roof should lead to a storey exit or external escape route.
c. The part of the roof (including its supporting structure) forming the escape route, and any opening within 3m of the escape route, should be of fire resisting construction (minimum REI 30).
d. The route should be clearly defined and guarded by walls and/or protective barriers to protect against falling.
Where a storey or part of a building has multiple escape routes available, one may be over a flat roof that complies with all of the following.
d. The route should be clearly defined and guarded by walls and/or protective barriers to protect against falling.
Guidance on the design of smoke control systems that use pressure differentials is available in BS EN 12101-6.
Where more than one escape route is available from a storey (or part of a building), then some of the escape routes from that storey or part of the building may be by way of an external stair provided all of the following conditions are met:
a. There is a at least one internal escape stair from every part of each storey (excluding plant areas).
b. The stair serves a floor not more than 6m above either the ground level or a roof podium which is itself served by an independent protected stairway.
c. The stair meets the provisions in paragraph 3.68.
Proprietary, tested fire-stopping and sealing systems are available and may be used. Different materials suit different situations and not all are suitable in every situation.
Where required, sprinkler systems should be provided throughout the building or separated part,
unless acting as a compensatory feature to address a specific risk. They should be designed and
installed in accordance with the following.
a. For residential buildings, the requirements of BS 9251.
b. For non-residential buildings, or residential buildings outside the scope of BS 9251, the
requirements of BS EN 12845, including the relevant hazard classification together with
additional measures to improve system reliability and availability as described in Annex F of the
standard.
NOTE: Any sprinkler system installed to satisfy the requirements of Part B of the Building
Regulations should be provided with additional measures to improve system reliability and
availability and is therefore to be regarded as a life safety system. However, there may be some
circumstances in which additional measures to improve system reliability and availability specified
in Annex F of BS EN 12845 are inappropriate or unnecessary.
b2 internal fire spread linings
Internal fire spread (linings)
B2.(1) To inhibit the spread of fire within the building, the internal linings shall —
(a) adequately resist the spread of flame over their surfaces; and
(b) have, if ignited, either a rate of heat release or a rate of fire growth, which is reasonable in the circumstances.
(2) In this paragraph “internal linings” means the materials or products used in lining any partition, wall, ceiling or other internal structure.
In the Secretary of State’s view, requirement B2 is met by achieving a restricted spread of flame
over internal linings. The building fabric should make a limited contribution to fire growth,
including a low rate of heat release.
It is particularly important in circulation spaces, where linings may offer the main means by which
fire spreads and where rapid spread is most likely to prevent occupants from escaping.
Requirement B2 does not include guidance on the following.
a. Generation of smoke and fumes.
b. The upper surfaces of floors and stairs.
c. Furniture and fittings.
The external wall of a building should not provide a medium for fire spread if that is likely to be a risk to health and safety. Combustible materials and cavities in external walls and attachments to them can present such a risk, particularly in tall buildings. The guidance in this section is designed to reduce the risk of fire spread as well as the risk of ignition from flames coming from adjacent buildings.
NOTE: Projections from the building line, such as a canopy or a loading platform, can be ignored when assessing separation distance. This does not apply where the canopy is enclosed by side walls.
Distance to relevant boundary measured from building line
See para 11.12
Provisions for the fire properties of roofs are given in other parts of this document.
a. Requirement B1 – for roofs that are part of a means of escape.
b. Requirement B2 – for the internal surfaces of rooflights as part of internal linings.
c. Requirement B3 – for roofs that are used as a floor and for roofs passing over a compartment wall.
d. Section 11 – the circumstances in which a roof is subject to the provisions for space separation.
The highest National product performance classification for lining materials is Class O. This is achieved if a material or the surface of a composite product is either:
a. composed throughout of materials of limited combustibility; or
b. a Class 1 material which has a fire propagation index (I) of not more than 12 and sub-index (i1) of not more than 6.
Note: Class O is not a classification identified in any British Standard test.
The highest national product performance classification for lining materials is Class 0. This is achieved if a material or the surface of a composite product is either:
a. composed throughout of materials of limited combustibility; or
b. a Class 1 material which has a fire propagation index (I) of not more than 12 and sub-index (i1) of not more than 6.
Note: Class O is not a classification identified in any British Standard test.
Single steps on escape routes should be prominently marked. A single step on the line of a doorway is acceptable, subject to paragraph 3.107.
The surface linings of walls and ceilings should meet the classifications in Table 4.1.
Parts of walls in rooms may be of lower performance than stated in Table 4.1, but no worse than class D-s3, d2. In any one room, the total area of lower performance wall lining should be less than an area equivalent to half of the room’s floor area, up to a maximum of 20m2 of wall lining.
To reduce the risk of fire spreading over the roof from one compartment to another, a 1500mm wide zone of the roof, either side of the wall, should have a covering classified as BROOF(t4), on a substrate or deck of a material rated class A2-s3, d2 or better, as set out in Diagram 5.2a.
Thermoplastic rooflights that, because of paragraph 12.7, are regarded as having a BROOF(t4) classification are not suitable for use in that zone.
It is not appropriate to complete a line of compartment walls by fitting cavity barriers above them. The compartment wall should be extended to the underside of the floor or roof above.
Where services could provide a source of ignition, the risk of fire developing and spreading into adjacent compartments should be controlled.
It is not appropriate to complete a line of compartment walls by fitting cavity barriers above them. The compartment walls should extend to the underside of the floor or roof above.
Every joint, imperfect fit and opening for services through a fire-separating element should be sealed with fire-stopping to ensure that the fire resistance of the element is not impaired. Fire-stopping delays the spread of fire and, generally, the spread of smoke as well.
Performance of the resistance of roofs to external fire exposure is measured in terms of penetration through the roof construction and the spread of flame over its surface.
b3 internal fire spread structure
B3.(1) The building shall be designed and constructed so that, in the event of fire, its stability will be maintained for a reasonable period
(2) A wall common to two or more buildings shall be designed and constructed so that it adequately resists the spread of fire between those buildings.
For the purposes of this sub-paragraph a house in a terrace and a semi-detached house are each to be treated as a separate building.
(3) Where reasonably necessary to inhibit the spread of fire within the building, measures shall be taken, to an extent appropriate to the size and intended use of the building, comprising either or both of the following—
(a) sub-division of the building with fire-resisting construction;
(b) installation of suitable automatic fire suppression systems.
(4) The building shall be designed and constructed so that the unseen spread of fire and smoke within concealed spaces in its structure and fabric is inhibited.
Requirement B3(3) does not apply to material alterations to any prison provided under section 33 of the Prison Act 1952.
b4 external fire spread
The external envelope of a building should not contribute to undue fire spread from one part of a
building to another part. This intention can be met by constructing external walls so that both of
the following are satisfied.
a. The risk of ignition by an external source to the outside surface of the building and spread of
fire over the outside surface is restricted.
b. The materials used to construct external walls, and attachments to them, and how they are
assembled do not contribute to the rate of fire spread up the outside of the building.
The extent to which this is necessary depends on the height and use of the building.
The external envelope of a building should not provide a medium for undue fire spread to
adjacent buildings or be readily ignited by fires in adjacent buildings. This intention can be met by
constructing external walls so that all of the following are satisfied.
a. The risk of ignition by an external source to the outside surface of the building is restricted.
b. The amount of thermal radiation that falls on a neighbouring building from window openings
and other unprotected areas in the building on fire is not enough to start a fire in the other
building.
c. Flame spread over the roof and/or fire penetration from external sources through the roof is
restricted.
The extent to which this is necessary depends on the use of the building and its position in relation
to adjacent buildings and therefore the site boundary.
The external wall of a building should not provide a medium for fire spread if that is likely to be a risk to health and safety. Combustible materials and cavities in external walls and attachments to them can present such a risk, particularly in tall buildings. The guidance in this section is designed to reduce the risk of fire spread as well as the risk of ignition from flames coming from adjacent buildings.
This section provides guidance on resisting fire spread over external walls; however, it does not deal with fire resistance of external walls. An external wall may need fire resistance to meet the provisions of Section 3 (Means of escape – flats), Section 6 (Loadbearing elements of structure – flats), Section 11 (Resisting fire spread from one building to another) or Section 15 (Access to buildings for firefighting personnel – flats).
The external envelope of a building should not provide a medium for fire spread if it is likely to be a risk to health or safety. The use of combustible materials for cladding framework, or of combustible thermal insulation as an overcladding or in ventilated cavities, may present such a risk in tall buildings, even though the provisions for external surfaces in Diagram 40 may have been satisfied.
In a building with a storey 18m or more above ground level, insulation material used in ventilated cavities in the external wall construction should be of limited combustibility (see Appendix A). This restriction does not apply to masonry cavity wall construction which complies with Diagram 32 in Section 10. Advice on the use of thermal insulation material is given in the BRE Report Fire performance of external thermal insulation for walls of multi-storey buildings (BR 135, 1988).
People should be able to rapidly leave the area around the building. Direct access to a street, passageway, walkway or open space should be available. The route away from the building should comply with the following.
a. Be well defined.
b. If necessary, have suitable guarding.
Performance of the resistance of roofs to external fire exposure is measured in terms of penetration through the roof construction and the spread of flame over its surface.
b5 access and facilities for the fire service
Access and facilities for the fire service
B5.(1)The building shall be designed and constructed so as to provide reasonable facilities to assist fire fighters in the protection of life.
(2)Reasonable provision shall be made within the site of the building to enable fire appliances to gain access to the building.
Provisions covering access and facilities for the fire service are to safeguard the health and safety of
people in and around the building. Their extent depends on the size and use of the building. Most
firefighting is carried out within the building. In the Secretary of State’s view, requirement B5 is met
by achieving all of the following.
a. External access enabling fire appliances to be used near the building.
b. Access into and within the building for firefighting personnel to both:
i. search for and rescue people
ii. fight fire.
c. Provision for internal fire facilities for firefighters to complete their tasks.
d. Ventilation of heat and smoke from a fire in a basement.
If an alternative approach is taken to providing the means of escape, outside the scope of this
approved document, additional provisions for firefighting access may be required. Where deviating
from the general guidance, it is advisable to seek advice from the fire and rescue service as early as
possible (even if there is no statutory duty to consult).
e. A facility to store building information for firefighters to complete their tasks.
barrier
Cavity barriers should be provided in accordance with Section 5 in dwellinghouses and Section 8 in flats.
If windows are replaced, it may be necessary to provide cavity barriers around the opening in accordance with Section 5.
See para 2.5
Alternative cavity barrier arrangements in roof space over protected stairway in a house with a storey more than 4.5m above ground level
To reduce the potential for fire spread, cavity barriers should be provided for both of the following.
a. To divide cavities.
b. To close the edges of cavities.
Cavity barriers should not be confused with fire-stopping details (Section 9).
Cavity barriers should be provided at all of the following locations.
a. At the edges of cavities, including around openings (such as windows, doors and exit/entry points for services).
b. At the junction between an external cavity wall and every compartment floor and compartment wall.
c. At the junction between an internal cavity wall and every compartment floor, compartment wall or other wall or door assembly forming a fire resisting barrier.
This does not apply where a wall meets the conditions of Diagram 5.3.
It is not appropriate to complete a line of compartment walls by fitting cavity barriers above them. The compartment wall should be extended to the underside of the floor or roof above.
Cavity barriers, tested from each side separately, should provide a minimum of both of the following:
a. 30 minutes’ integrity (E 30)
b. 15 minutes’ insulation (I 15).
They may be formed by a construction provided for another purpose if it achieves the same performance.
Cavity barriers in a stud wall or partition, or provided around openings, may be formed of any of the following.
a. Steel, a minimum of 0.5mm thick.
b. Timber, a minimum of 38mm thick.
c. Polythene-sleeved mineral wool, or mineral wool slab, under compression when installed in the cavity.
d. Calcium silicate, cement-based or gypsum-based boards, a minimum of 12mm thick.
These do not necessarily achieve the performance specified in paragraph 5.20.
NOTE: Cavity barriers provided around openings may be formed by the window or door frame, if the frame is constructed of steel or timber of the minimum thickness in (a) or (b), as appropriate.
Cavity barriers should be tightly fitted to a rigid construction and mechanically fixed in position. If this is not possible (e.g. where a cavity barrier joins to slates, tiles, corrugated sheeting or similar materials) the junction should be fire-stopped.
Cavity barriers should be fixed so their performance is unlikely to be made ineffective by any of the following.
a. Movement of the building due to subsidence, shrinkage or temperature change, and movement of the external envelope due to wind.
b. During a fire, collapse of services penetrating the cavity barriers, either by the failure of the supporting system or through degradation of the service itself (e.g. by melting or burning).
c. During a fire, failure of the cavity barrier fixings. (In roof spaces, where cavity barriers are fixed to roof members, there is no expectation of fire resistance from roof members provided for the purpose of support.)
d. During a fire, failure of any material or construction to which cavity barriers abut. (For example, a suspended ceiling that continues over a fire resisting wall or partition collapses, and the cavity barrier fails prematurely because the ceiling was not designed to provide a minimum fire resistance of EI 30.)
Openings should be limited to the following.
a. Fire doorsets with a minimum E 30 rating, fitted in accordance with Appendix C.
b. The passage of pipes that follow the provisions in Section 9.
c. The passage of cables or conduits containing one or more cables.
d. Openings fitted with a suitably mounted and appropriate fire damper.
e. Ducts that are either of the following.
i. Fire resisting (minimum E 30).
ii. Fitted with a suitably mounted and appropriate fire damper where they pass through the cavity barrier.
NOTE: For further guidance on openings in cavity barriers see Section 9.
Fire-stopping (same resistance as compartment)
Cavity barriers
NOTE:
1. See paragraph 8.5
See para 8.2
To reduce the potential for fire spread, cavity barriers should be provided for both of the following.
a. To divide cavities.
b. To close the edges of cavities.
See Diagram 8.1. Cavity barriers should not be confused with fire-stopping details (Section 9).
Cavity barriers should be provided at all of the following locations.
a. At the edges of cavities, including around openings (such as windows, doors and exit/entry points for services).
b. At the junction between an external cavity wall and every compartment floor and compartment wall.
c. At the junction between an internal cavity wall and every compartment floor, compartment wall or other wall or door assembly forming a fire resisting barrier.
This does not apply where a wall meets the conditions of Diagram 8.2.
It is not appropriate to complete a line of compartment walls by fitting cavity barriers above them. The compartment walls should extend to the underside of the floor or roof above.
Cavity barriers are not required between double-skinned corrugated or profiled insulated roof sheeting, if the sheeting complies with all of the following.
a. The sheeting is rated class A2-s3, d2 or better.
b. Both surfaces of the insulating layer are rated class C-s3, d2 or better.
c. Both surfaces of the insulating layer make contact with the inner and outer skins of cladding (Diagram 8.4).
Cavity barriers, tested from each side separately, should provide a minimum of both of the following:
a. 30 minutes’ integrity (E 30)
b. 15 minutes’ insulation (I 15).
They may be formed by a construction provided for another purpose if it achieves the same performance.
Cavity barriers should meet the requirements set out in paragraphs 5.21 to 5.24.
Provide a proprietary, tested sealing system that will maintain the fire resistance of the wall, floor or cavity barrier.
basement
NOTES:
For single storey buildings, the periods under the heading ‘Up to 5’ apply. If single storey buildings have basements, for the basement storeys the period appropriate to their depth applies.
* For the floor over a basement or, if there is more than one basement, the floor over the topmost basement, the higher of the period for the basement storey and the period for the ground or upper storey applies.
† For compartment walls that separate buildings, the period is increased to a minimum of 60 minutes.
+ For any floor that does not contribute to the support of the building within a flat of more than one storey, the period is reduced to 30 minutes.
§ For flat conversions, refer to paragraphs 6.5 to 6.7 regarding the acceptability of 30 minutes.
‡ For elements that do not form part of the structural frame, the period is reduced to 90 minutes.
# For elements that protect the means of escape, the period is increased to 30 minutes.
1. Refer to note 1, Table B3 for the specific provisions of test.
2. Blocks of flats with a floor more than 30m above ground level should be fitted with a sprinkler system in accordance with Appendix E.
NOTE:
Sprinklers only need to be provided within the individual flats, they are not required in the common areas such as stairs, corridors or landings when these areas are fire sterile.
3.‘With sprinkler system’ means that the building is fitted throughout with an automatic sprinkler system in accordance with Appendix E.
4. Very large (over 18m in height or with a 10m deep basement) or unusual dwellinghouses are outside the scope of the guidance provided with regard to dwellinghouses.
5. A minimum of 30 minutes in the case of three storey dwellinghouses, increased to 60 minutes minimum for compartment walls separating buildings.
6. Buildings within the ‘office’, ‘shop and commercial’, ‘assembly and recreation’, ‘industrial’ and ‘storage and other non-residential’ (except car parks for light vehicles) purpose groups (purpose groups 3 to 7(a)) require sprinklers where there is a top storey above 30m.
The sprinkler system should be provided in accordance with Appendix E.
7. The car park should comply with the relevant provisions in the guidance on requirement B3, Section 11 of
Approved Document B Volume 2.
8. For the purposes of meeting the Building Regulations, the following types of steel elements are deemed to have satisfied the minimum period of fire resistance of 15 minutes when tested to the European test method.
i. Beams supporting concrete floors, maximum Hp/A=230m-1 operating under full design load.
ii. Free-standing columns, maximum Hp/A=180m-1 operating under full design load.
iii. Wind bracing and struts, maximum Hp/A=210m-1 operating under full design load.
Guidance is also available in BS EN 1993-1-2.
A large dwellinghouse of two storeys (excluding basement storeys) should be fitted with a Grade A
Category LD3 fire detection and alarm system, as described in BS 5839-6.
A large dwellinghouse of three or more storeys (excluding basement storeys) should be fitted with
a Grade A Category LD2 fire detection and alarm system as described in BS 5839-6.
In low rise buildings without deep basements, access for firefighting personnel is typically achieved by providing measures for fire service vehicle access in Section 13 and means of escape.
A building with basement storeys should have firefighting shafts in accordance with the following.
a. There is a basement more than 10m below the fire and rescue service vehicle access level. The firefighting shafts should contain firefighting lifts.
b. There are two or more basement storeys, each with a minimum area of 900m2. The firefighting shafts do not need to include firefighting lifts.
The building’s height and size determine whether firefighting shafts also serve upper storeys.
Heat and smoke from basement fires vented via stairs can inhibit access for firefighting personnel. This may be reduced by providing smoke outlets, or smoke vents, which allow heat and smoke to escape from the basement levels to the open air. They can also be used by the fire and rescue service to let cooler air into the basements (Diagram 16.1).
Basement outlet with break-out or openable cover
Stallboard outlet with grille or removable cover
See para 16.1
If basement storeys are fitted with a sprinkler system in accordance with Appendix E, a mechanical smoke extraction system may be provided as an alternative to natural venting. Sprinklers do not need to be installed on the other storeys unless needed for other reasons.
Car parks are not normally expected to be fitted with sprinklers (see Section 11 of Approved Document B Volume 2).
Natural smoke outlet shafts should be separated from each other using construction of class A1 rating and fire resistance at least equal to that of the storeys they serve, where the shafts are either of the following.
a. From different compartments of the same basement storey.
b. From different basement storeys.
Each basement space should have one or more smoke outlets.
Where this is not practicable (for example, the plan area is deep and the amount of external wall is restricted by adjoining buildings), the perimeter basement spaces may be vented, with other spaces vented indirectly by opening connecting doors. This does not apply for places of special fire hazard (see paragraph 16.7).
If a basement is compartmented, each compartment should have one or more smoke outlets, rather than indirect venting.
A basement storey or compartment containing rooms with doors or windows does not need smoke outlets.
Smoke outlets connecting directly to the open air should be provided from every basement storey, except for any basement storey that has both of the following.
a. A maximum floor area of 200m2.
b. A floor a maximum of 3m below the adjacent ground level.
Basement storeys containing habitable rooms should have one of the following.
a. An emergency escape window or external door providing escape from the basement (paragraph 2.10).
b. A protected stairway (paragraph 2.5a) leading from the basement to a final exit.
If a building does not meet the criteria of paragraph 3.28, an escape stair forming part of the only escape route from an upper storey should not continue down to serve a basement storey. The basement storey should be served by a separate escape stair.
Basement storeys containing habitable rooms should have one of the following.
a. An emergency escape window or external door providing escape from the basement (see paragraph 3.6).
b. A protected stairway (minimum REI 30) leading from the basement to a final exit.
For the purposes of this paragraph, the ground storey of a building that has one or more basement storeys and no upper storeys may be considered as a single storey building. The fire resistance of the basement storeys should be that specified for basements.
basement level 01
Where multiple escape stairs serve the upper storeys, only one needs to end at ground level. Other stairs may connect with the basement storeys if there is a protected lobby or a protected corridor between the stairs and accommodation at each basement level.
basement level 02
Where multiple escape stairs serve the upper storeys, only one needs to end at ground level. Other stairs may connect with the basement storeys if there is a protected lobby or a protected corridor between the stairs and accommodation at each basement level.
basement storey
NOTES:
For single storey buildings, the periods under the heading ‘Up to 5’ apply. If single storey buildings have basements, for the basement storeys the period appropriate to their depth applies.
* For the floor over a basement or, if there is more than one basement, the floor over the topmost basement, the higher of the period for the basement storey and the period for the ground or upper storey applies.
† For compartment walls that separate buildings, the period is increased to a minimum of 60 minutes.
+ For any floor that does not contribute to the support of the building within a flat of more than one storey, the period is reduced to 30 minutes.
§ For flat conversions, refer to paragraphs 6.5 to 6.7 regarding the acceptability of 30 minutes.
‡ For elements that do not form part of the structural frame, the period is reduced to 90 minutes.
# For elements that protect the means of escape, the period is increased to 30 minutes.
1. Refer to note 1, Table B3 for the specific provisions of test.
2. Blocks of flats with a floor more than 30m above ground level should be fitted with a sprinkler system in accordance with Appendix E.
NOTE:
Sprinklers only need to be provided within the individual flats, they are not required in the common areas such as stairs, corridors or landings when these areas are fire sterile.
3.‘With sprinkler system’ means that the building is fitted throughout with an automatic sprinkler system in accordance with Appendix E.
4. Very large (over 18m in height or with a 10m deep basement) or unusual dwellinghouses are outside the scope of the guidance provided with regard to dwellinghouses.
5. A minimum of 30 minutes in the case of three storey dwellinghouses, increased to 60 minutes minimum for compartment walls separating buildings.
6. Buildings within the ‘office’, ‘shop and commercial’, ‘assembly and recreation’, ‘industrial’ and ‘storage and other non-residential’ (except car parks for light vehicles) purpose groups (purpose groups 3 to 7(a)) require sprinklers where there is a top storey above 30m.
The sprinkler system should be provided in accordance with Appendix E.
7. The car park should comply with the relevant provisions in the guidance on requirement B3, Section 11 of
Approved Document B Volume 2.
8. For the purposes of meeting the Building Regulations, the following types of steel elements are deemed to have satisfied the minimum period of fire resistance of 15 minutes when tested to the European test method.
i. Beams supporting concrete floors, maximum Hp/A=230m-1 operating under full design load.
ii. Free-standing columns, maximum Hp/A=180m-1 operating under full design load.
iii. Wind bracing and struts, maximum Hp/A=210m-1 operating under full design load.
Guidance is also available in BS EN 1993-1-2.
A large dwellinghouse of two storeys (excluding basement storeys) should be fitted with a Grade A
Category LD3 fire detection and alarm system, as described in BS 5839-6.
A large dwellinghouse of three or more storeys (excluding basement storeys) should be fitted with
a Grade A Category LD2 fire detection and alarm system as described in BS 5839-6.
Buildings in which firefighting shafts should be provided,
showing which storeys need to be served >18m >10m
a. Any building The upper storeys in any building with a storey more than 18m above fire service vehicle access level
b. Any building The basement storeys in any building with a basement more than 10m below fire service vehicle access level
c. Any building The basement storey(s) in any building with two or more basements each exceeding 900m2
Fire service vehicle access level
Two or more basement storeys each exceeding 900m2
Extent of firefighting Extent of firefighting lift stair
NOTES:
1.Height excludes any top storey(s) consisting exclusively of plant rooms.
2.Firefighting shafts should serve all floors through which they pass.
See para 15.2
A building with basement storeys should have firefighting shafts in accordance with the following.
a. There is a basement more than 10m below the fire and rescue service vehicle access level. The firefighting shafts should contain firefighting lifts.
b. There are two or more basement storeys, each with a minimum area of 900m2. The firefighting shafts do not need to include firefighting lifts.
The building’s height and size determine whether firefighting shafts also serve upper storeys.
In buildings where a firefighting shaft is required, a minimum of two firefighting shafts should be provided in either of the following situations.
a. A building that has both of the following.
i. A storey with a floor area of 900m2 or more.
ii. A storey 18m or more above the fire and rescue service vehicle access level.
b. A building with a basement storey which is more than 900m2.
If basement storeys are fitted with a sprinkler system in accordance with Appendix E, a mechanical smoke extraction system may be provided as an alternative to natural venting. Sprinklers do not need to be installed on the other storeys unless needed for other reasons.
Car parks are not normally expected to be fitted with sprinklers (see Section 11 of Approved Document B Volume 2).
Natural smoke outlet shafts should be separated from each other using construction of class A1 rating and fire resistance at least equal to that of the storeys they serve, where the shafts are either of the following.
a. From different compartments of the same basement storey.
b. From different basement storeys.
Each basement space should have one or more smoke outlets.
Where this is not practicable (for example, the plan area is deep and the amount of external wall is restricted by adjoining buildings), the perimeter basement spaces may be vented, with other spaces vented indirectly by opening connecting doors. This does not apply for places of special fire hazard (see paragraph 16.7).
If a basement is compartmented, each compartment should have one or more smoke outlets, rather than indirect venting.
A basement storey or compartment containing rooms with doors or windows does not need smoke outlets.
Smoke outlets connecting directly to the open air should be provided from every basement storey, except for any basement storey that has both of the following.
a. A maximum floor area of 200m2.
b. A floor a maximum of 3m below the adjacent ground level.
Basement storeys containing habitable rooms should have one of the following.
a. An emergency escape window or external door providing escape from the basement (paragraph 2.10).
b. A protected stairway (paragraph 2.5a) leading from the basement to a final exit.
A lift shaft serving storeys above ground level should not serve any basement, if either of the following applies.
a. There is only one escape stair serving storeys above ground level and smoke from a basement fire would adversely affect escape routes in the upper storeys.
b. The lift shaft is within the enclosure to an escape stair that terminates at ground level.
If a building does not meet the criteria of paragraph 3.28, an escape stair forming part of the only escape route from an upper storey should not continue down to serve a basement storey. The basement storey should be served by a separate escape stair.
Where multiple escape stairs serve the upper storeys, only one needs to end at ground level. Other stairs may connect with the basement storeys if there is a protected lobby or a protected corridor between the stairs and accommodation at each basement level.
The flights and landings of escape stairs should be constructed of materials achieving class A2-s3, d2 or better in all of the following situations.
a. If the escape stair is the only stair in a building with more than three storeys.
b. If the escape stair is within a basement storey.
c. If the escape stair serves any storey that has a floor level more than 18m above ground or access level.
d. If the escape stair is an external escape stair, except where the stair connects the ground storey or ground level with a floor or flat roof a maximum of 6m above or below ground level.
e. If the escape stair is a firefighting stair.
Materials achieving class B-s3, d2 or worse may be added to the top horizontal surface, except on firefighting stairs.
Basement storeys containing habitable rooms should have one of the following.
a. An emergency escape window or external door providing escape from the basement (see paragraph 3.6).
b. A protected stairway (minimum REI 30) leading from the basement to a final exit.
The following guidance should be used when applying the fire resistance standards in Table B4.
a. If one element of structure supports or carries or gives stability to another, the fire resistance
of the supporting element should be no less than the minimum period of fire resistance for the
other element (whether that other element is loadbearing or not). In some circumstances, it
may be reasonable to vary this principle, for example:
i. if the supporting structure is in the open air and is not likely to be affected by the fire in
the building
ii. if the supporting structure is in a different compartment, with a fire-separating element
(that has the higher standard of fire resistance) between the supporting and the separated
structure
iii. if a plant room on the roof needs greater fire resistance than the elements of structure
that support it.
b. If an element of structure forms part of more than one building or compartment, that element
should be constructed to the standard of the higher of the relevant provisions.
c. If, due to the slope of the ground, one side of a basement is open at ground level (allowing
smoke to vent and providing access for firefighting) for elements of structure in that storey
it may be appropriate to adopt the standard of fire resistance that applies to above-ground
structures.
d. Although most elements of structure in a single storey building may not need fire resistance,
fire resistance is needed if one of the following applies to the element.
i. It is part of, or supports, an external wall, and there is provision in the guidance on
requirement B4 to limit the extent of openings and other unprotected areas in the wall.
ii. It is part of, or supports, a compartment wall, including a wall that is common to two or
more buildings.
iii. It supports a gallery.
For the purposes of this paragraph, the ground storey of a building that has one or more basement storeys and no upper storeys may be considered as a single storey building. The fire resistance of the basement storeys should be that specified for basements.
bathroom
See para 3.18
NOTE: Bathrooms do not need to have fire doorsets provided that the bathroom is separated by fire resisting construction from the adjacent rooms.
bedspace
A gallery should comply with one of the following.
a. It should be provided with an alternative exit.
b. It should be provided with an emergency escape window, as described in paragraph 3.6, where the gallery floor is a maximum of 4.5m above ground level.
c. It should meet the conditions shown in Diagram 3.1.
See para 3.19
NOTE: The bedrooms are not classified as inner rooms because escape is possible in two directions.
Fire doorset
Fire resisting construction (minimum REI 30) between living and bedroom accommodation
Alternative exit
A building should provide access to more than one common stair if it does not meet the criteria for a single common stair (see paragraph 3.26 and 3.27).
Where a storey (or part of a building) is served by a single access stair, that stair may be external provided both of the following conditions are met.
a. The stair serves a floor not more than 6m above the ground level.
b. The stair meets the provisions in paragraph 3.68.
block
Each flat in a block should have alarms as set out in paragraphs 1.1 to 1.4. With effective compartmentation, a communal fire alarm system is not normally needed. In some buildings, detectors in common parts of the building may need to operate smoke control or other fire protection systems but do not usually sound an audible warning.
In student residences that are designed and occupied as a block of flats, separate automatic detection should be provided in each self-contained flat where all of the following apply.
a. A group of up to six students shares the flat.
b. Each flat has its own entrance door.
c. The compartmentation principles for flats in Section 7 have been followed.
Where a total evacuation strategy is adopted, the alarm system should follow the guidance for buildings other than dwellings in Volume 2 of Approved Document B.
To assist the fire service to identify each floor in a block of flats with a top storey more than 11m above ground level (see Diagram D6), floor identification signs and flat indicator signs should be provided.
In blocks of flats (purpose group 1(a)) with a top storey over 18m above ground level (see Diagram D6 in Appendix D) an evacuation alert system should be provided in accordance with BS 8629.
Blocks of flats (purpose group 1(a)) with a top storey more than 11m above ground level (see Diagram D6 in Appendix D) should be provided with a secure information box.
NOTE: Consideration should also be given to other buildings with large, complex or uncommon layouts where the provision of a secure information box may be beneficial.
Provisions are recommended to support a stay put evacuation strategy for blocks of flats. It is based on the principle that a fire is contained in the flat of origin and common escape routes are maintained relatively free from smoke and heat. It allows occupants, some of whom may require assistance to escape in the event of a fire, in other flats that are not affected to remain.
Sufficient protection to common means of escape is necessary to allow occupants to escape should they choose to do so or are instructed/aided to by the fire service. A higher standard of protection is therefore needed to ensure common escape routes remain available for a longer period than is provided in other buildings.
Except for two storey blocks of flats, all escape routes should have adequate artificial lighting. If the mains electricity power supply fails, escape lighting should illuminate the route (including external escape routes).
Blocks of flats with a top storey more than 11m above ground level (see Diagram D6) should be fitted with a sprinkler system throughout the building in accordance with Appendix E.
NOTE: Sprinklers should be provided within the individual flats, they do not need to be provided in the common areas such as stairs, corridors or landings when these areas are fire sterile.
boundary
The following assumptions enable a reasonable standard of resistance to the spread of fire to be specified.
a. The size of a fire depends on the compartmentation within the building. A fire may involve a complete compartment, but will not spread to other compartments.
b. The intensity of a fire is related to the building use, but can be moderated by a sprinkler system.
c. Fires in ‘residential’ and ‘assembly and recreation’ buildings (purpose groups 1, 2 and 5) represent a greater risk to life.
d. A building on the far side of the relevant boundary meets both of the following conditions.
i. Has a similar elevation to the one in question.
ii. Is the same distance as the one in question from the common boundary.
e. The radiated heat passing through any part of the fire resisting external wall may be discounted.
The following assumptions enable a reasonable standard of resistance to the spread of fire to be specified.
a. The size of a fire depends on the compartmentation within the building. A fire may involve a complete compartment, but will not spread to other compartments.
b. The intensity of a fire is related to the building use, but can be moderated by a sprinkler system.
c. Fires in ‘residential’ and ‘assembly and recreation’ buildings (purpose groups 1, 2 and 5) represent a greater risk to life.
d. A building on the far side of the relevant boundary meets both of the following conditions.
i. Has a similar elevation to the one in question.
ii. Is the same distance as the one in question from the common boundary.
e. The radiated heat passing through any part of the fire resisting external wall may be discounted.
Wall sufficiently distant from relevant boundary to be a 100% unprotected area
Wall on or very close to the relevant boundary: very limited amounts of unprotected area
Wall not on, or not very close to, but not sufficiently far from relevant boundary that it can be a wholly unprotected area
Amount of unprotected area dependent on distance from relevant boundary
See para 11.4
Wall sufficiently distant from relevant boundary to be a 100% unprotected area
Wall on or very close to the relevant boundary: very limited amounts of unprotected area
Wall not on, or not very close to, but not sufficiently far from relevant boundary that it can be a wholly unprotected area
Amount of unprotected area dependent on distance from relevant boundary
See para 11.4
This boundary coincides with and is therefore relevant to side A
The boundary is parallel to side B2
But the relevant boundary may be the centre line of a road, railway, canal or river
NOTES:
This boundary is at less than 80 degrees to side C and is therefore relevant to side C
This diagram sets out the rules that apply in respect of a boundary for it to be considered as a relevant boundary.
For a boundary to be relevant it should comply with one of the following:
a. Coincide with the side of the building (A).
b. Be parallel to the side of the building (B1 or B2).
c. Be at an angle of maximum 80 degrees to the side of the building (C).
This boundary is parallel to and therefore relevant to side B1
See para 11.5
This boundary coincides with and is therefore relevant to side A
The boundary is parallel to side B2
But the relevant boundary may be the centre line of a road, railway, canal or river
NOTES:
This boundary is at less than 80 degrees to side C and is therefore relevant to side C
This diagram sets out the rules that apply in respect of a boundary for it to be considered as a relevant boundary.
For a boundary to be relevant it should comply with one of the following:
a. Coincide with the side of the building (A).
b. Be parallel to the side of the building (B1 or B2).
c. Be at an angle of maximum 80 degrees to the side of the building (C).
This boundary is parallel to and therefore relevant to side B1
See para 11.5
NOTES:
The notional boundary should be set in the area between the two buildings using the following rules:
1. The notional boundary is assumed to exist in the space between the buildings and is positioned so that one of the buildings would comply with the provisions for space separation having regard to the amount of its unprotected area. In practice, if one of the buildings is existing, the position of the boundary will be set by the space separation factors for that building.
2. The siting of the new building, or the second building if both are new, can then be checked to see that it also complies, using the notional boundary as the relevant boundary for the second building.
Notional boundary
Site boundary
Compliance with the provisions for space separation in respect of building A
Compliance with the provisions for space separation in respect of building B
See para 11.5
NOTES:
The notional boundary should be set in the area between the two buildings using the following rules:
1. The notional boundary is assumed to exist in the space between the buildings and is positioned so that one of the buildings would comply with the provisions for space separation having regard to the amount of its unprotected area. In practice, if one of the buildings is existing, the position of the boundary will be set by the space separation factors for that building.
2. The siting of the new building, or the second building if both are new, can then be checked to see that it also complies, using the notional boundary as the relevant boundary for the second building.
Notional boundary
Site boundary
Compliance with the provisions for space separation in respect of building A
Compliance with the provisions for space separation in respect of building B
See para 11.5
The fire resistance of a wall depends on its distance from the relevant boundary (see Diagram 11.1). Separation distances are measured to boundaries to ensure that the location and design of buildings on adjoining sites have no influence on the building under consideration.
The fire resistance of a wall depends on its distance from the relevant boundary (see Diagram 11.1). Separation distances are measured to boundaries to ensure that the location and design of buildings on adjoining sites have no influence on the building under consideration.
The boundary that a wall faces is the relevant boundary (Diagram 11.2). It may be one of the following.
a. The site boundary.
b. The centre line of a space where further development is unlikely, such as a road, railway, canal or river.
c. An assumed notional boundary between two buildings on the same site (Diagram 11.3) where either of the following conditions is met.
i. One or both of the buildings are in the "residential" or "assembly and recreation" purpose groups (purpose group 1, 2 or 5).
ii. The buildings will be operated/managed by different organisations.
The boundary that a wall faces is the relevant boundary (Diagram 11.2). It may be one of the following.
a. The site boundary.
b. The centre line of a space where further development is unlikely, such as a road, railway, canal or river.
c. An assumed notional boundary between two buildings on the same site (Diagram 11.3) where either of the following conditions is met.
i. One or both of the buildings are in the "residential" or "assembly and recreation" purpose groups (purpose group 1, 2 or 5).
ii. The buildings will be operated/managed by different organisations.
Minimum distance (a) between side of building and relevant boundary (m) Maximum total area of unprotected areas (m2)
See para 11.18
Minimum distance (a) between side of building and relevant boundary (m) Maximum total area of unprotected areas (m2)
See para 11.18
NOTES:
Separation distances do not apply to the boundary between roofs of a pair of semi-detached dwellinghouses and to enclosed/covered walkways. However, see Diagram 5.2 if the roof passes over the top of a compartment wall.
Polycarbonate and uPVC rooflights that achieve a class C-s3, d2 rating by test may be regarded as having a BROOF(t4) designation.
1. The designation of external roof surfaces is explained in Appendix B.
2. Not acceptable on any of the following buildings.
a. Dwellinghouses in terraces of three or more dwellinghouses.
b. Any other buildings with a cubic capacity of more than 1500m3.
3. Acceptable on buildings not listed in (1) if both of the following apply.
a. Part of the roof has a maximum area of 3m2 and is a minimum of 1500mm from any similar part.
b. The roof between the parts is covered with a material rated class A2-s3, d2 or better.
NOTES:
Separation distances do not apply to the boundary between roofs of a pair of semi-detached dwellinghouses and to enclosed/covered walkways. However, see Diagram 5.2 if the roof passes over the top of a compartment wall.
Polycarbonate and uPVC rooflights that achieve a class C-s3, d2 rating by test may be regarded as having a BROOF(t4) designation.
1. The designation of external roof surfaces is explained in Appendix B.
2. Not acceptable on any of the following buildings.
a. Dwellinghouses in terraces of three or more dwellinghouses.
b. Any other buildings with a cubic capacity of more than 1500m3.
3. Acceptable on buildings not listed in (1) if both of the following apply.
a. Part of the roof has a maximum area of 3m2 and is a minimum of 1500mm from any similar part.
b. The roof between the parts is covered with a material rated class A2-s3, d2 or better.
Separation distance is the minimum distance from the roof, or part of the roof, to the relevant boundary (paragraph 11.4). Table 12.1 sets out separation distances by the type of roof covering and the size and use of the building.
In addition, roof covering products (and/or materials) defined in Commission Decision 2000/553/ EC of 6 September 2000, implementing Council Directive 89/106/EEC, can be considered to fulfil all of the requirements for the performance characteristic ‘external fire performance’ without the need for testing, provided that any national provisions on the design and execution of works are fulfilled, and can be used without restriction.
Separation distance is the minimum distance from the roof, or part of the roof, to the relevant boundary (paragraph 11.4). Table 12.1 sets out separation distances by the type of roof covering and the size and use of the building.
In addition, roof covering products (and/or materials) defined in Commission Decision 2000/553/ EC of 6 September 2000, implementing Council Directive 89/106/EEC, can be considered to fulfil all of the requirements for the performance characteristic ‘external fire performance’ without the need for testing, provided that any national provisions on the design and execution of works are fulfilled, and can be used without restriction.
bs 8895-2:2015 material
In buildings that include a ‘residential’ purpose (purpose groups 1 and 2) with a storey 11m or more in height (see Diagram D6 in Appendix D) balconies should meet either of the following conditions.
a. Only contain materials achieving class A1 or A2-s1, d0, except for any of the following.
i. Cavity trays when used between two leaves of masonry.
ii. Intumescent and fire-stopping materials where the inclusion of the materials is necessary to meet the requirements of Part B of Schedule 1 to the Building Regulations 2010.
iii. Membranes.
iv. Seals, gaskets, fixings, sealants and backer rods.
v. Thermal break materials where the inclusion of the materials is necessary to meet the thermal bridging requirements of Part L of Schedule 1 to the Building Regulations 2010.
vi. Any material achieving class A1fl or A2fl-s1 when it forms the top horizontal floor layer of a balcony and is provided with an imperforate substrate under it which extends to the full size of the class A1fl or A2fl-s1 material.
vii. Electrical installations.
viii. Fibre optic cables.
b. Achieve both of the following conditions.
Have an imperforate soffit which extends to the full area of the balcony, achieves a minimum REI 30 rating and is constructed of materials achieving class A2-s1, d0 or better.
ii. Materials achieving class B-s1, d0 or worse extending beyond the boundary of a single
compartment should include a band of material rated class A2-s1, d0 or better, a minimum of 300mm in width centred on that boundary line.
Where regulation 7(2) applies, that regulation prevails over all the provisions in this paragraph.
Regulation 7(1A) prohibits the use of relevant metal composite materials in the external walls of all buildings of any height.
Regulations 5(k) and 6(3) provide that, where the use of a building is changed such that the building becomes a building described in regulation 7(4), the construction of the external walls, and specified attachments, must be investigated and, where necessary, work must be carried out to ensure they only contain materials achieving class A2-s1, d0 or class A1, other than those exempted by regulation 7(3).
Particular attention is drawn to the following points.
a. Membranes used as part of the external wall construction above ground level should achieve a minimum of class B-s3, d0. Roofing membranes do not need to achieve a minimum of class A2-s1, d0 when used as part of a roof connecting to an external wall.
b. Internal linings should comply with the guidance provided in Section 4.
c. Any part of a roof should achieve the minimum performance as detailed in Section 12.
d. As per regulation 7(3), window frames and glass (including laminated glass) are exempted
from regulation 7(2). Window spandrel panels and infill panels must comply with regulation 7(2).
e. Thermal breaks are small elements used as part of the external wall construction to restrict
thermal bridging. There is no minimum performance for these materials. However, they
should not span two compartments and should be limited in size to the minimum required
to restrict the thermal bridging (the principal insulation layer is not to be regarded as a
thermal break).
f. Regulation 7(2) only applies to specified attachments. Shop front signs and similar attachments are
not covered by the requirements of regulation 7(2), although attention is drawn to paragraph 10.21g.
g. While regulation 7(2) applies to materials which become part of an external wall or specified
attachment, consideration should be given to other attachments to the wall which could
impact on the risk of fire spread over the wall.
h. Any material achieving class A1fl or A2fl-s1 in accordance with BS EN 13501-1 is exempted when it
meets both of the following conditions.
i. It forms the top horizontal floor layer of a balcony.
ii. It is provided with an imperforate substrate under it which extends to the full size of the
class A1fl or A2fl-s1 material.
Area of fire resisting wall with materials more than 1mm thick and with a reaction to fire performance worse than class B-s3, d2 = a x b
Area of wall counted as unprotected area = 0.5a x b
Area of fire resisting wall with materials having a reaction to fire performance better than class B-s3, d2
See para 11.7
Where a fire resisting external wall has an external surface material that is worse than class B-s3, d2 and is more than 1mm thick, that part of the wall should be classified as an unprotected area equating to half its area (Diagram 11.4).
‘Roof covering’ describes one or more layers of material, but not the roof structure as a whole.
NOTES:
None of the above designations are suitable for protected stairways.
Polycarbonate and uPVC rooflights that achieve a class C-s3, d2 rating by test (see paragraph 12.7) may be regarded as having a BROOF(t4) classification.
Where Diagram 5.2a or 5.2b applies, rooflights should be a minimum of 1500mm from the compartment wall.
If double-skinned or laminate products have upper and lower surfaces of different materials, the greater distance applies.
1. See also the guidance to requirement B2 in Section 4.
2. The designation of external roof surfaces is explained in Appendix B.
3. Single-skinned rooflight only, in the case of non-thermoplastic material.
4. The rooflight should also meet the provisions of Diagram 12.1.
NOTES:
None of the above designations are suitable for protected stairways.
Polycarbonate and uPVC rooflights that achieve a class C-s3, d2 rating by test (paragraph 12.7) may be regarded as having a BROOF(t4) classification.
Where Diagram 5.2a or 5.2b applies, rooflights should be a minimum of 1500mm from the compartment wall.
If double-skinned or laminate products have upper and lower surfaces of different materials, the greater distance applies.
1. See also the guidance to requirement B2 in section 4.
2. No limit in the case of any space described in 2a, b and c.
3. Single-skinned rooflight only, in the case of non-thermoplastic material.
4. The rooflight should also meet the provisions of diagram 12.1.
Table 12.3 sets the limitations for using thermoplastic materials with a TP(a) rigid or TP(b) (see also Diagram 12.1) classification. The method of classifying thermoplastic materials is given in Appendix B.
The highest National product performance classification for lining materials is Class O. This is achieved if a material or the surface of a composite product is either:
a. composed throughout of materials of limited combustibility; or
b. a Class 1 material which has a fire propagation index (I) of not more than 12 and sub-index (i1) of not more than 6.
Note: Class O is not a classification identified in any British Standard test.
The highest national product performance classification for lining materials is Class 0. This is achieved if a material or the surface of a composite product is either:
a. composed throughout of materials of limited combustibility; or
b. a Class 1 material which has a fire propagation index (I) of not more than 12 and sub-index (i1) of not more than 6.
Note: Class O is not a classification identified in any British Standard test.
The external envelope of a building should not provide a medium for fire spread if it is likely to be a risk to health or safety. The use of combustible materials for cladding framework, or of combustible thermal insulation as an overcladding or in ventilated cavities, may present such a risk in tall buildings, even though the provisions for external surfaces in Diagram 40 may have been satisfied.
In a building with a storey 18m or more above ground level, insulation material used in ventilated cavities in the external wall construction should be of limited combustibility (see Appendix A). This restriction does not apply to masonry cavity wall construction which complies with Diagram 32 in Section 10. Advice on the use of thermal insulation material is given in the BRE Report Fire performance of external thermal insulation for walls of multi-storey buildings (BR 135, 1988).
Thermoplastic materials that do not meet the classifications in Table 4.1 can be used as described in paragraphs 4.13 to 4.17. No guidance for European fire test performance is currently available, because there is no generally accepted test and classification procedure.
Thermoplastic materials are defined in Appendix B, paragraph B11. Classifications used here are explained in paragraph B13.
Materials within this zone – at plane of ceiling – should comply with Table 4.1
Rooflights
See Table 4.2
Guidance on the use of PTFE-based materials for tension-membrane roofs and structures is given in the BRE report BR 274.
Materials achieving class B-s3, d2 or worse used as a substrate to the roof covering and any timber tiling battens, fully bedded in mortar or other suitable material for the width of the wall (Diagram 5.2b), may extend over the compartment wall in buildings that are a maximum of 15m high.
Double-skinned insulated roof sheeting should incorporate a band of material rated class A2-s3, d2 or better, a minimum of 300mm in width, centred over the wall.
NOTES:
1. Materials used to close the cavity in this arrangement do not need to achieve a specific performance in relation to fire resistance.
2. Domestic meter cupboards may be installed provided that the following conditions are met:
a. There are no more than two cupboards per dwelling
b. The openings in the outer wall leaf are not bigger than 800X500mm for each cupboard
c. The inner leaf is not penetrated except by a sleeve not more than 80X80mm, which is fire-stopped.
3. Materials achieving class B-s3, d2 or worse may be placed within the cavity.
See para 5.18
Double-skinned insulated roof sheeting with a thermoplastic core should incorporate a band of material rated class A2-s3, d2 or better, a minimum of 300mm in width, centred over the wall.
Non-combustible materials are defined a. (National classes) when tested to BS 476: b. (European classes) when classified as class Table A6 identifies non-combustible products
in Table A6 either as listed products, or in terms
of performance:
Part 4:1970 Non-combustibility test for
materials or Part 11 :1982; or
A 1 in accordance with BS EN 13501-1 :2002
Fire classification of construction products
and building elements. Classification using
data from reaction to fire tests when tested
to BS EN ISO 1182:2002 Reaction to fire tests
for building products - Non-combustibility
test and BS EN ISO 1716:2002 Reaction to
fire tests for building products. Determination
of the gross calorific value.
and materials, and lists circumstances where
their use is necessary.
NOTES:
1. Materials used to close the cavity in this arrangement do not need to achieve a specific performance in relation to fire resistance.
2. Domestic meter cupboards may be installed provided that the following conditions are met:
a. There are no more than two cupboards per dwelling
b. The openings in the outer wall leaf are not bigger than 800X500mm for each cupboard
c. The inner leaf is not penetrated except by a sleeve not more than 80X80mm, which is fire-stopped.
3. Materials achieving class B-s3, d2 or worse may be placed within the cavity.
See para 8.3
Materials used for fire-stopping should be reinforced with (or supported by) materials rated class A2-s3, d2 or better to prevent displacement in both of the following cases.
a. Where the unsupported span is greater than 100mm.
b. Where non-rigid materials are used (unless subjected to appropriate fire resistance testing to show their suitability).
Other fire-stopping materials include the following. a. Cement mortar. b. Gypsum-based plaster. c. Cement-based or gypsum-based vermiculite/perlite mixes. d. Glass fibre, crushed rock, blast furnace slag or ceramic-based products (with or without resin binders). e. Intumescent mastics. These may be used in situations appropriate to the particular material. Not all materials will be suitable in every situation.
Thermoplastic material is any synthetic polymeric material that has a softening point below 200°C if tested to BS EN ISO 306 Method A120. Products formed from these materials cannot always be classified in the normal way. In those circumstances the following approach can be followed.
Thermoplastic materials used for window glazing, rooflights and lighting diffusers within suspended ceilings do not need to meet the criteria within paragraph B19 onwards, if the guidance to requirements B2 and B4 is followed.
For the purposes of requirements B2 and B4, thermoplastic materials should be classified as TP(a)
rigid, TP(a) flexible or TP(b), as follows:
a. TP(a) rigid
i. rigid solid uPVC sheet
ii. solid (as distinct from double- or multi-skinned) polycarbonate sheet a minimum of 3mm
thick
iii. multi-skinned rigid sheet made from uPVC or polycarbonate that has a class 1 rating when
tested to BS 476-7
iv. any other rigid thermoplastic product, a specimen of which (at the thickness of the
product as put on the market), when tested to BS 2782-0 Method 508A, performs so that
both:
• the test flame extinguishes before the first mark
• the duration of flaming or afterglow does not exceed 5 seconds following removal of
the burner.
b. TP(a) flexible
Flexible products a maximum of 1mm thick that comply with the Type C requirements
of BS 5867-2 when tested to BS 5438 Test 2 with the flame applied to the surface of the
specimens for 5, 15, 20 and 30 seconds respectively, but excluding the cleansing procedure; and
c. TP(b)
i. rigid solid polycarbonate sheet products a maximum of 3mm thick, or multi-skinned
polycarbonate sheet products that do not qualify as TP(a) by test
ii. other products which, when a specimen of the material between 1.5 and 3mm thick is
tested in accordance with BS 2782-0 Method 508A, have a maximum rate of burning of
50mm/minute.
NOTE: If it is not possible to cut or machine a 3mm thick specimen from the product, then a 3mm
A thermoplastic material alone when used as a lining to a wall or ceiling cannot be assumed to protect a substrate. The surface rating of both thermoplastic material and substrate must therefore meet the required classification. If, however, the thermoplastic material is fully bonded to a non-thermoplastic substrate, then only the surface rating of the composite needs to meet the required classification.
Unless shown to be satisfactory when tested as part of a fire doorset assembly, the essential components of any hinge on which a fire door is hung should be made entirely from materials that have a minimum melting point of 800°C.
building
B3.(1) The building shall be designed and constructed so that, in the event of fire, its stability will be maintained for a reasonable period
(2) A wall common to two or more buildings shall be designed and constructed so that it adequately resists the spread of fire between those buildings.
For the purposes of this sub-paragraph a house in a terrace and a semi-detached house are each to be treated as a separate building.
(3) Where reasonably necessary to inhibit the spread of fire within the building, measures shall be taken, to an extent appropriate to the size and intended use of the building, comprising either or both of the following—
(a) sub-division of the building with fire-resisting construction;
(b) installation of suitable automatic fire suppression systems.
(4) The building shall be designed and constructed so that the unseen spread of fire and smoke within concealed spaces in its structure and fabric is inhibited.
Requirement B3(3) does not apply to material alterations to any prison provided under section 33 of the Prison Act 1952.
The external envelope of a building should not contribute to undue fire spread from one part of a
building to another part. This intention can be met by constructing external walls so that both of
the following are satisfied.
a. The risk of ignition by an external source to the outside surface of the building and spread of
fire over the outside surface is restricted.
b. The materials used to construct external walls, and attachments to them, and how they are
assembled do not contribute to the rate of fire spread up the outside of the building.
The extent to which this is necessary depends on the height and use of the building.
The external envelope of a building should not contribute to undue fire spread from one part of a
building to another part. This intention can be met by constructing external walls so that both of
the following are satisfied.
a. The risk of ignition by an external source to the outside surface of the building and spread of
fire over the outside surface is restricted.
b. The materials used to construct external walls, and attachments to them, and how they are
assembled do not contribute to the rate of fire spread up the outside of the building.
The extent to which this is necessary depends on the height and use of the building.
The external envelope of a building should not provide a medium for undue fire spread to
adjacent buildings or be readily ignited by fires in adjacent buildings. This intention can be met by
constructing external walls so that all of the following are satisfied.
a. The risk of ignition by an external source to the outside surface of the building is restricted.
b. The amount of thermal radiation that falls on a neighbouring building from window openings
and other unprotected areas in the building on fire is not enough to start a fire in the other
building.
c. Flame spread over the roof and/or fire penetration from external sources through the roof is
restricted.
The extent to which this is necessary depends on the use of the building and its position in relation
to adjacent buildings and therefore the site boundary.
The external envelope of a building should not provide a medium for undue fire spread to
adjacent buildings or be readily ignited by fires in adjacent buildings. This intention can be met by
constructing external walls so that all of the following are satisfied.
a. The risk of ignition by an external source to the outside surface of the building is restricted.
b. The amount of thermal radiation that falls on a neighbouring building from window openings
and other unprotected areas in the building on fire is not enough to start a fire in the other
building.
c. Flame spread over the roof and/or fire penetration from external sources through the roof is
restricted.
The extent to which this is necessary depends on the use of the building and its position in relation
to adjacent buildings and therefore the site boundary.
The aim of this regulation is to ensure that the person responsible for the building has sufficient
information relating to fire safety to enable them to manage the building effectively. The aim of
regulation 38 will be achieved when the person responsible for the building has all the information
to enable them to do all of the following.
a. Understand and implement the fire safety strategy of the building.
b. Maintain any fire safety system provided in the building.
c. Carry out an effective fire risk assessment of the building.
Provisions covering access and facilities for the fire service are to safeguard the health and safety of
people in and around the building. Their extent depends on the size and use of the building. Most
firefighting is carried out within the building. In the Secretary of State’s view, requirement B5 is met
by achieving all of the following.
a. External access enabling fire appliances to be used near the building.
b. Access into and within the building for firefighting personnel to both:
i. search for and rescue people
ii. fight fire.
c. Provision for internal fire facilities for firefighters to complete their tasks.
d. Ventilation of heat and smoke from a fire in a basement.
If an alternative approach is taken to providing the means of escape, outside the scope of this
approved document, additional provisions for firefighting access may be required. Where deviating
from the general guidance, it is advisable to seek advice from the fire and rescue service as early as
possible (even if there is no statutory duty to consult).
e. A facility to store building information for firefighters to complete their tasks.
Provisions covering access and facilities for the fire service are to safeguard the health and safety of
people in and around the building. Their extent depends on the size and use of the building. Most
firefighting is carried out within the building. In the Secretary of State’s view, requirement B5 is met
by achieving all of the following.
a. External access enabling fire appliances to be used near the building.
b. Access into and within the building for firefighting personnel to both:
i. search for and rescue people
ii. fight fire.
c. Provision for internal fire facilities for firefighters to complete their tasks.
d. Ventilation of heat and smoke from a fire in a basement.
If an alternative approach is taken to providing the means of escape, outside the scope of this
approved document, additional provisions for firefighting access may be required. Where deviating
from the general guidance, it is advisable to seek advice from the fire and rescue service as early as
possible (even if there is no statutory duty to consult).
e. A facility to store building information for firefighters to complete their tasks.
Building uses are classified within different purpose groups, which represent different levels of hazard (see Table 0.1). A purpose group can apply to a whole building or a compartment within the building, and should relate to the main use of the building or compartment.
Building uses are classified within different purpose groups, which represent different levels of hazard (see Table 0.1). A purpose group can apply to a whole building or a compartment within the building, and should relate to the main use of the building or compartment.
Where a building or compartment has more than one use, it is appropriate to assign each different use to its own purpose group in the following situations.
a. If the ancillary use is a flat.
b. If both of the following apply.
i. The building or compartment has an area of more than 280m2.
ii. The ancillary use relates to an area that is more than one-fifth of the total floor area of the building or compartment.
c. In ‘shop and commercial’ (purpose group 4) buildings or compartments, if the ancillary use is storage and both of the following apply.
i. The building or compartment has an area of more than 280m2.
ii. The storage area comprises more than one-third of the total floor area of the building or compartment.
Where a building or compartment has more than one use, it is appropriate to assign each different use to its own purpose group in the following situations.
a. If the ancillary use is a flat.
b. If both of the following apply.
i. The building or compartment has an area of more than 280m2.
ii. The ancillary use relates to an area that is more than one-fifth of the total floor area of the building or compartment.
c. In ‘shop and commercial’ (purpose group 4) buildings or compartments, if the ancillary use is storage and both of the following apply.
i. The building or compartment has an area of more than 280m2.
ii. The storage area comprises more than one-third of the total floor area of the building or compartment.
This approved document includes reference to selected guidance for buildings other than dwellings. For the design of mixed use buildings, Approved Document B Volume 2 should be consulted in addition to the guidance contained in this approved document.
This approved document includes reference to selected guidance for buildings other than dwellings. For the design of mixed use buildings, Approved Document B Volume 2 should be consulted in addition to the guidance contained in this approved document.
The provisions in this document have the following aims.
Requirement B1: When there is a fire, ensure both:
a. satisfactory means of sounding an alarm
b. satisfactory means of escape for people.
Requirement B2: Inhibit the spread of fire over internal linings of buildings.
Requirement B3: The building must be built such that all of the following are achieved in the event of a fire:
a. the premature collapse of the building is avoided
b. sufficient fire separation is provided within buildings and between adjoining buildings
c. automatic fire suppression is provided where necessary
d. the unseen spread of fire and smoke in cavities is restricted.
Requirement B4: Restrict both:
a. the potential for fire to spread over external walls and roofs (including compliance with regulations 6(4) and 7(2))
b. the spread of fire from one building to another.
Requirement B5: Ensure both:
a. satisfactory access for the fire service and its appliances
b. facilities in buildings to help firefighters save the lives of people in and around buildings.
Regulation 38: Provide fire safety information to building owners.
The provisions in this document have the following aims.
Requirement B1: When there is a fire, ensure both:
a. satisfactory means of sounding an alarm
b. satisfactory means of escape for people.
Requirement B2: Inhibit the spread of fire over internal linings of buildings.
Requirement B3: The building must be built such that all of the following are achieved in the event of a fire:
a. the premature collapse of the building is avoided
b. sufficient fire separation is provided within buildings and between adjoining buildings
c. automatic fire suppression is provided where necessary
d. the unseen spread of fire and smoke in cavities is restricted.
Requirement B4: Restrict both:
a. the potential for fire to spread over external walls and roofs (including compliance with regulations 6(4) and 7(2))
b. the spread of fire from one building to another.
Requirement B5: Ensure both:
a. satisfactory access for the fire service and its appliances
b. facilities in buildings to help firefighters save the lives of people in and around buildings.
Regulation 38: Provide fire safety information to building owners.
The Building Regulations do not impose any requirements on the management of a building, but do assume that it will be properly managed. This includes, for example, keeping protected escape routes virtually ‘fire sterile’.
Appropriate fire safety design considers the way in which a building will be managed. Any reliance on an unrealistic or unsustainable management regime cannot be considered to have met the requirements of the regulations.
Once the building is in use, the management regime should be maintained and a suitable risk assessment undertaken for any variation in that regime. Failure to take proper management responsibility may result in the prosecution of an employer, building owner or occupier under legislation such as the Regulatory Reform (Fire Safety) Order 2005.
The fire safety aspects of the Building Regulations aim to achieve reasonable standards of health and safety for people in and around buildings. People, regardless of ability, age or gender, should be able to access buildings and use their facilities. The fire safety measures incorporated into a building should take account of the needs of everyone who may access the building, both as visitors and as people who live or work in it. It is not appropriate, except in exceptional circumstances, to assume that certain groups of people will be excluded from a building because of its use. The provisions in this approved document are considered to be of a reasonable standard for most buildings. However, some people’s specific needs might not be addressed. In some situations, additional measures may be needed to accommodate these needs. This should be done on a case- by-case basis.
The fire safety requirements of the Building Regulations will probably be satisfied by following the relevant guidance in this approved document. However, approved documents provide guidance for some common building situations, and there may be alternative methods of complying with the Building Regulation requirements. If alternative methods are adopted, the overall level of safety should not be lower than the approved document provides. It is the responsibility of those undertaking the work to demonstrate compliance. If other standards or guidance documents are adopted, the relevant fire safety recommendations in those publications should be followed in their entirety. However, in some circumstances it may be necessary to use one publication to supplement another. Care must be taken when using supplementary guidance to ensure that an integrated approach is used in any one building. Guidance documents intended specifically for assessing fire safety in existing buildings often include less onerous provisions than those for new buildings and are therefore unlikely to be appropriate for building work that is controlled by the Building Regulations. Buildings for industrial and commercial activities that present a special fire hazard, e.g. those that sell fuels, may require additional fire precautions to those in this approved document.
The external wall of a building should not provide a medium for fire spread if that is likely to be a risk to health and safety. Combustible materials and cavities in external walls and attachments to them can present such a risk, particularly in tall buildings. The guidance in this section is designed to reduce the risk of fire spread as well as the risk of ignition from flames coming from adjacent buildings.
The external wall of a building should not provide a medium for fire spread if that is likely to be a risk to health and safety. Combustible materials and cavities in external walls and attachments to them can present such a risk, particularly in tall buildings. The guidance in this section is designed to reduce the risk of fire spread as well as the risk of ignition from flames coming from adjacent buildings.
Regulation 7(1)(a) requires that materials used in building work are appropriate for the circumstances in which they are used. Regulation 7(2) sets requirements in respect of external walls and specified attachments in relevant buildings.
NOTE: Further guidance on regulation 7(1) can be found in HM Government’s Manual to the Building Regulations.
Regulation 7(1)(a) requires that materials used in building work are appropriate for the circumstances in which they are used. Regulation 7(2) sets requirements in respect of external walls and specified attachments in relevant buildings.
NOTE: Further guidance on regulation 7(1) can be found in HM Government’s Manual to the Building Regulations.
Regulation 7(2) applies to any building with a storey at least 18m above ground level (as
measured in accordance with Diagram D6 in Appendix D) and which contains one or more
dwellings; an institution; or a room for residential purposes. It requires that all materials which become part of an external wall or specified attachment achieve class A2-s1, d0 or class A1 in accordance with BS EN 13501-1, other than those exempted by regulation 7(3).
NOTE: The above includes student accommodation, care homes, sheltered housing, hospitals, dormitories in boarding schools, hotels, hostels and boarding houses. See regulation 7(4) for the definition of relevant buildings.
NOTE: Transposition to national class (Table B1) does not apply to the classification in this paragraph.
NOTES:
The notional boundary should be set in the area between the two buildings using the following rules:
1. The notional boundary is assumed to exist in the space between the buildings and is positioned so that one of the buildings would comply with the provisions for space separation having regard to the amount of its unprotected area. In practice, if one of the buildings is existing, the position of the boundary will be set by the space separation factors for that building.
2. The siting of the new building, or the second building if both are new, can then be checked to see that it also complies, using the notional boundary as the relevant boundary for the second building.
Notional boundary
Site boundary
Compliance with the provisions for space separation in respect of building A
Compliance with the provisions for space separation in respect of building B
See para 11.5
NOTE: Projections from the building line, such as a canopy or a loading platform, can be ignored when assessing separation distance. This does not apply where the canopy is enclosed by side walls.
Distance to relevant boundary measured from building line
See para 11.12
NOTE: Projections from the building line, such as a canopy or a loading platform, can be ignored when assessing separation distance. This does not apply where the canopy is enclosed by side walls.
Distance to relevant boundary measured from building line
See para 11.12
For buildings fitted with dry fire mains, both of the following apply.
a. Access should be provided for a pumping appliance to within 18m of each fire main inlet connection point. Inlets should be on the face of the building.
b. The fire main inlet connection point should be visible from the parking position of the appliance, and meet the provisions in Section 8 of BS 9990.
For buildings fitted with dry fire mains, both of the following apply.
a. Access should be provided for a pumping appliance to within 18m of each fire main inlet connection point. Inlets should be on the face of the building.
b. The fire main inlet connection point should be visible from the parking position of the appliance, and meet the provisions in Section 8 of BS 9990.
The external envelope of a building should not provide a medium for fire spread if it is likely to be a risk to health or safety. The use of combustible materials for cladding framework, or of combustible thermal insulation as an overcladding or in ventilated cavities, may present such a risk in tall buildings, even though the provisions for external surfaces in Diagram 40 may have been satisfied.
In a building with a storey 18m or more above ground level, insulation material used in ventilated cavities in the external wall construction should be of limited combustibility (see Appendix A). This restriction does not apply to masonry cavity wall construction which complies with Diagram 32 in Section 10. Advice on the use of thermal insulation material is given in the BRE Report Fire performance of external thermal insulation for walls of multi-storey buildings (BR 135, 1988).
Buildings with a storey more than 50m above fire service vehicle access level should be provided with wet fire mains. In all other buildings where fire mains are provided, either wet or dry fire mains are suitable.
A building with basement storeys should have firefighting shafts in accordance with the following.
a. There is a basement more than 10m below the fire and rescue service vehicle access level. The firefighting shafts should contain firefighting lifts.
b. There are two or more basement storeys, each with a minimum area of 900m2. The firefighting shafts do not need to include firefighting lifts.
The building’s height and size determine whether firefighting shafts also serve upper storeys.
A building with basement storeys should have firefighting shafts in accordance with the following.
a. There is a basement more than 10m below the fire and rescue service vehicle access level. The firefighting shafts should contain firefighting lifts.
b. There are two or more basement storeys, each with a minimum area of 900m2. The firefighting shafts do not need to include firefighting lifts.
The building’s height and size determine whether firefighting shafts also serve upper storeys.
In buildings where a firefighting shaft is required, a minimum of two firefighting shafts should be provided in either of the following situations.
a. A building that has both of the following.
i. A storey with a floor area of 900m2 or more.
ii. A storey 18m or more above the fire and rescue service vehicle access level.
b. A building with a basement storey which is more than 900m2.
In buildings where a firefighting shaft is required, a minimum of two firefighting shafts should be provided in either of the following situations.
a. A building that has both of the following.
i. A storey with a floor area of 900m2 or more.
ii. A storey 18m or more above the fire and rescue service vehicle access level.
b. A building with a basement storey which is more than 900m2.
For building work involving the erection or extension of a relevant building (i.e. a building to which the Regulatory Reform (Fire Safety) Order 2005 applies, or will apply), or the relevant change of use of a building, fire safety information should be given to the responsible person at one of the following times.
a. When the project is complete.
b. When the building or extension is first occupied.
Work should comply with Parts K and L of Schedule 1 to the Building Regulations. When complete, the building should comply with other applicable parts of Schedule 1 to at least the same level as before.
Work should comply with Parts K and L of Schedule 1 to the Building Regulations. When complete, the building should comply with other applicable parts of Schedule 1 to at least the same level as before.
In buildings with more than three storeys above the ground storey, stairs may serve the flats and other occupancies if all of the following apply.
a. The flat is ancillary to the main use of the building.
b. The flat has an independent alternative escape route.
c. The stair is separated from occupancies on lower storeys by a protected lobby (minimum REI 30) at each of those storeys.
d. The stair enclosure has at least the same standard of fire resistance as the structural elements of the building (see Appendix B, Table B4); if the stair is a firefighting stair, it should comply with the provisions in Section 15 (see also paragraph 3.60).
e. Any automatic fire detection and alarm system fitted in the main part of the building also covers all flats.
f. Any security measures in any parts of the building do not prevent escape at all material times.
a. SMALL SINGLE STAIR BUILDING
*If smoke control is provided in the lobby, the travel distance can be increased to 7.5m maximum(see Diagram 3.7, example b).
b. SMALL SINGLE STAIR BUILDING WITH NO MORE THAN TWO FLATS PER STOREY
The door between stair and lobby should be free from security fastenings.
If the flats have protected entrance halls, the lobby between the common stair and flat entrance is not essential.
NOTES:
1. The arrangements shown also apply to the top storey.
2. If the travel distance across the lobby in diagram (a) exceeds 4.5m, Diagram 3.7 applies.
3. Where,in Diagram (b), the lobby between the common stair and the dwelling is omitted in smal lsingle stair buildings, an automatic opening vent with a free area of at least 1m2 is required at the top of the stair,which is operated automatically on detection of smoke at any storey in the stair.
4. For further guidance on the fire rating of the fire doorsets from the corridor to the flat and/or stairway refer to Appendix C, Table C1.
Fire resisting construction
Openable vent at high level for fire service use (1.0m2 minimum free area); see paragraph 3.28eSee para 3.28
Diagram 3.9
Adjoining buildings should only be separated by walls, not floors. Compartment walls common to two or more buildings should comply with both of the following.
a. Run the full height of the building in a continuous vertical plane.
b. Be continued through any roof space to the underside of the roof (see Diagram 5.2).
Adjoining buildings should only be separated by walls, not floors. Compartment walls common to two or more buildings should comply with both of the following.
a. Run the full height of the building in a continuous vertical plane.
b. Be continued through any roof space to the underside of the roof (see Diagram 5.2).
Adjoining buildings should only be separated by walls, not floors. Compartment walls common to two or more buildings should comply with both of the following.
a. Run the full height of the building in a continuous vertical plane.
b. Be continued through any roof space to the underside of the roof (see Diagram 5.2).
Adjoining buildings should only be separated by walls, not floors. Compartment walls common to two or more buildings should comply with both of the following.
a. Run the full height of the building in a continuous vertical plane.
b. Be continued through any roof space to the underside of the roof (see Diagram 5.2).
Ductwork should not help to transfer fire and smoke through the building. Terminals of exhaust points should be sited away from final exits, cladding or roofing materials achieving class B-s3, d2 or worse and openings into the building.
Ductwork should not help to transfer fire and smoke through the building. Terminals of exhaust points should be sited away from final exits, cladding or roofing materials achieving class B-s3, d2 or worse and openings into the building.
The standards of fire resistance necessary for a particular building are based on assumptions about the severity of fires and the consequences should an element fail. Fire severity is estimated in very broad terms from the use of the building (its purpose group), on the assumption that the building contents (which constitute the fire load) are similar for buildings with the same use.
The standards of fire resistance necessary for a particular building are based on assumptions about the severity of fires and the consequences should an element fail. Fire severity is estimated in very broad terms from the use of the building (its purpose group), on the assumption that the building contents (which constitute the fire load) are similar for buildings with the same use.
The number of occupants of a room, storey, building or part of a building is either of the following.
a. The maximum number of people it is designed to hold.
b. In buildings other than dwellings, the number of people calculated by dividing the area of
a room or storey(s) (m2) by a floor space factor (m2 per person) such as given in Table D1 for
guidance.
The number of occupants of a room, storey, building or part of a building is either of the following.
a. The maximum number of people it is designed to hold.
b. In buildings other than dwellings, the number of people calculated by dividing the area of
a room or storey(s) (m2) by a floor space factor (m2 per person) such as given in Table D1 for
guidance.
Where required, sprinkler systems should be provided throughout the building or separated part,
unless acting as a compensatory feature to address a specific risk. They should be designed and
installed in accordance with the following.
a. For residential buildings, the requirements of BS 9251.
b. For non-residential buildings, or residential buildings outside the scope of BS 9251, the
requirements of BS EN 12845, including the relevant hazard classification together with
additional measures to improve system reliability and availability as described in Annex F of the
standard.
NOTE: Any sprinkler system installed to satisfy the requirements of Part B of the Building
Regulations should be provided with additional measures to improve system reliability and
availability and is therefore to be regarded as a life safety system. However, there may be some
circumstances in which additional measures to improve system reliability and availability specified
in Annex F of BS EN 12845 are inappropriate or unnecessary.
building act
Where required, sprinkler systems should be provided throughout the building or separated part,
unless acting as a compensatory feature to address a specific risk. They should be designed and
installed in accordance with the following.
a. For residential buildings, the requirements of BS 9251.
b. For non-residential buildings, or residential buildings outside the scope of BS 9251, the
requirements of BS EN 12845, including the relevant hazard classification together with
additional measures to improve system reliability and availability as described in Annex F of the
standard.
NOTE: Any sprinkler system installed to satisfy the requirements of Part B of the Building
Regulations should be provided with additional measures to improve system reliability and
availability and is therefore to be regarded as a life safety system. However, there may be some
circumstances in which additional measures to improve system reliability and availability specified
in Annex F of BS EN 12845 are inappropriate or unnecessary.
building and land associated with the building
People should be able to rapidly leave the area around the building. Direct access to a street, passageway, walkway or open space should be available. The route away from the building should comply with the following.
a. Be well defined.
b. If necessary, have suitable guarding.
building control body
NOTES:
1. Fire appliances are not standardised. The building control body may, in consultation with the local fire and rescue service, use other dimensions.
2. The road base can be designed to 12.5 tonne capacity. Structures such as bridges should have the full 17-tonne capacity. The weight of high reach appliances is distributed over a number of axles, so infrequent use of a route designed to accommodate 12.5 tonnes should not cause damage.
NOTES:
1. Fire appliances are not standardised. The building control body may, in consultation with the local fire and rescue service, use other dimensions.
2. The road base can be designed to 12.5 tonne capacity. Structures such as bridges should have the full 17-tonne capacity. The weight of high reach appliances is distributed over a number of axles, so infrequent use of a route designed to accommodate 12.5 tonnes should not cause damage.
building regulations
Regulation 7(1A) prohibits the use of relevant metal composite materials in the external walls of all buildings of any height.
Regulation 7(1)(a) requires that materials used in building work are appropriate for the circumstances in which they are used. Regulation 7(2) sets requirements in respect of external walls and specified attachments in relevant buildings.
NOTE: Further guidance on regulation 7(1) can be found in HM Government’s Manual to the Building Regulations.
building regulations 2010
The provisions in this document have the following aims.
Requirement B1: When there is a fire, ensure both:
a. satisfactory means of sounding an alarm
b. satisfactory means of escape for people.
Requirement B2: Inhibit the spread of fire over internal linings of buildings.
Requirement B3: The building must be built such that all of the following are achieved in the event of a fire:
a. the premature collapse of the building is avoided
b. sufficient fire separation is provided within buildings and between adjoining buildings
c. automatic fire suppression is provided where necessary
d. the unseen spread of fire and smoke in cavities is restricted.
Requirement B4: Restrict both:
a. the potential for fire to spread over external walls and roofs (including compliance with regulations 6(4) and 7(2))
b. the spread of fire from one building to another.
Requirement B5: Ensure both:
a. satisfactory access for the fire service and its appliances
b. facilities in buildings to help firefighters save the lives of people in and around buildings.
Regulation 38: Provide fire safety information to building owners.
The fire safety requirements of the Building Regulations will probably be satisfied by following the relevant guidance in this approved document. However, approved documents provide guidance for some common building situations, and there may be alternative methods of complying with the Building Regulation requirements. If alternative methods are adopted, the overall level of safety should not be lower than the approved document provides. It is the responsibility of those undertaking the work to demonstrate compliance. If other standards or guidance documents are adopted, the relevant fire safety recommendations in those publications should be followed in their entirety. However, in some circumstances it may be necessary to use one publication to supplement another. Care must be taken when using supplementary guidance to ensure that an integrated approach is used in any one building. Guidance documents intended specifically for assessing fire safety in existing buildings often include less onerous provisions than those for new buildings and are therefore unlikely to be appropriate for building work that is controlled by the Building Regulations. Buildings for industrial and commercial activities that present a special fire hazard, e.g. those that sell fuels, may require additional fire precautions to those in this approved document.
In buildings that include a ‘residential’ purpose (purpose groups 1 and 2) with a storey 11m or more in height (see Diagram D6 in Appendix D) balconies should meet either of the following conditions.
a. Only contain materials achieving class A1 or A2-s1, d0, except for any of the following.
i. Cavity trays when used between two leaves of masonry.
ii. Intumescent and fire-stopping materials where the inclusion of the materials is necessary to meet the requirements of Part B of Schedule 1 to the Building Regulations 2010.
iii. Membranes.
iv. Seals, gaskets, fixings, sealants and backer rods.
v. Thermal break materials where the inclusion of the materials is necessary to meet the thermal bridging requirements of Part L of Schedule 1 to the Building Regulations 2010.
vi. Any material achieving class A1fl or A2fl-s1 when it forms the top horizontal floor layer of a balcony and is provided with an imperforate substrate under it which extends to the full size of the class A1fl or A2fl-s1 material.
vii. Electrical installations.
viii. Fibre optic cables.
b. Achieve both of the following conditions.
Have an imperforate soffit which extends to the full area of the balcony, achieves a minimum REI 30 rating and is constructed of materials achieving class A2-s1, d0 or better.
ii. Materials achieving class B-s1, d0 or worse extending beyond the boundary of a single
compartment should include a band of material rated class A2-s1, d0 or better, a minimum of 300mm in width centred on that boundary line.
Where regulation 7(2) applies, that regulation prevails over all the provisions in this paragraph.
Regulation 7(1A) prohibits the use of relevant metal composite materials in the external walls of all buildings of any height.
Regulation 7(1)(a) requires that materials used in building work are appropriate for the circumstances in which they are used. Regulation 7(2) sets requirements in respect of external walls and specified attachments in relevant buildings.
NOTE: Further guidance on regulation 7(1) can be found in HM Government’s Manual to the Building Regulations.
Regulation 7(2) applies to any building with a storey at least 18m above ground level (as
measured in accordance with Diagram D6 in Appendix D) and which contains one or more
dwellings; an institution; or a room for residential purposes. It requires that all materials which become part of an external wall or specified attachment achieve class A2-s1, d0 or class A1 in accordance with BS EN 13501-1, other than those exempted by regulation 7(3).
NOTE: The above includes student accommodation, care homes, sheltered housing, hospitals, dormitories in boarding schools, hotels, hostels and boarding houses. See regulation 7(4) for the definition of relevant buildings.
NOTE: Transposition to national class (Table B1) does not apply to the classification in this paragraph.
Regulations 5(k) and 6(3) provide that, where the use of a building is changed such that the building becomes a building described in regulation 7(4), the construction of the external walls, and specified attachments, must be investigated and, where necessary, work must be carried out to ensure they only contain materials achieving class A2-s1, d0 or class A1, other than those exempted by regulation 7(3).
building regulations guidance
The fire safety requirements of the Building Regulations will probably be satisfied by following the relevant guidance in this approved document. However, approved documents provide guidance for some common building situations, and there may be alternative methods of complying with the Building Regulation requirements. If alternative methods are adopted, the overall level of safety should not be lower than the approved document provides. It is the responsibility of those undertaking the work to demonstrate compliance. If other standards or guidance documents are adopted, the relevant fire safety recommendations in those publications should be followed in their entirety. However, in some circumstances it may be necessary to use one publication to supplement another. Care must be taken when using supplementary guidance to ensure that an integrated approach is used in any one building. Guidance documents intended specifically for assessing fire safety in existing buildings often include less onerous provisions than those for new buildings and are therefore unlikely to be appropriate for building work that is controlled by the Building Regulations. Buildings for industrial and commercial activities that present a special fire hazard, e.g. those that sell fuels, may require additional fire precautions to those in this approved document.
Regulation 7(1)(a) requires that materials used in building work are appropriate for the circumstances in which they are used. Regulation 7(2) sets requirements in respect of external walls and specified attachments in relevant buildings.
NOTE: Further guidance on regulation 7(1) can be found in HM Government’s Manual to the Building Regulations.
building regulations uk part l
In buildings that include a ‘residential’ purpose (purpose groups 1 and 2) with a storey 11m or more in height (see Diagram D6 in Appendix D) balconies should meet either of the following conditions.
a. Only contain materials achieving class A1 or A2-s1, d0, except for any of the following.
i. Cavity trays when used between two leaves of masonry.
ii. Intumescent and fire-stopping materials where the inclusion of the materials is necessary to meet the requirements of Part B of Schedule 1 to the Building Regulations 2010.
iii. Membranes.
iv. Seals, gaskets, fixings, sealants and backer rods.
v. Thermal break materials where the inclusion of the materials is necessary to meet the thermal bridging requirements of Part L of Schedule 1 to the Building Regulations 2010.
vi. Any material achieving class A1fl or A2fl-s1 when it forms the top horizontal floor layer of a balcony and is provided with an imperforate substrate under it which extends to the full size of the class A1fl or A2fl-s1 material.
vii. Electrical installations.
viii. Fibre optic cables.
b. Achieve both of the following conditions.
Have an imperforate soffit which extends to the full area of the balcony, achieves a minimum REI 30 rating and is constructed of materials achieving class A2-s1, d0 or better.
ii. Materials achieving class B-s1, d0 or worse extending beyond the boundary of a single
compartment should include a band of material rated class A2-s1, d0 or better, a minimum of 300mm in width centred on that boundary line.
Where regulation 7(2) applies, that regulation prevails over all the provisions in this paragraph.
Work should comply with Parts K and L of Schedule 1 to the Building Regulations. When complete, the building should comply with other applicable parts of Schedule 1 to at least the same level as before.
Common to all of the provisions of Part B of the Building Regulations is the property of fire
resistance. Fire resistance is a measure of one or more of the following.
a. Resistance to collapse (loadbearing capacity), which applies to loadbearing elements only,
denoted R in the European classification of the resistance to fire performance.
b. Resistance to fire penetration (integrity), denoted E in the European classification of the
resistance to fire performance.
c. Resistance to the transfer of excessive heat (insulation), denoted I in the European
classification of the resistance to fire performance.
building safety
Fire safety information 38.
(1) This regulation applies where building work—
(a) consists of or includes the erection or extension of a relevant building; or
(b) is carried out in connection with a relevant change of use of a building, and Part B of Schedule 1 imposes a requirement in relation to the work.
(2) The person carrying out the work shall give fire safety information to the responsible person not later than the date of completion of the work, or the date of occupation of the building or extension, whichever is the earlier.
(3) In this regulation—
(a) “fire safety information” means information relating to the design and construction of the building or extension, and the services, fittings and equipment provided in or in connection with the building or extension which will assist the responsible person to operate and maintain the building or extension with reasonable safety;
(b) a “relevant building” is a building to which the Regulatory Reform (Fire Safety) Order 2005 applies, or will apply after the completion of building work;
(c) a “relevant change of use” is a material change of use where, after the change of use takes place, the Regulatory Reform (Fire Safety) Order 2005 will apply, or continue to apply, to the building; and
(d) “responsible person” has the meaning given by article 3 of the Regulatory Reform (Fire Safety) Order 2005.
The aim of this regulation is to ensure that the person responsible for the building has sufficient
information relating to fire safety to enable them to manage the building effectively. The aim of
regulation 38 will be achieved when the person responsible for the building has all the information
to enable them to do all of the following.
a. Understand and implement the fire safety strategy of the building.
b. Maintain any fire safety system provided in the building.
c. Carry out an effective fire risk assessment of the building.
BS 7974 and supporting published documents (PDs) provide a framework for and guidance on the application of fire safety engineering principles to the design of buildings.
The Building Regulations do not impose any requirements on the management of a building, but do assume that it will be properly managed. This includes, for example, keeping protected escape routes virtually ‘fire sterile’.
Appropriate fire safety design considers the way in which a building will be managed. Any reliance on an unrealistic or unsustainable management regime cannot be considered to have met the requirements of the regulations.
Once the building is in use, the management regime should be maintained and a suitable risk assessment undertaken for any variation in that regime. Failure to take proper management responsibility may result in the prosecution of an employer, building owner or occupier under legislation such as the Regulatory Reform (Fire Safety) Order 2005.
The fire safety aspects of the Building Regulations aim to achieve reasonable standards of health and safety for people in and around buildings. People, regardless of ability, age or gender, should be able to access buildings and use their facilities. The fire safety measures incorporated into a building should take account of the needs of everyone who may access the building, both as visitors and as people who live or work in it. It is not appropriate, except in exceptional circumstances, to assume that certain groups of people will be excluded from a building because of its use. The provisions in this approved document are considered to be of a reasonable standard for most buildings. However, some people’s specific needs might not be addressed. In some situations, additional measures may be needed to accommodate these needs. This should be done on a case- by-case basis.
The fire safety requirements of the Building Regulations will probably be satisfied by following the relevant guidance in this approved document. However, approved documents provide guidance for some common building situations, and there may be alternative methods of complying with the Building Regulation requirements. If alternative methods are adopted, the overall level of safety should not be lower than the approved document provides. It is the responsibility of those undertaking the work to demonstrate compliance. If other standards or guidance documents are adopted, the relevant fire safety recommendations in those publications should be followed in their entirety. However, in some circumstances it may be necessary to use one publication to supplement another. Care must be taken when using supplementary guidance to ensure that an integrated approach is used in any one building. Guidance documents intended specifically for assessing fire safety in existing buildings often include less onerous provisions than those for new buildings and are therefore unlikely to be appropriate for building work that is controlled by the Building Regulations. Buildings for industrial and commercial activities that present a special fire hazard, e.g. those that sell fuels, may require additional fire precautions to those in this approved document.
Details should be provided of all of the following.
a. Specifications of fire safety equipment provided, including routine maintenance schedules.
b. Any assumptions regarding the management of the building in the design of the fire safety arrangements.
c. Any provision enabling the evacuation of disabled people, which can be used when designing personal emergency evacuation plans.
The records should include details of all of the following.
b. All assumptions in the design of the fire safety arrangements for the management of the building.
building safety manager
The aim of this regulation is to ensure that the person responsible for the building has sufficient
information relating to fire safety to enable them to manage the building effectively. The aim of
regulation 38 will be achieved when the person responsible for the building has all the information
to enable them to do all of the following.
a. Understand and implement the fire safety strategy of the building.
b. Maintain any fire safety system provided in the building.
c. Carry out an effective fire risk assessment of the building.
The Building Regulations do not impose any requirements on the management of a building, but do assume that it will be properly managed. This includes, for example, keeping protected escape routes virtually ‘fire sterile’.
Appropriate fire safety design considers the way in which a building will be managed. Any reliance on an unrealistic or unsustainable management regime cannot be considered to have met the requirements of the regulations.
Once the building is in use, the management regime should be maintained and a suitable risk assessment undertaken for any variation in that regime. Failure to take proper management responsibility may result in the prosecution of an employer, building owner or occupier under legislation such as the Regulatory Reform (Fire Safety) Order 2005.
Details should be provided of all of the following.
a. Specifications of fire safety equipment provided, including routine maintenance schedules.
b. Any assumptions regarding the management of the building in the design of the fire safety arrangements.
c. Any provision enabling the evacuation of disabled people, which can be used when designing personal emergency evacuation plans.
The records should include details of all of the following. d. All passive fire safety measures, including all of the following. e. All of the following.
a. The fire safety strategy, including all assumptions in the design of the fire safety systems (such as fire load). Any risk assessments or risk analysis.
b. All assumptions in the design of the fire safety arrangements for the management of the building.
c. All of the following.
i. Escape routes (including occupant load and capacity of escape routes).
ii. Any provision to enable the evacuation of disabled people.
iii. Escape strategy (e.g. simultaneous or phased).
iv. Muster points.
i. Compartmentation (i.e. location of fire-separating elements).
ii. Cavity barriers.
iii. Fire doorsets, including fire doorsets fitted with a self-closing device and other doors equipped with relevant hardware (e.g. electronic security locks).
iv. Duct dampers.
v. Fire shutters.
i. Fire detector heads.
ii. Smoke detector heads.
iii. Alarm call points.
iv. Detection/alarm control boxes.
v. Alarm sounders.
vi. Emergency communications systems.
vii. CCTV.
viii. Fire safety signage.
ix. Emergency lighting.
x. Fire extinguishers.
xi. Dry or wet fire mains and other firefighting equipment.
xii. Other interior facilities for the fire and rescue service.
xiii. Emergency control rooms.
xiv. Location of hydrants outside the building.
xv. Other exterior facilities for the fire and rescue service.
f. All active fire safety measures, including both of the following.
i. Sprinkler system(s) design, including isolating valves and control equipment.
ii. Smoke control system(s) (or heating, ventilation and air conditioning system with a smoke control function) design, including mode of operation and control systems.
g. Any high risk areas (e.g. heating machinery) and particular hazards.
h. Plans of the building as built, showing the locations of the above.
i. Both of the following.
i. Specifications of any fire safety equipment provided, including all of the following.
• Operational details.
• Operators’ manuals.
• Software.
• System zoning.
• Routine inspection, testing and maintenance schedules.
ii. Records of any acceptance or commissioning tests.
j. Any other details appropriate for the specific building.
The records should include details of all of the following.
b. All assumptions in the design of the fire safety arrangements for the management of the building.
building services designer
Fire safety information 38.
(1) This regulation applies where building work—
(a) consists of or includes the erection or extension of a relevant building; or
(b) is carried out in connection with a relevant change of use of a building, and Part B of Schedule 1 imposes a requirement in relation to the work.
(2) The person carrying out the work shall give fire safety information to the responsible person not later than the date of completion of the work, or the date of occupation of the building or extension, whichever is the earlier.
(3) In this regulation—
(a) “fire safety information” means information relating to the design and construction of the building or extension, and the services, fittings and equipment provided in or in connection with the building or extension which will assist the responsible person to operate and maintain the building or extension with reasonable safety;
(b) a “relevant building” is a building to which the Regulatory Reform (Fire Safety) Order 2005 applies, or will apply after the completion of building work;
(c) a “relevant change of use” is a material change of use where, after the change of use takes place, the Regulatory Reform (Fire Safety) Order 2005 will apply, or continue to apply, to the building; and
(d) “responsible person” has the meaning given by article 3 of the Regulatory Reform (Fire Safety) Order 2005.
building work
Fire safety information 38.
(1) This regulation applies where building work—
(a) consists of or includes the erection or extension of a relevant building; or
(b) is carried out in connection with a relevant change of use of a building, and Part B of Schedule 1 imposes a requirement in relation to the work.
(2) The person carrying out the work shall give fire safety information to the responsible person not later than the date of completion of the work, or the date of occupation of the building or extension, whichever is the earlier.
(3) In this regulation—
(a) “fire safety information” means information relating to the design and construction of the building or extension, and the services, fittings and equipment provided in or in connection with the building or extension which will assist the responsible person to operate and maintain the building or extension with reasonable safety;
(b) a “relevant building” is a building to which the Regulatory Reform (Fire Safety) Order 2005 applies, or will apply after the completion of building work;
(c) a “relevant change of use” is a material change of use where, after the change of use takes place, the Regulatory Reform (Fire Safety) Order 2005 will apply, or continue to apply, to the building; and
(d) “responsible person” has the meaning given by article 3 of the Regulatory Reform (Fire Safety) Order 2005.
capacity
In every case measure the volume contained by all of the following.
a. Under surface of roof.
b. Upper surface of lowest floor.
c. Inner surface of enclosing walls.
When there is not an outer enclosingwall, measure to the outermost edge of the floor slab.
The measured volume should include internal walls and partitions.
a. Cubic capacity of a building Internal wall or partition
b. Cubic capacity of compartments or separated part of a building
Diagram D2 Cubic capacity
see Table B4
See Table C1
See Appendix C
NOTES:
1. BS EN 13501-2 Classification using data from fire resistance tests, excluding ventilation services.BS EN 13501-3
Classification using data from fire resistance tests on products and elements used in building service installations: fire resisting ducts and fire dampers. BS EN 13501-4 Classification using data from fire resistance tests on components of smoke control systems.
In the European classification:
‘R’ is the resistance to fire in terms of loadbearing capacity.
‘E’ is the resistance to fire in terms of integrity.
‘I’ is the resistance to fire in terms of insulation.
The national classifications do not automatically equate with the alternative classifications in the European column, therefore products cannot typically assume a European class unless they have been tested accordingly.
2. BS 476-20 for general principles,BS 476-21 for loadbearing elements,BS 476-22 for non-loadbearing elements,BS 476-23 for fire-protecting suspended ceilings and BS 476-24 for ventilation ducts.
3. Applies to loadbearing elements only (see paragraph B19).
4. Guidance on increasing the fire resistance of existing timber floors is given in BRE Digest 208.
5. Only if a suspended ceiling meets the appropriate provisions should it be relied on to add to the fire resistance of the floor.
6. Such walls may contain areas that do not need to be fire resisting (unprotected areas). See Section 11.
7. Unless needed as part of a wall in item 5a or 5b.
8. Except for any limitations on uninsulated glazed elements given in Table B5.
NOTES:
Separation distances do not apply to the boundary between roofs of a pair of semi-detached dwellinghouses and to enclosed/covered walkways. However, see Diagram 5.2 if the roof passes over the top of a compartment wall.
Polycarbonate and uPVC rooflights that achieve a class C-s3, d2 rating by test may be regarded as having a BROOF(t4) designation.
1. The designation of external roof surfaces is explained in Appendix B.
2. Not acceptable on any of the following buildings.
a. Dwellinghouses in terraces of three or more dwellinghouses.
b. Any other buildings with a cubic capacity of more than 1500m3.
3. Acceptable on buildings not listed in (1) if both of the following apply.
a. Part of the roof has a maximum area of 3m2 and is a minimum of 1500mm from any similar part.
b. The roof between the parts is covered with a material rated class A2-s3, d2 or better.
NOTES:
1. Fire appliances are not standardised. The building control body may, in consultation with the local fire and rescue service, use other dimensions.
2. The road base can be designed to 12.5 tonne capacity. Structures such as bridges should have the full 17-tonne capacity. The weight of high reach appliances is distributed over a number of axles, so infrequent use of a route designed to accommodate 12.5 tonnes should not cause damage.
The alternative source of water supply should be one of the following, subject to consultation with the local fire and rescue service.
a. A charged static water tank with a minimum capacity of 45,000 litres.
b. A spring, river, canal or pond that is capable of fulfilling both of the following conditions.
i. Providing or storing a minimum of 45,000 litres of water at all times.
ii. Providing access, space and a hardstanding for a pumping appliance.
c. Any other water supply that the local fire and rescue service considers appropriate.
Basic information on the location of fire protection measures may be sufficient. An as-built plan of the building should be provided showing all of the following.
a. Escape routes – this should include exit capacity (i.e. the maximum allowable number of people for each storey and for the building).
b. Location of fire-separating elements (including cavity barriers in walk-in spaces).
c. Fire doorsets, fire doorsets fitted with a self-closing device and other doors equipped with relevant hardware.
d. Locations of fire and/or smoke detector heads, alarm call points, detection/alarm control boxes, alarm sounders, fire safety signage, emergency lighting, fire extinguishers, dry or wet fire mains and other firefighting equipment, and hydrants outside the building.
e. Any sprinkler systems, including isolating valves and control equipment.
f. Any smoke control systems, or ventilation systems with a smoke control function, including mode of operation and control systems.
g. Any high risk areas (e.g. heating machinery).
The records should include details of all of the following.
c. All of the following.
i. Escape routes (including occupant load and capacity of escape routes).
ii. Any provision to enable the evacuation of disabled people.
iii. Escape strategy (e.g. simultaneous or phased).
iv. Muster points.
Common to all of the provisions of Part B of the Building Regulations is the property of fire
resistance. Fire resistance is a measure of one or more of the following.
a. Resistance to collapse (loadbearing capacity), which applies to loadbearing elements only,
denoted R in the European classification of the resistance to fire performance.
b. Resistance to fire penetration (integrity), denoted E in the European classification of the
resistance to fire performance.
c. Resistance to the transfer of excessive heat (insulation), denoted I in the European
classification of the resistance to fire performance.
For non-residential sprinkler systems designed and installed to BS EN 12845, water supplies should
consist of either of the following.
a. Two single water supplies complying with clause 9.6.1, independent of each other.
b. Two stored water supplies meeting all of the following conditions.
i. Gravity or suction tanks should satisfy all the requirements of clause 9.6.2(b), other than
capacity.
ii. Any pump arrangements should comply with clause 10.2.
iii. In addition to meeting the requirements for inflow, either of the following should apply.
• The capacity of each tank should be at least half the specified minimum water volume
of a single full capacity tank, appropriate to the hazard.
• One tank should be at least equivalent to half the specified water volume of a single
full capacity tank, and the other shall not be less than the minimum volume of a
reduced capacity tank (see clause 9.3.4) appropriate to the hazard.
The total capacity of the water supply in (iii), including any inflow for a reduced capacity
tank, should be at least that of a single full holding capacity tank that complies with
cavity
The external wall of a building should not provide a medium for fire spread if that is likely to be a risk to health and safety. Combustible materials and cavities in external walls and attachments to them can present such a risk, particularly in tall buildings. The guidance in this section is designed to reduce the risk of fire spread as well as the risk of ignition from flames coming from adjacent buildings.
Cavity barriers should be provided in accordance with Section 5 in dwellinghouses and Section 8 in flats.
The external envelope of a building should not provide a medium for fire spread if it is likely to be a risk to health or safety. The use of combustible materials for cladding framework, or of combustible thermal insulation as an overcladding or in ventilated cavities, may present such a risk in tall buildings, even though the provisions for external surfaces in Diagram 40 may have been satisfied.
In a building with a storey 18m or more above ground level, insulation material used in ventilated cavities in the external wall construction should be of limited combustibility (see Appendix A). This restriction does not apply to masonry cavity wall construction which complies with Diagram 32 in Section 10. Advice on the use of thermal insulation material is given in the BRE Report Fire performance of external thermal insulation for walls of multi-storey buildings (BR 135, 1988).
If windows are replaced, it may be necessary to provide cavity barriers around the opening in accordance with Section 5.
See para 2.5
Alternative cavity barrier arrangements in roof space over protected stairway in a house with a storey more than 4.5m above ground level
Cavities in the construction of a building provide a ready route for the spread of smoke and flame, which can present a greater danger as any spread is concealed. For the purpose of this document, a cavity is considered to be any concealed space.
To reduce the potential for fire spread, cavity barriers should be provided for both of the following.
a. To divide cavities.
b. To close the edges of cavities.
Cavity barriers should not be confused with fire-stopping details (Section 9).
Cavity barriers should be provided at all of the following locations.
a. At the edges of cavities, including around openings (such as windows, doors and exit/entry points for services).
b. At the junction between an external cavity wall and every compartment floor and compartment wall.
c. At the junction between an internal cavity wall and every compartment floor, compartment wall or other wall or door assembly forming a fire resisting barrier.
This does not apply where a wall meets the conditions of Diagram 5.3.
It is not appropriate to complete a line of compartment walls by fitting cavity barriers above them. The compartment wall should be extended to the underside of the floor or roof above.
Cavity barriers, tested from each side separately, should provide a minimum of both of the following:
a. 30 minutes’ integrity (E 30)
b. 15 minutes’ insulation (I 15).
They may be formed by a construction provided for another purpose if it achieves the same performance.
Cavity barriers in a stud wall or partition, or provided around openings, may be formed of any of the following.
a. Steel, a minimum of 0.5mm thick.
b. Timber, a minimum of 38mm thick.
c. Polythene-sleeved mineral wool, or mineral wool slab, under compression when installed in the cavity.
d. Calcium silicate, cement-based or gypsum-based boards, a minimum of 12mm thick.
These do not necessarily achieve the performance specified in paragraph 5.20.
NOTE: Cavity barriers provided around openings may be formed by the window or door frame, if the frame is constructed of steel or timber of the minimum thickness in (a) or (b), as appropriate.
Cavity barriers should be tightly fitted to a rigid construction and mechanically fixed in position. If this is not possible (e.g. where a cavity barrier joins to slates, tiles, corrugated sheeting or similar materials) the junction should be fire-stopped.
Cavity barriers should be fixed so their performance is unlikely to be made ineffective by any of the following.
a. Movement of the building due to subsidence, shrinkage or temperature change, and movement of the external envelope due to wind.
b. During a fire, collapse of services penetrating the cavity barriers, either by the failure of the supporting system or through degradation of the service itself (e.g. by melting or burning).
c. During a fire, failure of the cavity barrier fixings. (In roof spaces, where cavity barriers are fixed to roof members, there is no expectation of fire resistance from roof members provided for the purpose of support.)
d. During a fire, failure of any material or construction to which cavity barriers abut. (For example, a suspended ceiling that continues over a fire resisting wall or partition collapses, and the cavity barrier fails prematurely because the ceiling was not designed to provide a minimum fire resistance of EI 30.)
Openings should be limited to the following.
a. Fire doorsets with a minimum E 30 rating, fitted in accordance with Appendix C.
b. The passage of pipes that follow the provisions in Section 9.
c. The passage of cables or conduits containing one or more cables.
d. Openings fitted with a suitably mounted and appropriate fire damper.
e. Ducts that are either of the following.
i. Fire resisting (minimum E 30).
ii. Fitted with a suitably mounted and appropriate fire damper where they pass through the cavity barrier.
NOTE: For further guidance on openings in cavity barriers see Section 9.
NOTES:
1. Materials used to close the cavity in this arrangement do not need to achieve a specific performance in relation to fire resistance.
2. Domestic meter cupboards may be installed provided that the following conditions are met:
a. There are no more than two cupboards per dwelling
b. The openings in the outer wall leaf are not bigger than 800X500mm for each cupboard
c. The inner leaf is not penetrated except by a sleeve not more than 80X80mm, which is fire-stopped.
3. Materials achieving class B-s3, d2 or worse may be placed within the cavity.
See para 5.18
Cavities in the construction of a building provide a ready route for the spread of smoke and flame, which can present a greater danger as any spread is concealed. For the purpose of this document, a cavity is considered to be any concealed space.
Fire-stopping (same resistance as compartment)
Cavity barriers
NOTE:
1. See paragraph 8.5
See para 8.2
To reduce the potential for fire spread, cavity barriers should be provided for both of the following.
a. To divide cavities.
b. To close the edges of cavities.
See Diagram 8.1. Cavity barriers should not be confused with fire-stopping details (Section 9).
NOTES:
1. Materials used to close the cavity in this arrangement do not need to achieve a specific performance in relation to fire resistance.
2. Domestic meter cupboards may be installed provided that the following conditions are met:
a. There are no more than two cupboards per dwelling
b. The openings in the outer wall leaf are not bigger than 800X500mm for each cupboard
c. The inner leaf is not penetrated except by a sleeve not more than 80X80mm, which is fire-stopped.
3. Materials achieving class B-s3, d2 or worse may be placed within the cavity.
See para 8.3
Cavity barriers should be provided at all of the following locations.
a. At the edges of cavities, including around openings (such as windows, doors and exit/entry points for services).
b. At the junction between an external cavity wall and every compartment floor and compartment wall.
c. At the junction between an internal cavity wall and every compartment floor, compartment wall or other wall or door assembly forming a fire resisting barrier.
This does not apply where a wall meets the conditions of Diagram 8.2.
It is not appropriate to complete a line of compartment walls by fitting cavity barriers above them. The compartment walls should extend to the underside of the floor or roof above.
If the fire resisting construction of a protected escape route is either of the following.
a. Not carried to full storey height.
b. At the top storey, not carried to the underside of the roof covering.
Then the cavity above or below the fire resisting construction should be either of the following.
i. Fitted with cavity barriers on the line of the enclosure.
ii. For cavities above the fire resisting construction, enclosed on the lower side by a fire resisting ceiling (minimum EI 30) that extends throughout the building, compartment or separated part (see Diagram 8.3).
In divided corridors (paragraph 3.25 and following) with cavities, fire-stopping should be provided to prevent alternative escape routes being affected by fire and/or smoke.
Cavity barriers are not required between double-skinned corrugated or profiled insulated roof sheeting, if the sheeting complies with all of the following.
a. The sheeting is rated class A2-s3, d2 or better.
b. Both surfaces of the insulating layer are rated class C-s3, d2 or better.
c. Both surfaces of the insulating layer make contact with the inner and outer skins of cladding (Diagram 8.4).
Cavity barriers, tested from each side separately, should provide a minimum of both of the following:
a. 30 minutes’ integrity (E 30)
b. 15 minutes’ insulation (I 15).
They may be formed by a construction provided for another purpose if it achieves the same performance.
Cavity barriers should meet the requirements set out in paragraphs 5.21 to 5.24.
Provide a proprietary, tested sealing system that will maintain the fire resistance of the wall, floor or cavity barrier.
cavity barrier
The external walls of buildings other than those described in regulation 7(4) of the Building Regulations should achieve either of the following.
a. Follow the provisions given in paragraphs 10.5 to 10.9, which provide guidance on all of the following.
i. External surfaces.
ii. Materials and products.
iii. Cavities and cavity barriers..
b. Meet the performance criteria given in BRE report BR 135 for external walls using full-scale test data from BS 8414-1 or BS 8414-2.
Cavity barriers should be provided in accordance with Section 5 in dwellinghouses and Section 8 in flats.
The combined clear cross-sectional area of all smoke outlets should be a minimum of 1/40 of the area of the floor of the storey they serve.
Basic information on the location of fire protection measures may be sufficient. An as-built plan of the building should be provided showing all of the following.
a. Escape routes – this should include exit capacity (i.e. the maximum allowable number of people for each storey and for the building).
b. Location of fire-separating elements (including cavity barriers in walk-in spaces).
c. Fire doorsets, fire doorsets fitted with a self-closing device and other doors equipped with relevant hardware.
d. Locations of fire and/or smoke detector heads, alarm call points, detection/alarm control boxes, alarm sounders, fire safety signage, emergency lighting, fire extinguishers, dry or wet fire mains and other firefighting equipment, and hydrants outside the building.
e. Any sprinkler systems, including isolating valves and control equipment.
f. Any smoke control systems, or ventilation systems with a smoke control function, including mode of operation and control systems.
g. Any high risk areas (e.g. heating machinery).
The records should include details of all of the following. d. All passive fire safety measures, including all of the following. e. All of the following.
a. The fire safety strategy, including all assumptions in the design of the fire safety systems (such as fire load). Any risk assessments or risk analysis.
b. All assumptions in the design of the fire safety arrangements for the management of the building.
c. All of the following.
i. Escape routes (including occupant load and capacity of escape routes).
ii. Any provision to enable the evacuation of disabled people.
iii. Escape strategy (e.g. simultaneous or phased).
iv. Muster points.
i. Compartmentation (i.e. location of fire-separating elements).
ii. Cavity barriers.
iii. Fire doorsets, including fire doorsets fitted with a self-closing device and other doors equipped with relevant hardware (e.g. electronic security locks).
iv. Duct dampers.
v. Fire shutters.
i. Fire detector heads.
ii. Smoke detector heads.
iii. Alarm call points.
iv. Detection/alarm control boxes.
v. Alarm sounders.
vi. Emergency communications systems.
vii. CCTV.
viii. Fire safety signage.
ix. Emergency lighting.
x. Fire extinguishers.
xi. Dry or wet fire mains and other firefighting equipment.
xii. Other interior facilities for the fire and rescue service.
xiii. Emergency control rooms.
xiv. Location of hydrants outside the building.
xv. Other exterior facilities for the fire and rescue service.
f. All active fire safety measures, including both of the following.
i. Sprinkler system(s) design, including isolating valves and control equipment.
ii. Smoke control system(s) (or heating, ventilation and air conditioning system with a smoke control function) design, including mode of operation and control systems.
g. Any high risk areas (e.g. heating machinery) and particular hazards.
h. Plans of the building as built, showing the locations of the above.
i. Both of the following.
i. Specifications of any fire safety equipment provided, including all of the following.
• Operational details.
• Operators’ manuals.
• Software.
• System zoning.
• Routine inspection, testing and maintenance schedules.
ii. Records of any acceptance or commissioning tests.
j. Any other details appropriate for the specific building.
The records should include details of all of the following.
d. All passive fire safety measures, including all of the following.
i. Compartmentation (i.e. location of fire-separating elements).
ii. Cavity barriers.
iii. Fire doorsets, including fire doorsets fitted with a self-closing device and other doors equipped with relevant hardware (e.g. electronic security locks).
iv. Duct dampers.
v. Fire shutters.
The records should include details of all of the following.
d. All passive fire safety measures, including all of the following.
ii. Cavity barriers.
If windows are replaced, it may be necessary to provide cavity barriers around the opening in accordance with Section 5.
See para 2.5
Alternative cavity barrier arrangements in roof space over protected stairway in a house with a storey more than 4.5m above ground level
See Diagram 2.1c. The dwellinghouse should have either of the following. Cavity barriers or a fire resisting ceiling (minimum EI 30) should be provided above a protected stairway enclosure (Diagram 2.3). b. Alternative escape route – a top storey separated from lower storeys by fire resisting construction (minimum REI 30) and with an alternative escape route leading to its own final exit.
a. Protected stairway – a stair separated by fire resisting construction (minimum REI 30) at all storeys, that complies with one of the following.
i. Extends to a final exit (Diagram 2.2a).
ii. Gives access to a minimum of two ground level final exits that are separated from each other by fire resisting construction (minimum REI 30) and fire doorsets (minimum E 20) (Diagram 2.2b).
Cavities in the construction of a building provide a ready route for the spread of smoke and flame, which can present a greater danger as any spread is concealed. For the purpose of this document, a cavity is considered to be any concealed space.
To reduce the potential for fire spread, cavity barriers should be provided for both of the following.
a. To divide cavities.
b. To close the edges of cavities.
Cavity barriers should not be confused with fire-stopping details (Section 9).
Cavity barriers should be provided at all of the following locations.
a. At the edges of cavities, including around openings (such as windows, doors and exit/entry points for services).
b. At the junction between an external cavity wall and every compartment floor and compartment wall.
c. At the junction between an internal cavity wall and every compartment floor, compartment wall or other wall or door assembly forming a fire resisting barrier.
This does not apply where a wall meets the conditions of Diagram 5.3.
It is not appropriate to complete a line of compartment walls by fitting cavity barriers above them. The compartment wall should be extended to the underside of the floor or roof above.
Cavity barriers, tested from each side separately, should provide a minimum of both of the following:
a. 30 minutes’ integrity (E 30)
b. 15 minutes’ insulation (I 15).
They may be formed by a construction provided for another purpose if it achieves the same performance.
Cavity barriers in a stud wall or partition, or provided around openings, may be formed of any of the following.
a. Steel, a minimum of 0.5mm thick.
b. Timber, a minimum of 38mm thick.
c. Polythene-sleeved mineral wool, or mineral wool slab, under compression when installed in the cavity.
d. Calcium silicate, cement-based or gypsum-based boards, a minimum of 12mm thick.
These do not necessarily achieve the performance specified in paragraph 5.20.
NOTE: Cavity barriers provided around openings may be formed by the window or door frame, if the frame is constructed of steel or timber of the minimum thickness in (a) or (b), as appropriate.
Cavity barriers should be tightly fitted to a rigid construction and mechanically fixed in position. If this is not possible (e.g. where a cavity barrier joins to slates, tiles, corrugated sheeting or similar materials) the junction should be fire-stopped.
Cavity barriers should be fixed so their performance is unlikely to be made ineffective by any of the following.
a. Movement of the building due to subsidence, shrinkage or temperature change, and movement of the external envelope due to wind.
b. During a fire, collapse of services penetrating the cavity barriers, either by the failure of the supporting system or through degradation of the service itself (e.g. by melting or burning).
c. During a fire, failure of the cavity barrier fixings. (In roof spaces, where cavity barriers are fixed to roof members, there is no expectation of fire resistance from roof members provided for the purpose of support.)
d. During a fire, failure of any material or construction to which cavity barriers abut. (For example, a suspended ceiling that continues over a fire resisting wall or partition collapses, and the cavity barrier fails prematurely because the ceiling was not designed to provide a minimum fire resistance of EI 30.)
Openings should be limited to the following.
a. Fire doorsets with a minimum E 30 rating, fitted in accordance with Appendix C.
b. The passage of pipes that follow the provisions in Section 9.
c. The passage of cables or conduits containing one or more cables.
d. Openings fitted with a suitably mounted and appropriate fire damper.
e. Ducts that are either of the following.
i. Fire resisting (minimum E 30).
ii. Fitted with a suitably mounted and appropriate fire damper where they pass through the cavity barrier.
NOTE: For further guidance on openings in cavity barriers see Section 9.
Cavities in the construction of a building provide a ready route for the spread of smoke and flame, which can present a greater danger as any spread is concealed. For the purpose of this document, a cavity is considered to be any concealed space.
Fire-stopping (same resistance as compartment)
Cavity barriers
NOTE:
1. See paragraph 8.5
See para 8.2
To reduce the potential for fire spread, cavity barriers should be provided for both of the following.
a. To divide cavities.
b. To close the edges of cavities.
See Diagram 8.1. Cavity barriers should not be confused with fire-stopping details (Section 9).
Cavity barriers should be provided at all of the following locations.
a. At the edges of cavities, including around openings (such as windows, doors and exit/entry points for services).
b. At the junction between an external cavity wall and every compartment floor and compartment wall.
c. At the junction between an internal cavity wall and every compartment floor, compartment wall or other wall or door assembly forming a fire resisting barrier.
This does not apply where a wall meets the conditions of Diagram 8.2.
It is not appropriate to complete a line of compartment walls by fitting cavity barriers above them. The compartment walls should extend to the underside of the floor or roof above.
If the fire resisting construction of a protected escape route is either of the following.
a. Not carried to full storey height.
b. At the top storey, not carried to the underside of the roof covering.
Then the cavity above or below the fire resisting construction should be either of the following.
i. Fitted with cavity barriers on the line of the enclosure.
ii. For cavities above the fire resisting construction, enclosed on the lower side by a fire resisting ceiling (minimum EI 30) that extends throughout the building, compartment or separated part (see Diagram 8.3).
Cavity barriers are not required between double-skinned corrugated or profiled insulated roof sheeting, if the sheeting complies with all of the following.
a. The sheeting is rated class A2-s3, d2 or better.
b. Both surfaces of the insulating layer are rated class C-s3, d2 or better.
c. Both surfaces of the insulating layer make contact with the inner and outer skins of cladding (Diagram 8.4).
Cavity barriers, tested from each side separately, should provide a minimum of both of the following:
a. 30 minutes’ integrity (E 30)
b. 15 minutes’ insulation (I 15).
They may be formed by a construction provided for another purpose if it achieves the same performance.
Cavity barriers should meet the requirements set out in paragraphs 5.21 to 5.24.
Provide a proprietary, tested sealing system that will maintain the fire resistance of the wall, floor or cavity barrier.
The free area of a smoke ventilator should be measured by either of the following.
a. The declared aerodynamic free area in accordance with BS EN 12101-2.
b. The total unobstructed cross-sectional area (geometric free area), measured in the plane where
the area is at a minimum and at right angles to the direction of air flow (Diagram D7).
cavity stop
External fire spread
B4.(1)The external walls of the building shall adequately resist the spread of fire over the walls and from one building to another, having regard to the height, use and position of the building.
(2)The roof of the building shall adequately resist the spread of fire over the roof and from one building to another, having regard to the use and position of the building.
Regulation 7 – Materials and workmanship
(1)Building work shall be carried out—
(a)with adequate and proper materials which—
(i)are appropriate for the circumstances in which they are used,
(ii)are adequately mixed or prepared, and
(iii)are applied, used or fixed so as adequately to perform the functions for which they are designed; and
(b)in a workmanlike manner.
(2)Subject to paragraph (3), building work shall be carried out so that materials which become part of an external wall, or specified attachment, of a relevant building are of European Classification A2-s1, d0 or A1, classified in accordance with BS EN 13501-1:2007+A1:2009 entitled “Fire classification of construction products and building elements. Classification using test data from reaction to fire tests” (ISBN 978 0 580 59861 6) published by the British Standards Institution on 30th March 2007 and amended in November 2009.
(3)Paragraph (2) does not apply to—
(a)cavity trays when used between two leaves of masonry;
(b)any part of a roof (other than any part of a roof which falls within paragraph (iv) of regulation 2(6))if that part is connected to an external wall;
(c)door frames and doors;
(d)electrical installations;
(e)insulation and water proofing materials used below ground level;
(f)intumescent and fire stopping materials where the inclusion of the materials is necessary to meet the requirements of Part B of Schedule 1;
(g)membranes;
(h)seals, gaskets, fixings, sealants and backer rods;
(i)thermal break materials where the inclusion of the materials is necessary to meet the thermal bridging requirements of Part L of Schedule 1; or
(j)window frames and glass.
(4)In this regulation—
(a)a “relevant building” means a building with a storey (not including roof-top plant areas or any storey consisting exclusively of plant rooms) at least 18 metres above ground level and which—
(i)contains one or more dwellings;
(ii)contains an institution; or
(iii)contains a room for residential purposes(excluding any room in a hostel, hotel or boarding house); and
(b)“above ground level” in relation to a storey means above ground level when measured from the lowest ground level adjoining the outside of a building to the top of the floor surface of the storey.
ce marking
Flats
1. Within the enclosures of a protected entrance hall or protected landing, or within fire resisting separation shown in Section 3, Diagram 3.4.
2. Within either:
a. the enclosures of a protected stairway
b. fire resisting separation shown in Diagram 2.2.
3. Within fire resisting separation either:
a. shown in Diagram 2.4
b. described in paragraph 2.16b.
4. Existing window between an attached/integral garage and the dwellinghouse.
5. Adjacent to an external escape stair (see paragraph 2.17 and Diagram 2.7) or roof escape route (see paragraph 2.13).
6. Between residential/sleeping accommodation and a common escape route (corridor, lobby or stair).
7. Between a protected stairway(1)and either:
a. the accommodation
b. a corridor that is not a protected corridor other than in item 6 above.
8. Between either:
a. a protected stairway(1)and a protected lobby or protected corridor
b. accommodation and a protected lobby other than in item 6 above.
9. Between the accommodation and a protected corridor that forms a dead end,other than in item 6 above.
10.Between accommodation and any other corridor, or sub-dividing corridors,other than in item 6 above.
11. Beside an external escape route.
Table B5
see Table B3
Table B5
12. Beside an external escape stair (see paragraph 3.68 and Diagram 3.11) or roof escape route (see paragraph 3.30).
NOTES:
Items 1 and 8 apply also to single storey buildings.
Fire resisting glass should be marked with the name of the manufacturer and the name of the product.
Further guidance can be found in A Guide to Best Practice in the Specification and Use of Fire-resistant Glazed Systems published by the Glass and Glazing Federation.
1. If the protected stairway is also a protected shaft or a firefighting stair (see Section 15), there may be further
restrictions on the use of glazed elements.
2. Measured vertically from the landing floor level or the stair pitch line.
3. The 100mm limit is intended to reduce the risk of fire spreading from a floor covering.
Every doorway or other exit providing access to a means of escape, other than exits in ordinary use (e.g. main entrances), should be distinctively and conspicuously marked by an exit sign in accordance with BS ISO 3864-1 and BS 5499-4. For this reason, blocks of flats with a single stair in regular use would not usually require any fire exit signage.
Advice on fire safety signs, including emergency escape signs, is given in the HSE publication Safety Signs and Signals: Guidance on Regulations.
Some buildings may require additional signs to comply with other legislation.
For the purposes of requirements B2 and B4, thermoplastic materials should be classified as TP(a)
rigid, TP(a) flexible or TP(b), as follows:
a. TP(a) rigid
i. rigid solid uPVC sheet
ii. solid (as distinct from double- or multi-skinned) polycarbonate sheet a minimum of 3mm
thick
iii. multi-skinned rigid sheet made from uPVC or polycarbonate that has a class 1 rating when
tested to BS 476-7
iv. any other rigid thermoplastic product, a specimen of which (at the thickness of the
product as put on the market), when tested to BS 2782-0 Method 508A, performs so that
both:
• the test flame extinguishes before the first mark
• the duration of flaming or afterglow does not exceed 5 seconds following removal of
the burner.
b. TP(a) flexible
Flexible products a maximum of 1mm thick that comply with the Type C requirements
of BS 5867-2 when tested to BS 5438 Test 2 with the flame applied to the surface of the
specimens for 5, 15, 20 and 30 seconds respectively, but excluding the cleansing procedure; and
c. TP(b)
i. rigid solid polycarbonate sheet products a maximum of 3mm thick, or multi-skinned
polycarbonate sheet products that do not qualify as TP(a) by test
ii. other products which, when a specimen of the material between 1.5 and 3mm thick is
tested in accordance with BS 2782-0 Method 508A, have a maximum rate of burning of
50mm/minute.
NOTE: If it is not possible to cut or machine a 3mm thick specimen from the product, then a 3mm
Except for doorsets listed in paragraph C12, all fire doorsets should be marked with one of the
following fire safety signs, complying with BS 5499-5, as appropriate.
a. To be kept closed when not in use – mark ‘Fire door keep shut’.
b. To be kept locked when not in use – mark ‘Fire door keep locked shut’.
c. Held open by an automatic release mechanism or free swing device – mark ‘Automatic fire door
keep clear’.
All fire doorsets should be marked on both sides, except fire doorsets to cupboards and service
ducts, which should be marked on the outside.
ceiling
see Table B4
See Table C1
See Appendix C
NOTES:
1. BS EN 13501-2 Classification using data from fire resistance tests, excluding ventilation services.BS EN 13501-3
Classification using data from fire resistance tests on products and elements used in building service installations: fire resisting ducts and fire dampers. BS EN 13501-4 Classification using data from fire resistance tests on components of smoke control systems.
In the European classification:
‘R’ is the resistance to fire in terms of loadbearing capacity.
‘E’ is the resistance to fire in terms of integrity.
‘I’ is the resistance to fire in terms of insulation.
The national classifications do not automatically equate with the alternative classifications in the European column, therefore products cannot typically assume a European class unless they have been tested accordingly.
2. BS 476-20 for general principles,BS 476-21 for loadbearing elements,BS 476-22 for non-loadbearing elements,BS 476-23 for fire-protecting suspended ceilings and BS 476-24 for ventilation ducts.
3. Applies to loadbearing elements only (see paragraph B19).
4. Guidance on increasing the fire resistance of existing timber floors is given in BRE Digest 208.
5. Only if a suspended ceiling meets the appropriate provisions should it be relied on to add to the fire resistance of the floor.
6. Such walls may contain areas that do not need to be fire resisting (unprotected areas). See Section 11.
7. Unless needed as part of a wall in item 5a or 5b.
8. Except for any limitations on uninsulated glazed elements given in Table B5.
Smoke outlets should be both of the following.
a. Sited at high level in either the ceiling or wall of the space they serve.
b. Evenly distributed around the perimeter, to discharge to the open air.
A lift well connecting different compartments should form a protected shaft (see Section 7).
The surface linings of walls and ceilings should meet the classifications in Table 4.1.
a. DIFFUSER FORMING PART OF CEILING
b. DIFFUSER IN FITTING BELOW AND NOT FORMING PART OF CEILING
See para 4.15
The following paragraphs apply to lighting diffusers forming part of a ceiling. Diffusers may be part of a luminaire or used below sources of light. The following paragraphs do not apply to diffusers of light fittings attached to the soffit of a ceiling or suspended beneath a ceiling (Diagram 4.1).
Diffusers constructed of thermoplastic material may be incorporated in ceilings to rooms and circulation spaces, but not to protected stairways, if both the following conditions are met.
a. Except for the upper surfaces of the thermoplastic panels, wall and ceiling surfaces exposed in the space above the suspended ceiling should comply with paragraph 4.1.
b. Diffusers should be classified as one of the following.
i. TP(a) rigid – no restrictions on their extent.
ii. TP(b) – limited in their extent (see Table 4.2 and Diagram 4.2).
A ceiling constructed from TP(a) flexible panels should meet the following conditions.
a. Have a maximum area of 5m2.
b. Be supported on all sides.
For the purposes of this requirement, a wall includes both of the following.
a. The internal surface of internal and external glazing (except glazing in doors).
b. Any part of a ceiling which slopes at an angle greater than 70 degrees to the horizontal.
Materials within this zone – at plane of ceiling – should comply with Table 4.1
Rooflights
See Table 4.2
For the purposes of this requirement, a ceiling includes all of the following.
a. Glazed surfaces.
b. Any part of a wall at 70 degrees or less to the horizontal.
c. The underside of a gallery.
d. The underside of a roof exposed to the room below.
For the purposes of this requirement, a ceiling does not include any of the following.
a. Trap doors and their frames.
b. The frames of windows or rooflights and frames in which glazing is fitted.
c. Architraves, cover moulds, picture rails, exposed beams and similar narrow members.
NOTE:
The ceiling should meet the following conditions.
a. Provide a minimum fire resistance of EI 30.
b. Be imperforate, except for an opening described in paragraph 5.24.
c. Extend through out the building or compartment.
d. Not be easily demountable.
See para 8.5
Thermoplastic materials used for window glazing, rooflights and lighting diffusers within suspended ceilings do not need to meet the criteria within paragraph B19 onwards, if the guidance to requirements B2 and B4 is followed.
A thermoplastic material alone when used as a lining to a wall or ceiling cannot be assumed to protect a substrate. The surface rating of both thermoplastic material and substrate must therefore meet the required classification. If, however, the thermoplastic material is fully bonded to a non-thermoplastic substrate, then only the surface rating of the composite needs to meet the required classification.
cellar
A lift shaft serving storeys above ground level should not serve any basement, if either of the following applies.
a. There is only one escape stair serving storeys above ground level and smoke from a basement fire would adversely affect escape routes in the upper storeys.
b. The lift shaft is within the enclosure to an escape stair that terminates at ground level.
Where more than one escape route is available from a storey (or part of a building), then some of the escape routes from that storey or part of the building may be by way of an external stair provided all of the following conditions are met:
a. There is a at least one internal escape stair from every part of each storey (excluding plant areas).
b. The stair serves a floor not more than 6m above either the ground level or a roof podium which is itself served by an independent protected stairway.
c. The stair meets the provisions in paragraph 3.68.
circulation space
Smoke alarms should be provided in the circulation spaces of the dwelling in accordance with paragraphs 1.1 to 1.4.
Lift machine rooms should be sited over the lift well where possible. Where buildings or part of a building with only one stairway make this arrangement impractical, the lift machine room should be sited outside the protected stairway.
Thermoplastic material classified as a TP(a) rigid product may be used to glaze external windows to rooms, but not external windows to circulation spaces. Approved Document K includes guidance on the safety of glazing.
clear access zone
Final exit locations should be clearly visible and recognisable.
clear opening width
Final exit locations should be clearly visible and recognisable.
Doors should be readily openable to avoid undue delay to people escaping. Doors on escape routes (both within and from the building) should comply with paragraphs 3.91 to 3.98. Guidance on door closing and ‘hold open’ devices for fire doorsets is set out in Appendix C.
NOTE: Paragraphs 3.91 to 3.98 do not apply to flat entrance doors.
Guidance on door closing and ‘hold open’ devices for fire doorsets is set out in Appendix C.
All doors on escape routes should be hung to meet both of the following conditions.
a. Open by a minimum of 90 degrees.
b. Open with a swing that complies with both of the following.
i. Is clear of any change of floor level, other than a threshold or single step on the line of the doorway.
ii. Does not reduce the effective width of any escape route across a landing.
Any door opening towards a corridor or a stair should be recessed to prevent its swing encroaching on the effective width.
Doors should contain vision panels in both of the following situations.
a. Where doors on escape routes divide corridors.
b. Where doors are hung to swing both ways.
Approved Document M contains guidance about vision panels in doors across accessible corridors and Approved Document K contains guidance about the safety of glazing.
Where revolving doors, automatic doors and turnstiles are placed across escape routes they should comply with one of the following.
a. They are automatic doors of the required width and comply with one of the following conditions.
i. Their failsafe system provides outward opening from any open position.
ii. They have a monitored failsafe system to open the doors if the mains electricity supply fails.
iii. They failsafe to the open position if the power fails.
b. Non-automatic swing doors of the required width are provided immediately adjacent to the revolving or automatic door or turnstile.
Width is measured according to the following.
a. For a door (or doorway), the clear width when the door is open (Diagram D1).
b. For an escape route, either of the following.
i. When the route is defined by walls: the width at 1500mm above finished floor level.
ii. Elsewhere: the minimum width of passage available between any fixed obstructions.
c. For a stair, the clear width between the walls or balustrades. On escape routes and stairs,
handrails and strings intruding into the width by a maximum of 100mm on each side may be
ignored. Rails used for guiding a stair-lift may be ignored, but it should be possible to park the
lift’s chair or carriage in a position that does not obstruct the stair or landing.
clear width
Effective clear width (door stop to projecting ironmongery)
Effective clear width (door stop to door leaf)
Effective clear width (door stop to projecting ironmongery)
Effective clear width (door stop to door leaf)
Final exit locations should be clearly visible and recognisable.
A stair of acceptable width for everyday use will be sufficient for escape purposes. If it is also a firefighting stair, it should be at least 1100mm wide. The width is the clear width between the walls or balustrades. Any handrails and strings intruding into that width by a maximum of 100mm on each side may be ignored.
Width is measured according to the following.
a. For a door (or doorway), the clear width when the door is open (Diagram D1).
b. For an escape route, either of the following.
i. When the route is defined by walls: the width at 1500mm above finished floor level.
ii. Elsewhere: the minimum width of passage available between any fixed obstructions.
c. For a stair, the clear width between the walls or balustrades. On escape routes and stairs,
handrails and strings intruding into the width by a maximum of 100mm on each side may be
ignored. Rails used for guiding a stair-lift may be ignored, but it should be possible to park the
lift’s chair or carriage in a position that does not obstruct the stair or landing.
closable opening
Doors should be readily openable to avoid undue delay to people escaping. Doors on escape routes (both within and from the building) should comply with paragraphs 3.91 to 3.98. Guidance on door closing and ‘hold open’ devices for fire doorsets is set out in Appendix C.
NOTE: Paragraphs 3.91 to 3.98 do not apply to flat entrance doors.
Guidance on door closing and ‘hold open’ devices for fire doorsets is set out in Appendix C.
Where revolving doors, automatic doors and turnstiles are placed across escape routes they should comply with one of the following.
a. They are automatic doors of the required width and comply with one of the following conditions.
i. Their failsafe system provides outward opening from any open position.
ii. They have a monitored failsafe system to open the doors if the mains electricity supply fails.
iii. They failsafe to the open position if the power fails.
b. Non-automatic swing doors of the required width are provided immediately adjacent to the revolving or automatic door or turnstile.
commissioning
The records should include details of all of the following.
f. All active fire safety measures, including both of the following.
i. Sprinkler system(s) design, including isolating valves and control equipment.
ii. Smoke control system(s) (or heating, ventilation and air conditioning system with a smoke control function) design, including mode of operation and control systems.
The records should include details of all of the following.
i. Both of the following.
i. Specifications of any fire safety equipment provided, including all of the following.
• Operational details.
• Operators’ manuals.
• Software.
• System zoning.
• Routine inspection, testing and maintenance schedules.
ii. Records of any acceptance or commissioning tests.
The records should include details of all of the following.
i. Both of the following.
i. Specifications of any fire safety equipment provided, including all of the following.
• Operational details.
• Operators’ manuals.
• Software.
• System zoning.
• Routine inspection, testing and maintenance schedules.
The records should include details of all of the following.
i. Both of the following.
ii. Records of any acceptance or commissioning tests.
If glazed elements in fire resisting enclosures and doors can only meet the required integrity performance, their use is limited. These limitations depend on whether the enclosure forms part of a protected shaft (see Section 7) and the provisions set out in Appendix B, Table B5. If both integrity and insulation performance can be met, there is no restriction in this document on the use or amount of glass.
Electrically powered locks should return to the unlocked position in all of the following situations.
a. If the fire detection and alarm system operates.
b. If there is loss of power or system error.
c. If the security mechanism override is activated.
Security mechanism overrides for electrically powered locks should be a Type A call point, as described in BS 7273-4. The call point should be positioned on the side approached by people escaping. If the door provides escape in either direction, a call point should be installed on both sides of the door.
Where revolving doors, automatic doors and turnstiles are placed across escape routes they should comply with one of the following.
a. They are automatic doors of the required width and comply with one of the following conditions.
i. Their failsafe system provides outward opening from any open position.
ii. They have a monitored failsafe system to open the doors if the mains electricity supply fails.
iii. They failsafe to the open position if the power fails.
b. Non-automatic swing doors of the required width are provided immediately adjacent to the revolving or automatic door or turnstile.
Non-combustible materials are defined a. (National classes) when tested to BS 476: b. (European classes) when classified as class Table A6 identifies non-combustible products
in Table A6 either as listed products, or in terms
of performance:
Part 4:1970 Non-combustibility test for
materials or Part 11 :1982; or
A 1 in accordance with BS EN 13501-1 :2002
Fire classification of construction products
and building elements. Classification using
data from reaction to fire tests when tested
to BS EN ISO 1182:2002 Reaction to fire tests
for building products - Non-combustibility
test and BS EN ISO 1716:2002 Reaction to
fire tests for building products. Determination
of the gross calorific value.
and materials, and lists circumstances where
their use is necessary.
Materials of limited combustibility are defined in TableA7:
a. (National classes) by reference to the method specified in BS 476: Part 11 :1982; or
b. (European classes) in terms of performance when classified as class A2-s3, d2 in accordance with BS EN 13501-1 :2002, Fire classification of construction products and building elements, Part 1 Classification using data from reaction to fire tests when tested to BS EN ISO 1182:2002, Reaction to fire tests for building products -Non-combustibility test or BS EN ISO 1716:2002 Reaction to fire tests for building products -Determination of the gross calorific value and BS EN 13823:2002, Reaction to fire tests for building products - Building products excluding floorings exposed to the thermal attack by a single burning item.
Table A7 also includes composite products (such as plasterboard) which are considered acceptable, and where these are exposed as linings they should also meet any appropriate flame spread rating.
Materials of limited combustibility are defined in Table A7:
a. (National classes) by reference to the method specified in BS476: Part 11:1982; or
b. (European classes) in terms of performance when classified as class A2-s3, d2 in accordance with BS EN 13501-1 :2002, Fire classification of construction products and building elements, Part 1 - Classification using data from reaction to fire tests when tested to BS EN ISO 1182:2002, Reaction to fire tests for building products - Non combustibility test or BS EN ISO 1716:2002 Reaction to fire tests for building products - Determination of the gross calorific value and BS EN 13823:2002, Reaction to fire tests for building products - Building products excluding floorings exposed to the thermal attack by a single burning item.
Table A7 also includes composite products (such as plasterboard) which are considered acceptable and where these are exposed as linings they should also meet any appropriate flame spread rating.
Under fire conditions, ventilation and air-conditioning systems should be compatible with smoke control systems and need to be considered in their respective design.
Where it is proposed to assess the classification of a product or system in lieu of carrying out a specific test (as in paragraph B1c), this should be done in accordance with the relevant standard for extended application for the test in question and should include details of the test evidence that has been used to support the assessment.
For performance classifications where there is no specific standard for extended
application, assessment reports should be produced in accordance with the principles of BS EN 15725 and should include details of the test evidence that has been used to support the assessment. Further information on best practice is provided in the Passive Fire Protection Forum’s Guide to Undertaking Technical Assessments of the Fire Performance of Construction Products Based on Fire Test Evidence.
NOTE: Regulation 7(2) limits components used in or on the external walls of certain buildings to materials achieving class A2-s1, d0 or class A1 (see Section 12).
Assessments cannot be used to demonstrate compliance with this requirement.
Any test evidence used to verify the fire resistance rating of a doorset or shutter should be
checked to ensure both of the following.
a. It adequately demonstrates compliance.
b. It is applicable to the complete installed assembly. Small differences in detail may significantly
affect the rating.
Until relevant harmonised product standards are published, for the purposes of meeting the
Building Regulations, products tested in accordance with BS EN 1634-1 (with or without pre-fire test
mechanical conditioning) that achieve the minimum performance in Table C1 will be deemed to
satisfy the provisions.
common balcony
For flats more than 4.5m above ground level, a balcony outside an alternative exit should be a common balcony meeting the conditions described in paragraph 3.22.
Any alternative exit from a flat should comply with all of the following.
a. It should be remote from the main entrance door to the flat.
b. It should lead to a final exit, via a common stair if necessary, through one of the following.
i. A door to an access corridor, access lobby or common balcony.
ii. An internal private stair leading to an access corridor, access lobby or common balcony at another level.
iii. A door to a common stair.
iv. A door to an external stair.
v. A door to an escape route over a flat roof.
Any access route leading to a final exit or common stair should comply with the provisions for means of escape in the common parts of a flat (see paragraph 3.25).
In general, doors on escape routes (whether or not the doors are fire doorsets) should be either of the following.
a. Not fitted with a lock, latch or bolt fastenings.
b. Fitted only with simple fastenings that are all of the following.
i. Easy to operate; it should be apparent how to undo the fastening.
ii. Operable from the side approached by people escaping.
iii. Operable without a key.
iv. Operable without requiring people to manipulate more than one mechanism.
Doors may be fitted with hardware to allow them to be locked when rooms are empty.
If a secure door is operated by code or combination keypad, swipe or proximity card, biometric data, etc., a security mechanism override should be possible from the side approached by people escaping.
The door of any doorway or exit should be hung to open in the direction of escape whenever reasonably practicable. It should always be hung to open in the direction of escape if more than 60 people might be expected to use it during a fire.
All doors on escape routes should be hung to meet both of the following conditions.
a. Open by a minimum of 90 degrees.
b. Open with a swing that complies with both of the following.
i. Is clear of any change of floor level, other than a threshold or single step on the line of the doorway.
ii. Does not reduce the effective width of any escape route across a landing.
common parts
Separate guidance applies to means of escape within the flat and within the common parts of the building that lead to a place of safety. Flats at ground level are treated similarly to dwellinghouses. With increasing height, more complex provisions are needed.
In single stair buildings, smoke vents on the storey where the fire is initiated, and the vent at the head of the stair, should be activated by smoke detectors in the common parts.
In buildings with more than one stair, smoke vents may be activated manually. The control system should open the vent at the head of the stair before, or at the same time as, the vent on the storey where the fire is located. Smoke detection is not required for ventilation purposes in this instance.
Except in buildings described in paragraph 3.28, common stairs forming part of the only escape route from a flat should not serve any of the following.
a. Covered car park.
b. Boiler room.
c. Fuel storage space.
d. Other ancillary accommodation of similar fire risk.
Where a common stair is not part of the only escape route from a flat, it may also serve ancillary accommodation from which it is separated by a protected lobby or protected corridor (minimum REI 30).
Common to all of the provisions of Part B of the Building Regulations is the property of fire
resistance. Fire resistance is a measure of one or more of the following.
a. Resistance to collapse (loadbearing capacity), which applies to loadbearing elements only,
denoted R in the European classification of the resistance to fire performance.
b. Resistance to fire penetration (integrity), denoted E in the European classification of the
resistance to fire performance.
c. Resistance to the transfer of excessive heat (insulation), denoted I in the European
classification of the resistance to fire performance.
common stair
Flats
1. Within the enclosures of a protected entrance hall or protected landing, or within fire resisting separation shown in Section 3, Diagram 3.4.
2. Within either:
a. the enclosures of a protected stairway
b. fire resisting separation shown in Diagram 2.2.
3. Within fire resisting separation either:
a. shown in Diagram 2.4
b. described in paragraph 2.16b.
4. Existing window between an attached/integral garage and the dwellinghouse.
5. Adjacent to an external escape stair (see paragraph 2.17 and Diagram 2.7) or roof escape route (see paragraph 2.13).
6. Between residential/sleeping accommodation and a common escape route (corridor, lobby or stair).
7. Between a protected stairway(1)and either:
a. the accommodation
b. a corridor that is not a protected corridor other than in item 6 above.
8. Between either:
a. a protected stairway(1)and a protected lobby or protected corridor
b. accommodation and a protected lobby other than in item 6 above.
9. Between the accommodation and a protected corridor that forms a dead end,other than in item 6 above.
10.Between accommodation and any other corridor, or sub-dividing corridors,other than in item 6 above.
11. Beside an external escape route.
Table B5
see Table B3
Table B5
12. Beside an external escape stair (see paragraph 3.68 and Diagram 3.11) or roof escape route (see paragraph 3.30).
NOTES:
Items 1 and 8 apply also to single storey buildings.
Fire resisting glass should be marked with the name of the manufacturer and the name of the product.
Further guidance can be found in A Guide to Best Practice in the Specification and Use of Fire-resistant Glazed Systems published by the Glass and Glazing Federation.
1. If the protected stairway is also a protected shaft or a firefighting stair (see Section 15), there may be further
restrictions on the use of glazed elements.
2. Measured vertically from the landing floor level or the stair pitch line.
3. The 100mm limit is intended to reduce the risk of fire spreading from a floor covering.
A lift shaft serving storeys above ground level should not serve any basement, if either of the following applies.
a. There is only one escape stair serving storeys above ground level and smoke from a basement fire would adversely affect escape routes in the upper storeys.
b. The lift shaft is within the enclosure to an escape stair that terminates at ground level.
A lift shaft serving storeys above ground level should not serve any basement, if either of the following applies.
a. There is only one escape stair serving storeys above ground level and smoke from a basement fire would adversely affect escape routes in the upper storeys.
b. The lift shaft is within the enclosure to an escape stair that terminates at ground level.
Any alternative exit from a flat should comply with all of the following.
a. It should be remote from the main entrance door to the flat.
b. It should lead to a final exit, via a common stair if necessary, through one of the following.
i. A door to an access corridor, access lobby or common balcony.
ii. An internal private stair leading to an access corridor, access lobby or common balcony at another level.
iii. A door to a common stair.
iv. A door to an external stair.
v. A door to an escape route over a flat roof.
Any access route leading to a final exit or common stair should comply with the provisions for means of escape in the common parts of a flat (see paragraph 3.25).
Any alternative exit from a flat should comply with all of the following.
a. It should be remote from the main entrance door to the flat.
b. It should lead to a final exit, via a common stair if necessary, through one of the following.
i. A door to an access corridor, access lobby or common balcony.
ii. An internal private stair leading to an access corridor, access lobby or common balcony at another level.
iii. A door to a common stair.
iv. A door to an external stair.
v. A door to an escape route over a flat roof.
Any access route leading to a final exit or common stair should comply with the provisions for means of escape in the common parts of a flat (see paragraph 3.25).
From the flat entrance door, a single escape route is acceptable in either of the following cases.
a. The flat is on a storey served by a single common stair and both of the following apply.
i. Every flat is separated from the common stair by a protected lobby or common protected corridor (see Diagram 3.7).
ii. The maximum travel distance in Table 3.1, for escape in one direction only, is not exceeded.
b. The flat is in a dead end of a common corridor served by two (or more) common stairs and the maximum travel distance given in Table 3.1, for escape in one direction only, is not exceeded (Diagram 3.8).
From the flat entrance door, a single escape route is acceptable in either of the following cases.
a. The flat is on a storey served by a single common stair and both of the following apply.
i. Every flat is separated from the common stair by a protected lobby or common protected corridor (see Diagram 3.7).
ii. The maximum travel distance in Table 3.1, for escape in one direction only, is not exceeded.
b. The flat is in a dead end of a common corridor served by two (or more) common stairs and the maximum travel distance given in Table 3.1, for escape in one direction only, is not exceeded (Diagram 3.8).
Despite the provisions described, it is probable that some smoke will get into the common corridor or lobby from a fire in a flat.
There should therefore be some means of ventilating the common corridors/lobbies to control smoke and so protect the common stairs. This means of ventilation offers additional protection to that provided by the fire doors to the stair, as well as some protection to the corridors/lobbies.
Ventilation can be natural (paragraphs 3.50 to 3.53) or mechanical (paragraph 3.54).
Despite the provisions described, it is probable that some smoke will get into the common corridor or lobby from a fire in a flat.
There should therefore be some means of ventilating the common corridors/lobbies to control smoke and so protect the common stairs. This means of ventilation offers additional protection to that provided by the fire doors to the stair, as well as some protection to the corridors/lobbies.
Ventilation can be natural (paragraphs 3.50 to 3.53) or mechanical (paragraph 3.54).
In single stair buildings, smoke vents on the storey where the fire is initiated, and the vent at the head of the stair, should be activated by smoke detectors in the common parts.
In buildings with more than one stair, smoke vents may be activated manually. The control system should open the vent at the head of the stair before, or at the same time as, the vent on the storey where the fire is located. Smoke detection is not required for ventilation purposes in this instance.
In single stair buildings, smoke vents on the storey where the fire is initiated, and the vent at the head of the stair, should be activated by smoke detectors in the common parts.
In buildings with more than one stair, smoke vents may be activated manually. The control system should open the vent at the head of the stair before, or at the same time as, the vent on the storey where the fire is located. Smoke detection is not required for ventilation purposes in this instance.
A building should provide access to more than one common stair if it does not meet the criteria for a single common stair (see paragraph 3.26 and 3.27).
A building should provide access to more than one common stair if it does not meet the criteria for a single common stair (see paragraph 3.26 and 3.27).
Every common stair should be a protected stairway. Where the protected stairway passes from one compartment to another, it should be within a protected shaft.
Every common stair should be a protected stairway. Where the protected stairway passes from one compartment to another, it should be within a protected shaft.
Except in buildings described in paragraph 3.28, common stairs forming part of the only escape route from a flat should not serve any of the following.
a. Covered car park.
b. Boiler room.
c. Fuel storage space.
d. Other ancillary accommodation of similar fire risk.
Except in buildings described in paragraph 3.28, common stairs forming part of the only escape route from a flat should not serve any of the following.
a. Covered car park.
b. Boiler room.
c. Fuel storage space.
d. Other ancillary accommodation of similar fire risk.
Where a common stair is not part of the only escape route from a flat, it may also serve ancillary accommodation from which it is separated by a protected lobby or protected corridor (minimum REI 30).
Where a common stair is not part of the only escape route from a flat, it may also serve ancillary accommodation from which it is separated by a protected lobby or protected corridor (minimum REI 30).
The flights and landings of escape stairs should be constructed of materials achieving class A2-s3, d2 or better in all of the following situations.
a. If the escape stair is the only stair in a building with more than three storeys.
b. If the escape stair is within a basement storey.
c. If the escape stair serves any storey that has a floor level more than 18m above ground or access level.
d. If the escape stair is an external escape stair, except where the stair connects the ground storey or ground level with a floor or flat roof a maximum of 6m above or below ground level.
e. If the escape stair is a firefighting stair.
Materials achieving class B-s3, d2 or worse may be added to the top horizontal surface, except on firefighting stairs.
The flights and landings of escape stairs should be constructed of materials achieving class A2-s3, d2 or better in all of the following situations.
a. If the escape stair is the only stair in a building with more than three storeys.
b. If the escape stair is within a basement storey.
c. If the escape stair serves any storey that has a floor level more than 18m above ground or access level.
d. If the escape stair is an external escape stair, except where the stair connects the ground storey or ground level with a floor or flat roof a maximum of 6m above or below ground level.
e. If the escape stair is a firefighting stair.
Materials achieving class B-s3, d2 or worse may be added to the top horizontal surface, except on firefighting stairs.
Further guidance on the construction of firefighting stairs is given in Section 15 (see also paragraph 3.60). Dimensional constraints on the design of stairs are given in Approved Document K.
Helical stairs and spiral stairs may form part of an escape route provided they are designed in accordance with BS 5395-2. If they are intended to serve members of the public, stairs should be type E (public) stairs.
Helical stairs and spiral stairs may form part of an escape route provided they are designed in accordance with BS 5395-2. If they are intended to serve members of the public, stairs should be type E (public) stairs.
a. SMALL SINGLE STAIR BUILDING
*If smoke control is provided in the lobby, the travel distance can be increased to 7.5m maximum(see Diagram 3.7, example b).
b. SMALL SINGLE STAIR BUILDING WITH NO MORE THAN TWO FLATS PER STOREY
The door between stair and lobby should be free from security fastenings.
If the flats have protected entrance halls, the lobby between the common stair and flat entrance is not essential.
NOTES:
1. The arrangements shown also apply to the top storey.
2. If the travel distance across the lobby in diagram (a) exceeds 4.5m, Diagram 3.7 applies.
3. Where,in Diagram (b), the lobby between the common stair and the dwelling is omitted in smal lsingle stair buildings, an automatic opening vent with a free area of at least 1m2 is required at the top of the stair,which is operated automatically on detection of smoke at any storey in the stair.
4. For further guidance on the fire rating of the fire doorsets from the corridor to the flat and/or stairway refer to Appendix C, Table C1.
Fire resisting construction
Openable vent at high level for fire service use (1.0m2 minimum free area); see paragraph 3.28eSee para 3.28
Diagram 3.9
a. SMALL SINGLE STAIR BUILDING
*If smoke control is provided in the lobby, the travel distance can be increased to 7.5m maximum(see Diagram 3.7, example b).
b. SMALL SINGLE STAIR BUILDING WITH NO MORE THAN TWO FLATS PER STOREY
The door between stair and lobby should be free from security fastenings.
If the flats have protected entrance halls, the lobby between the common stair and flat entrance is not essential.
NOTES:
1. The arrangements shown also apply to the top storey.
2. If the travel distance across the lobby in diagram (a) exceeds 4.5m, Diagram 3.7 applies.
3. Where,in Diagram (b), the lobby between the common stair and the dwelling is omitted in smal lsingle stair buildings, an automatic opening vent with a free area of at least 1m2 is required at the top of the stair,which is operated automatically on detection of smoke at any storey in the stair.
4. For further guidance on the fire rating of the fire doorsets from the corridor to the flat and/or stairway refer to Appendix C, Table C1.
Fire resisting construction
Openable vent at high level for fire service use (1.0m2 minimum free area); see paragraph 3.28eSee para 3.28
Diagram 3.9
Blocks of flats with a top storey more than 11m above ground level (see Diagram D6) should be fitted with a sprinkler system throughout the building in accordance with Appendix E.
NOTE: Sprinklers should be provided within the individual flats, they do not need to be provided in the common areas such as stairs, corridors or landings when these areas are fire sterile.
Blocks of flats with a top storey more than 11m above ground level (see Diagram D6) should be fitted with a sprinkler system throughout the building in accordance with Appendix E.
NOTE: Sprinklers should be provided within the individual flats, they do not need to be provided in the common areas such as stairs, corridors or landings when these areas are fire sterile.
compartment (fire)
Lift machine rooms should be sited over the lift well where possible. Where buildings or part of a building with only one stairway make this arrangement impractical, the lift machine room should be sited outside the protected stairway.
To reduce the risk of fire spreading over the roof from one compartment to another, a 1500mm wide zone of the roof, either side of the wall, should have a covering classified as BROOF(t4), on a substrate or deck of a material rated class A2-s3, d2 or better, as set out in Diagram 5.2a.
Thermoplastic rooflights that, because of paragraph 12.7, are regarded as having a BROOF(t4) classification are not suitable for use in that zone.
All of the following should be provided as compartment walls and compartment floors and should have, as a minimum, the fire resistance given in Appendix B, Table B3.
a. Any floor (unless it is within a flat, i.e. between one storey and another within one individual dwelling).
b. Any wall separating a flat from another part of the building.
c. Any wall enclosing a refuse storage chamber.
d. Any wall common to two or more buildings.
At the junction with another compartment wall or an external wall, the fire resistance of the compartmentation should be maintained. Fire-stopping that meets the provisions in paragraphs 9.24 to 9.29 should be provided.
At the junction of a compartment floor and an external wall with no fire resistance, the external wall should be restrained at floor level. The restraint should reduce movement of the wall away from the floor if exposed to fire.
Compartment walls should be able to accommodate deflection of the floor, when exposed to fire, by either of the following means.
a. Between the wall and floor, provide a head detail that is capable of maintaining its integrity while deforming.
b. Design the wall so it maintains its integrity by resisting the additional vertical load from the floor above.
Where compartment walls are located within the middle half of a floor between vertical supports, the deflection may be assumed to be 40mm unless a smaller value can be justified by assessment. Outside this area, the limit can be reduced linearly to zero at the supports.
For steel beams that do not have the required fire resistance, reference should be made to SCI Publication P288.
Stairs and service shafts connecting compartments should be protected to restrict the spread of fire between the compartments. These are called protected shafts. Walls or floors surrounding a protected shaft are considered to be compartment walls or compartment floors.
Where services could provide a source of ignition, the risk of fire developing and spreading into adjacent compartments should be controlled.
The wall of a flue, duct containing flues or appliance ventilation duct(s) should have a fire resistance (REI) that is at least half of any compartment wall or compartment floor it passes through or is built into (Diagram 9.5).
a. Flue passing through compartment wall or floor
b. Flue built into compartment wall
Flue walls should have a fire resistance of at least one half of that required for the compartment wall or floor and be of class A1construction.
In each case flue walls should have a fire resistance of at least one half of that required for the compartment wall and be of class A1 construction.
See para 9.23
compartment wall
NOTES:
For single storey buildings, the periods under the heading ‘Up to 5’ apply. If single storey buildings have basements, for the basement storeys the period appropriate to their depth applies.
* For the floor over a basement or, if there is more than one basement, the floor over the topmost basement, the higher of the period for the basement storey and the period for the ground or upper storey applies.
† For compartment walls that separate buildings, the period is increased to a minimum of 60 minutes.
+ For any floor that does not contribute to the support of the building within a flat of more than one storey, the period is reduced to 30 minutes.
§ For flat conversions, refer to paragraphs 6.5 to 6.7 regarding the acceptability of 30 minutes.
‡ For elements that do not form part of the structural frame, the period is reduced to 90 minutes.
# For elements that protect the means of escape, the period is increased to 30 minutes.
1. Refer to note 1, Table B3 for the specific provisions of test.
2. Blocks of flats with a floor more than 30m above ground level should be fitted with a sprinkler system in accordance with Appendix E.
NOTE:
Sprinklers only need to be provided within the individual flats, they are not required in the common areas such as stairs, corridors or landings when these areas are fire sterile.
3.‘With sprinkler system’ means that the building is fitted throughout with an automatic sprinkler system in accordance with Appendix E.
4. Very large (over 18m in height or with a 10m deep basement) or unusual dwellinghouses are outside the scope of the guidance provided with regard to dwellinghouses.
5. A minimum of 30 minutes in the case of three storey dwellinghouses, increased to 60 minutes minimum for compartment walls separating buildings.
6. Buildings within the ‘office’, ‘shop and commercial’, ‘assembly and recreation’, ‘industrial’ and ‘storage and other non-residential’ (except car parks for light vehicles) purpose groups (purpose groups 3 to 7(a)) require sprinklers where there is a top storey above 30m.
The sprinkler system should be provided in accordance with Appendix E.
7. The car park should comply with the relevant provisions in the guidance on requirement B3, Section 11 of
Approved Document B Volume 2.
8. For the purposes of meeting the Building Regulations, the following types of steel elements are deemed to have satisfied the minimum period of fire resistance of 15 minutes when tested to the European test method.
i. Beams supporting concrete floors, maximum Hp/A=230m-1 operating under full design load.
ii. Free-standing columns, maximum Hp/A=180m-1 operating under full design load.
iii. Wind bracing and struts, maximum Hp/A=210m-1 operating under full design load.
Guidance is also available in BS EN 1993-1-2.
Common corridors should be protected corridors. The wall between each flat and the corridor should be a compartment wall (minimum REI 30 where the top storey is up to 5m above ground level, otherwise REI 60).
A compartment wall should achieve both of the following.
a. Meet the underside of the roof covering or deck, with fire-stopping to maintain the continuity of fire resistance.
b. Be continued across any eaves.
To reduce the risk of fire spreading over the roof from one compartment to another, a 1500mm wide zone of the roof, either side of the wall, should have a covering classified as BROOF(t4), on a substrate or deck of a material rated class A2-s3, d2 or better, as set out in Diagram 5.2a.
Thermoplastic rooflights that, because of paragraph 12.7, are regarded as having a BROOF(t4) classification are not suitable for use in that zone.
Materials achieving class B-s3, d2 or worse used as a substrate to the roof covering and any timber tiling battens, fully bedded in mortar or other suitable material for the width of the wall (Diagram 5.2b), may extend over the compartment wall in buildings that are a maximum of 15m high.
As an alternative to the provisions of paragraphs 5.12 to 5.14, the compartment wall may extend through the roof for a minimum of either of the following (see Diagram 5.2c).
a. Where the height difference between the two roofs is less than 375mm, 375mm above the top surface of the adjoining roof covering.
b. 200mm above the top surface of the adjoining roof covering where either of the following applies.
i. The height difference between the two roofs is 375mm or more.
ii. The roof coverings either side of the wall are of a material classified as BROOF(t4).
Cavity barriers should be provided at all of the following locations.
a. At the edges of cavities, including around openings (such as windows, doors and exit/entry points for services).
b. At the junction between an external cavity wall and every compartment floor and compartment wall.
c. At the junction between an internal cavity wall and every compartment floor, compartment wall or other wall or door assembly forming a fire resisting barrier.
This does not apply where a wall meets the conditions of Diagram 5.3.
It is not appropriate to complete a line of compartment walls by fitting cavity barriers above them. The compartment wall should be extended to the underside of the floor or roof above.
All compartment walls and compartment floors should achieve both of the following.
a. Form a complete barrier to fire between the compartments they separate.
b. Have the appropriate fire resistance, as given in Appendix B, Table B3 and Table B4.
Timber beams, joists, purlins and rafters may be built into or carried through a masonry or concrete compartment wall if the openings for them are both of the following.
a. As small as practicable.
b. Fire-stopped.
If trussed rafters bridge the wall, failure of the truss due to a fire in one compartment should not cause failure of the truss in another compartment.
The diagram shows three common examples which illustrate the principles. The elements enclosing the shaft (unless formed by adjacent external walls) are compartment walls and floors.
The shaft structure (including any openings) should meet the relevant provisions for: compartment walls (see paragraphs 7.5 to7.19), external walls (see sections 10 and 11 and Diagram 3.10).
See para 7.23
All of the following should be provided as compartment walls and compartment floors and should have, as a minimum, the fire resistance given in Appendix B, Table B3.
a. Any floor (unless it is within a flat, i.e. between one storey and another within one individual dwelling).
b. Any wall separating a flat from another part of the building.
c. Any wall enclosing a refuse storage chamber.
d. Any wall common to two or more buildings.
Compartment walls not described in paragraphs 7.8 and 7.9 should run the full height of the storey in which they are situated.
Compartment walls in a top storey beneath a roof should be continued through the roof space.
At the junction with another compartment wall or an external wall, the fire resistance of the compartmentation should be maintained. Fire-stopping that meets the provisions in paragraphs 9.24 to 9.29 should be provided.
At the junction of a compartment floor and an external wall with no fire resistance, the external wall should be restrained at floor level. The restraint should reduce movement of the wall away from the floor if exposed to fire.
Compartment walls should be able to accommodate deflection of the floor, when exposed to fire, by either of the following means.
a. Between the wall and floor, provide a head detail that is capable of maintaining its integrity while deforming.
b. Design the wall so it maintains its integrity by resisting the additional vertical load from the floor above.
Where compartment walls are located within the middle half of a floor between vertical supports, the deflection may be assumed to be 40mm unless a smaller value can be justified by assessment. Outside this area, the limit can be reduced linearly to zero at the supports.
For steel beams that do not have the required fire resistance, reference should be made to SCI Publication P288.
Materials achieving class B-s3, d2 or worse used as a substrate to the roof covering and any timber tiling battens, fully bedded in mortar or other suitable material for the width of the wall (Diagram 5.2b), may extend over the compartment wall in buildings that are both of the following.
a. A maximum of 15m high.
b. In one of the following purpose groups.
i. All residential purpose groups (purpose groups 1 and 2) other than ‘residential (institutional)’ (purpose group 2(a)).
ii. ‘Office’ (purpose group 3).
iii. ‘Assembly and recreation’ (purpose group 5).
As an alternative to the provisions of paragraph 7.16 or 7.17, the compartment wall may extend through the roof for a minimum of either of the following (see Diagram 5.2c).
a. Where the height difference between the two roofs is less than 375mm, 375mm above the top surface of the adjoining roof covering.
b. 200mm above the top surface of the adjoining roof covering where either of the following applies.
i. The height difference between the two roofs is 375mm or more.
ii. The roof coverings either side of the wall are of a material classified as BROOF(t4).
Openings in a compartment wall common to two or more buildings should be limited to those for either of the following.
a. A fire doorset providing a means of escape, which has the same fire resistance as the wall and is fitted in accordance with the provisions in Appendix C.
b. The passage of a pipe that complies with the provisions in Section 9.
Parts of a building occupied mainly for different purposes should be separated from one another by compartment walls and/or compartment floors. Compartmentation is not needed if one of the different purposes is ancillary to the other. See paragraphs 0.18 and 0.19.
All compartment walls and compartment floors should achieve both of the following.
a. Form a complete barrier to fire between the compartments they separate.
b. Have the appropriate fire resistance, as given in Appendix B, Tables B3 and B4.
Timber beams, joists, purlins and rafters may be built into or carried through a masonry or concrete compartment wall if the openings for them are both of the following.
a. As small as practicable.
b. Fire-stopped.
If trussed rafters bridge the wall, failure of the truss due to a fire in one compartment should not cause failure of the truss in another compartment.
Compartment walls forming a separated part of a building should run the full height of the building in a continuous vertical plane.
Separated parts can be assessed independently to determine the appropriate standard of fire resistance in each. The two separated parts can have different standards of fire resistance.
Cavity barriers should be provided at all of the following locations.
a. At the edges of cavities, including around openings (such as windows, doors and exit/entry points for services).
b. At the junction between an external cavity wall and every compartment floor and compartment wall.
c. At the junction between an internal cavity wall and every compartment floor, compartment wall or other wall or door assembly forming a fire resisting barrier.
This does not apply where a wall meets the conditions of Diagram 8.2.
The insulation should make contact with both skins of sheeting. See also Diagram 5.2a regarding the need for fire-stopping where such roofs pass over the top of a compartment wall.
See para 8.7
It is not appropriate to complete a line of compartment walls by fitting cavity barriers above them. The compartment walls should extend to the underside of the floor or roof above.
a. Flue passing through compartment wall or floor
b. Flue built into compartment wall
Flue walls should have a fire resistance of at least one half of that required for the compartment wall or floor and be of class A1construction.
In each case flue walls should have a fire resistance of at least one half of that required for the compartment wall and be of class A1 construction.
See para 9.23
Fire doorsets often do not provide any significant insulation. Unless providing both integrity
and insulation in accordance with Appendix B, Table B3, a maximum of 25% of the length of a
compartment wall should consist of door openings.
Where it is practicable to maintain a clear space on both sides of the doorway, the above
percentage may be greater.
compartment wall or floor
Cavity barriers should be provided at all of the following locations.
a. At the edges of cavities, including around openings (such as windows, doors and exit/entry points for services).
b. At the junction between an external cavity wall and every compartment floor and compartment wall.
c. At the junction between an internal cavity wall and every compartment floor, compartment wall or other wall or door assembly forming a fire resisting barrier.
This does not apply where a wall meets the conditions of Diagram 5.3.
Cavity barriers should be provided at all of the following locations.
a. At the edges of cavities, including around openings (such as windows, doors and exit/entry points for services).
b. At the junction between an external cavity wall and every compartment floor and compartment wall.
c. At the junction between an internal cavity wall and every compartment floor, compartment wall or other wall or door assembly forming a fire resisting barrier.
This does not apply where a wall meets the conditions of Diagram 5.3.
All compartment walls and compartment floors should achieve both of the following.
a. Form a complete barrier to fire between the compartments they separate.
b. Have the appropriate fire resistance, as given in Appendix B, Table B3 and Table B4.
All compartment walls and compartment floors should achieve both of the following.
a. Form a complete barrier to fire between the compartments they separate.
b. Have the appropriate fire resistance, as given in Appendix B, Table B3 and Table B4.
All of the following should be provided as compartment walls and compartment floors and should have, as a minimum, the fire resistance given in Appendix B, Table B3.
a. Any floor (unless it is within a flat, i.e. between one storey and another within one individual dwelling).
b. Any wall separating a flat from another part of the building.
c. Any wall enclosing a refuse storage chamber.
d. Any wall common to two or more buildings.
All of the following should be provided as compartment walls and compartment floors and should have, as a minimum, the fire resistance given in Appendix B, Table B3.
a. Any floor (unless it is within a flat, i.e. between one storey and another within one individual dwelling).
b. Any wall separating a flat from another part of the building.
c. Any wall enclosing a refuse storage chamber.
d. Any wall common to two or more buildings.
At the junction of a compartment floor and an external wall with no fire resistance, the external wall should be restrained at floor level. The restraint should reduce movement of the wall away from the floor if exposed to fire.
At the junction of a compartment floor and an external wall with no fire resistance, the external wall should be restrained at floor level. The restraint should reduce movement of the wall away from the floor if exposed to fire.
Compartment walls should be able to accommodate deflection of the floor, when exposed to fire, by either of the following means.
a. Between the wall and floor, provide a head detail that is capable of maintaining its integrity while deforming.
b. Design the wall so it maintains its integrity by resisting the additional vertical load from the floor above.
Where compartment walls are located within the middle half of a floor between vertical supports, the deflection may be assumed to be 40mm unless a smaller value can be justified by assessment. Outside this area, the limit can be reduced linearly to zero at the supports.
For steel beams that do not have the required fire resistance, reference should be made to SCI Publication P288.
Compartment walls should be able to accommodate deflection of the floor, when exposed to fire, by either of the following means.
a. Between the wall and floor, provide a head detail that is capable of maintaining its integrity while deforming.
b. Design the wall so it maintains its integrity by resisting the additional vertical load from the floor above.
Where compartment walls are located within the middle half of a floor between vertical supports, the deflection may be assumed to be 40mm unless a smaller value can be justified by assessment. Outside this area, the limit can be reduced linearly to zero at the supports.
For steel beams that do not have the required fire resistance, reference should be made to SCI Publication P288.
Parts of a building occupied mainly for different purposes should be separated from one another by compartment walls and/or compartment floors. Compartmentation is not needed if one of the different purposes is ancillary to the other. See paragraphs 0.18 and 0.19.
Parts of a building occupied mainly for different purposes should be separated from one another by compartment walls and/or compartment floors. Compartmentation is not needed if one of the different purposes is ancillary to the other. See paragraphs 0.18 and 0.19.
All compartment walls and compartment floors should achieve both of the following.
a. Form a complete barrier to fire between the compartments they separate.
b. Have the appropriate fire resistance, as given in Appendix B, Tables B3 and B4.
All compartment walls and compartment floors should achieve both of the following.
a. Form a complete barrier to fire between the compartments they separate.
b. Have the appropriate fire resistance, as given in Appendix B, Tables B3 and B4.
Cavity barriers should be provided at all of the following locations.
a. At the edges of cavities, including around openings (such as windows, doors and exit/entry points for services).
b. At the junction between an external cavity wall and every compartment floor and compartment wall.
c. At the junction between an internal cavity wall and every compartment floor, compartment wall or other wall or door assembly forming a fire resisting barrier.
This does not apply where a wall meets the conditions of Diagram 8.2.
Cavity barriers should be provided at all of the following locations.
a. At the edges of cavities, including around openings (such as windows, doors and exit/entry points for services).
b. At the junction between an external cavity wall and every compartment floor and compartment wall.
c. At the junction between an internal cavity wall and every compartment floor, compartment wall or other wall or door assembly forming a fire resisting barrier.
This does not apply where a wall meets the conditions of Diagram 8.2.
The wall of a flue, duct containing flues or appliance ventilation duct(s) should have a fire resistance (REI) that is at least half of any compartment wall or compartment floor it passes through or is built into (Diagram 9.5).
The wall of a flue, duct containing flues or appliance ventilation duct(s) should have a fire resistance (REI) that is at least half of any compartment wall or compartment floor it passes through or is built into (Diagram 9.5).
a. Flue passing through compartment wall or floor
b. Flue built into compartment wall
Flue walls should have a fire resistance of at least one half of that required for the compartment wall or floor and be of class A1construction.
In each case flue walls should have a fire resistance of at least one half of that required for the compartment wall and be of class A1 construction.
See para 9.23
a. Flue passing through compartment wall or floor
b. Flue built into compartment wall
Flue walls should have a fire resistance of at least one half of that required for the compartment wall or floor and be of class A1construction.
In each case flue walls should have a fire resistance of at least one half of that required for the compartment wall and be of class A1 construction.
See para 9.23
compartmentation
In the Secretary of State’s view, requirement B3 is met by achieving all of the following.
a. For defined periods, loadbearing elements of structure withstand the effects of fire without
loss of stability.
b. Compartmentation of buildings by fire resisting construction elements.
c. Automatic fire suppression is provided where it is necessary.
d. Protection of openings in fire-separating elements to maintain continuity of the fire separation.
e. Inhibition of the unseen spread of fire and smoke in cavities, in order to reduce the risk of
structural failure and spread of fire and smoke, where they pose a threat to the safety of people
in and around the building.
The extent to which any of these measures are necessary is dependent on the use of the building
and, in some cases, its size, and on the location of the elements of construction.
Each flat in a block should have alarms as set out in paragraphs 1.1 to 1.4. With effective compartmentation, a communal fire alarm system is not normally needed. In some buildings, detectors in common parts of the building may need to operate smoke control or other fire protection systems but do not usually sound an audible warning.
In student residences that are designed and occupied as a block of flats, separate automatic detection should be provided in each self-contained flat where all of the following apply.
a. A group of up to six students shares the flat.
b. Each flat has its own entrance door.
c. The compartmentation principles for flats in Section 7 have been followed.
Where a total evacuation strategy is adopted, the alarm system should follow the guidance for buildings other than dwellings in Volume 2 of Approved Document B.
The following assumptions enable a reasonable standard of resistance to the spread of fire to be specified.
a. The size of a fire depends on the compartmentation within the building. A fire may involve a complete compartment, but will not spread to other compartments.
b. The intensity of a fire is related to the building use, but can be moderated by a sprinkler system.
c. Fires in ‘residential’ and ‘assembly and recreation’ buildings (purpose groups 1, 2 and 5) represent a greater risk to life.
d. A building on the far side of the relevant boundary meets both of the following conditions.
i. Has a similar elevation to the one in question.
ii. Is the same distance as the one in question from the common boundary.
e. The radiated heat passing through any part of the fire resisting external wall may be discounted.
Firefighting stairs and firefighting lifts should be approached from either of the following.
a. A firefighting lobby.
b. A protected corridor or protected lobby that complies with the following guidance.
i. Means of escape (Section 3).
ii. Compartmentation (Section 7).
Both the stair and lobby of the firefighting shaft should be provided with a means of venting smoke and heat (see clause 27.1 of BS 9999).
Only services associated with the firefighting shaft, such as ventilation systems and lighting for the firefighting shafts, should pass through or be contained within the firefighting shaft.
Doors of a firefighting lift landing should be a maximum of 7.5m from the door to the firefighting stair (Diagram 15.1).
The records should include details of all of the following.
d. All passive fire safety measures, including all of the following.
i. Compartmentation (i.e. location of fire-separating elements).
ii. Cavity barriers.
iii. Fire doorsets, including fire doorsets fitted with a self-closing device and other doors equipped with relevant hardware (e.g. electronic security locks).
iv. Duct dampers.
v. Fire shutters.
The records should include details of all of the following.
d. All passive fire safety measures, including all of the following.
i. Compartmentation (i.e. location of fire-separating elements).
The provisions in this section make the following assumptions.
a. Any fire is likely to be in a flat.
b. There is no reliance on external rescue.
c. Simultaneous evacuation of all flats is unlikely to be necessary due to compartmentation.
d. Fires in common parts of the building should not spread beyond the fabric in the immediate vicinity. In some cases, however, communal facilities exist that require additional measures to be taken.
The following are excluded from the definition of ‘element of structure’.
a. A structure that supports only a roof, unless either of the following applies.
i. The roof performs the function of a floor, such as a roof terrace, or as a means of escape.
ii. The structure is essential for the stability of an external wall that needs to be fire resisting (e.g. to achieve compartmentation or for the purposes of preventing fire spread between buildings).
b. The lowest floor of the building.
c. External walls, such as curtain walls or other forms of cladding, which transmit only self weight and wind loads and do not transmit floor load.
NOTE: In some cases, structural members within a roof may be essential for the structural stability system of the building. In these cases, the structural members in the roof do not just support a roof and must demonstrate the relevant fire resistance for the building as required by paragraph 5.2 above.
The following are excluded from the definition of ‘element of structure’.
a. A structure that supports only a roof, unless either of the following applies.
i. The roof performs the function of a floor, such as for parking vehicles, or as a means of escape.
ii. The structure is essential for the stability of an external wall that needs to be fire resisting (e.g. to achieve compartmentation or for the purposes of preventing fire spread between buildings).
b. The lowest floor of the building.
c. A platform floor.
d. External walls, such as curtain walls or other forms of cladding, which transmit only self weight and wind loads and do not transmit floor load.
NOTE: In some cases, structural members within a roof may be essential for the structural stability system of the building. In these cases, the structural members in the roof do not just support a roof and must demonstrate the relevant fire resistance for the building as required by the note to paragraph 6.1 above.
At the junction with another compartment wall or an external wall, the fire resistance of the compartmentation should be maintained. Fire-stopping that meets the provisions in paragraphs 9.24 to 9.29 should be provided.
Parts of a building occupied mainly for different purposes should be separated from one another by compartment walls and/or compartment floors. Compartmentation is not needed if one of the different purposes is ancillary to the other. See paragraphs 0.18 and 0.19.
construction
B3.(1) The building shall be designed and constructed so that, in the event of fire, its stability will be maintained for a reasonable period
(2) A wall common to two or more buildings shall be designed and constructed so that it adequately resists the spread of fire between those buildings.
For the purposes of this sub-paragraph a house in a terrace and a semi-detached house are each to be treated as a separate building.
(3) Where reasonably necessary to inhibit the spread of fire within the building, measures shall be taken, to an extent appropriate to the size and intended use of the building, comprising either or both of the following—
(a) sub-division of the building with fire-resisting construction;
(b) installation of suitable automatic fire suppression systems.
(4) The building shall be designed and constructed so that the unseen spread of fire and smoke within concealed spaces in its structure and fabric is inhibited.
Requirement B3(3) does not apply to material alterations to any prison provided under section 33 of the Prison Act 1952.
In the Secretary of State’s view, requirement B3 is met by achieving all of the following.
a. For defined periods, loadbearing elements of structure withstand the effects of fire without
loss of stability.
b. Compartmentation of buildings by fire resisting construction elements.
c. Automatic fire suppression is provided where it is necessary.
d. Protection of openings in fire-separating elements to maintain continuity of the fire separation.
e. Inhibition of the unseen spread of fire and smoke in cavities, in order to reduce the risk of
structural failure and spread of fire and smoke, where they pose a threat to the safety of people
in and around the building.
The extent to which any of these measures are necessary is dependent on the use of the building
and, in some cases, its size, and on the location of the elements of construction.
The external envelope of a building should not contribute to undue fire spread from one part of a
building to another part. This intention can be met by constructing external walls so that both of
the following are satisfied.
a. The risk of ignition by an external source to the outside surface of the building and spread of
fire over the outside surface is restricted.
b. The materials used to construct external walls, and attachments to them, and how they are
assembled do not contribute to the rate of fire spread up the outside of the building.
The extent to which this is necessary depends on the height and use of the building.
Guidance on the design and construction of fire mains is given in BS 9990.
Any external escape stair should meet all of the following conditions (Diagram 2.7).
a. Doors to the stair should be fire resisting (minimum E 30), except for a single exit door from the building to the top landing of a downward-leading external stair.
b. Fire resisting construction (minimum RE 30) is required for the building envelope within the following zones, measured from the flights and landings of the external stair.
i. 1800mm horizontally.
ii. 9m vertically below.
iii. 1100mm above the top landing of the stair (except where the stair leads from basement to ground level).
c. Fire resisting construction (minimum RE 30) should be provided for any part of the building (including doors) within 1800mm of the escape route from the foot of the stair to a place of safety. This does not apply if there are alternative escape routes from the foot of the external escape stair.
d. Stairs more than 6m in height should be protected from adverse weather. Protection should prevent the build-up of snow or ice but does not require full enclosure.
e. Glazing in areas of fire resisting construction should be fixed shut and fire resisting (in terms of integrity, but not insulation) (minimum E 30).
See Diagram 2.1c. The dwellinghouse should have either of the following. Cavity barriers or a fire resisting ceiling (minimum EI 30) should be provided above a protected stairway enclosure (Diagram 2.3). b. Alternative escape route – a top storey separated from lower storeys by fire resisting construction (minimum REI 30) and with an alternative escape route leading to its own final exit.
a. Protected stairway – a stair separated by fire resisting construction (minimum REI 30) at all storeys, that complies with one of the following.
i. Extends to a final exit (Diagram 2.2a).
ii. Gives access to a minimum of two ground level final exits that are separated from each other by fire resisting construction (minimum REI 30) and fire doorsets (minimum E 20) (Diagram 2.2b).
Any external escape stair should meet all of the following conditions (Diagram 3.11).
a. Doors to the stair should be fire resisting (minimum E 30) and be fitted with a self-closing device, except for a single exit door from the building to the top landing of a downward-leading external stair, provided it is the only door onto the landing.
b. Fire resisting construction (minimum RE 30) is required for the building envelope within the following zones, measured from the flights and landings of the external stair.
i. 1800mm above and horizontally.
ii. 9m vertically below.
iii. 1100mm above the top landing of the stair (except where the stair leads from basement to ground level).
c. Fire resisting construction (minimum RE 30) should be provided for any part of the building (including doors) within 1800mm of the escape route from the foot of the stair to a place of safety. This does not apply if there are alternative escape routes from the foot of the external escape stair.
d. Glazing in areas of fire resisting construction should be fixed shut and fire resisting (in terms of integrity but not insulation) (minimum E 30).
e. Stairs more than 6m in height above ground level (e.g. where they are provided above a podium) should be protected from adverse weather. Protection should prevent the build-up of snow or ice but does not require full enclosure.
If the fire resisting construction of a protected escape route is either of the following.
a. Not carried to full storey height.
b. At the top storey, not carried to the underside of the roof covering.
Then the cavity above or below the fire resisting construction should be either of the following.
i. Fitted with cavity barriers on the line of the enclosure.
ii. For cavities above the fire resisting construction, enclosed on the lower side by a fire resisting ceiling (minimum EI 30) that extends throughout the building, compartment or separated part (see Diagram 8.3).
construction lead
See Diagram 2.1c. The dwellinghouse should have either of the following. Cavity barriers or a fire resisting ceiling (minimum EI 30) should be provided above a protected stairway enclosure (Diagram 2.3). b. Alternative escape route – a top storey separated from lower storeys by fire resisting construction (minimum REI 30) and with an alternative escape route leading to its own final exit.
a. Protected stairway – a stair separated by fire resisting construction (minimum REI 30) at all storeys, that complies with one of the following.
i. Extends to a final exit (Diagram 2.2a).
ii. Gives access to a minimum of two ground level final exits that are separated from each other by fire resisting construction (minimum REI 30) and fire doorsets (minimum E 20) (Diagram 2.2b).
The construction separating two adjacent protected stairways (or exit passageways leading to different final exits) should be imperforate.
construction operative
Fire safety information 38.
(1) This regulation applies where building work—
(a) consists of or includes the erection or extension of a relevant building; or
(b) is carried out in connection with a relevant change of use of a building, and Part B of Schedule 1 imposes a requirement in relation to the work.
(2) The person carrying out the work shall give fire safety information to the responsible person not later than the date of completion of the work, or the date of occupation of the building or extension, whichever is the earlier.
(3) In this regulation—
(a) “fire safety information” means information relating to the design and construction of the building or extension, and the services, fittings and equipment provided in or in connection with the building or extension which will assist the responsible person to operate and maintain the building or extension with reasonable safety;
(b) a “relevant building” is a building to which the Regulatory Reform (Fire Safety) Order 2005 applies, or will apply after the completion of building work;
(c) a “relevant change of use” is a material change of use where, after the change of use takes place, the Regulatory Reform (Fire Safety) Order 2005 will apply, or continue to apply, to the building; and
(d) “responsible person” has the meaning given by article 3 of the Regulatory Reform (Fire Safety) Order 2005.
construction site
Refuse storage chambers, refuse chutes and refuse hoppers should be sited and constructed in accordance with BS 5906.
construction specification
Recommendations for the specification, design, construction, installation and maintenance of fire
doorsets constructed with non-metallic door leaves are given in BS 8214.
Guidance on timber fire resisting doorsets, in relation to the new European test standard, may be
found in Timber Fire Resisting Doorsets: Maintaining Performance Under the New European Test
Standard published by the Timber Research and Development Association (TRADA).
Guidance for metal doors is given in Code of Practice for Fire Resisting Metal Doorsets published by
the Door and Shutter Manufacturers’ Association (DSMA).
construction work
Regulations 5(k) and 6(3) provide that, where the use of a building is changed such that the building becomes a building described in regulation 7(4), the construction of the external walls, and specified attachments, must be investigated and, where necessary, work must be carried out to ensure they only contain materials achieving class A2-s1, d0 or class A1, other than those exempted by regulation 7(3).
continuous operation
Fire safety information 38.
(1) This regulation applies where building work—
(a) consists of or includes the erection or extension of a relevant building; or
(b) is carried out in connection with a relevant change of use of a building, and Part B of Schedule 1 imposes a requirement in relation to the work.
(2) The person carrying out the work shall give fire safety information to the responsible person not later than the date of completion of the work, or the date of occupation of the building or extension, whichever is the earlier.
(3) In this regulation—
(a) “fire safety information” means information relating to the design and construction of the building or extension, and the services, fittings and equipment provided in or in connection with the building or extension which will assist the responsible person to operate and maintain the building or extension with reasonable safety;
(b) a “relevant building” is a building to which the Regulatory Reform (Fire Safety) Order 2005 applies, or will apply after the completion of building work;
(c) a “relevant change of use” is a material change of use where, after the change of use takes place, the Regulatory Reform (Fire Safety) Order 2005 will apply, or continue to apply, to the building; and
(d) “responsible person” has the meaning given by article 3 of the Regulatory Reform (Fire Safety) Order 2005.
Where a stair serves an enclosed car park or place of special fire hazard, the lobby or corridor should have a minimum 0.4m2 of permanent ventilation or be protected from the ingress of smoke by a mechanical smoke control system.
NOTE: For refuse chutes and storage see paragraphs 3.55 to 3.58.
In general, doors on escape routes (whether or not the doors are fire doorsets) should be either of the following.
a. Not fitted with a lock, latch or bolt fastenings.
b. Fitted only with simple fastenings that are all of the following.
i. Easy to operate; it should be apparent how to undo the fastening.
ii. Operable from the side approached by people escaping.
iii. Operable without a key.
iv. Operable without requiring people to manipulate more than one mechanism.
Doors may be fitted with hardware to allow them to be locked when rooms are empty.
If a secure door is operated by code or combination keypad, swipe or proximity card, biometric data, etc., a security mechanism override should be possible from the side approached by people escaping.
contrast visually
Electrically powered locks should return to the unlocked position in all of the following situations.
a. If the fire detection and alarm system operates.
b. If there is loss of power or system error.
c. If the security mechanism override is activated.
Security mechanism overrides for electrically powered locks should be a Type A call point, as described in BS 7273-4. The call point should be positioned on the side approached by people escaping. If the door provides escape in either direction, a call point should be installed on both sides of the door.
corridor access
Any alternative exit from a flat should comply with all of the following.
a. It should be remote from the main entrance door to the flat.
b. It should lead to a final exit, via a common stair if necessary, through one of the following.
i. A door to an access corridor, access lobby or common balcony.
ii. An internal private stair leading to an access corridor, access lobby or common balcony at another level.
iii. A door to a common stair.
iv. A door to an external stair.
v. A door to an escape route over a flat roof.
Any access route leading to a final exit or common stair should comply with the provisions for means of escape in the common parts of a flat (see paragraph 3.25).
a. CORRIDOR ACCESS WITHOUT DEAD ENDS
b. CORRIDOR ACCESS WITH DEAD ENDS
The central door may be omitted if maximum travel distance is not more than 15m.
1. The arrangements shown also apply to the top storey.
2. For further guidance on the fire rating of the fire doorsets from the corridor to the flat and/or stairway refer to Appendix C ,Table C1.
Fire doorset provided in accordance with paragraphs 3.50 to 3.53(An external wall vent or smoke shaft located anywhere in the shaded area)
See paras 3.27 and 3.36
dead end
Flats
1. Within the enclosures of a protected entrance hall or protected landing, or within fire resisting separation shown in Section 3, Diagram 3.4.
2. Within either:
a. the enclosures of a protected stairway
b. fire resisting separation shown in Diagram 2.2.
3. Within fire resisting separation either:
a. shown in Diagram 2.4
b. described in paragraph 2.16b.
4. Existing window between an attached/integral garage and the dwellinghouse.
5. Adjacent to an external escape stair (see paragraph 2.17 and Diagram 2.7) or roof escape route (see paragraph 2.13).
6. Between residential/sleeping accommodation and a common escape route (corridor, lobby or stair).
7. Between a protected stairway(1)and either:
a. the accommodation
b. a corridor that is not a protected corridor other than in item 6 above.
8. Between either:
a. a protected stairway(1)and a protected lobby or protected corridor
b. accommodation and a protected lobby other than in item 6 above.
9. Between the accommodation and a protected corridor that forms a dead end,other than in item 6 above.
10.Between accommodation and any other corridor, or sub-dividing corridors,other than in item 6 above.
11. Beside an external escape route.
Table B5
see Table B3
Table B5
12. Beside an external escape stair (see paragraph 3.68 and Diagram 3.11) or roof escape route (see paragraph 3.30).
NOTES:
Items 1 and 8 apply also to single storey buildings.
Fire resisting glass should be marked with the name of the manufacturer and the name of the product.
Further guidance can be found in A Guide to Best Practice in the Specification and Use of Fire-resistant Glazed Systems published by the Glass and Glazing Federation.
1. If the protected stairway is also a protected shaft or a firefighting stair (see Section 15), there may be further
restrictions on the use of glazed elements.
2. Measured vertically from the landing floor level or the stair pitch line.
3. The 100mm limit is intended to reduce the risk of fire spreading from a floor covering.
From the flat entrance door, a single escape route is acceptable in either of the following cases.
a. The flat is on a storey served by a single common stair and both of the following apply.
i. Every flat is separated from the common stair by a protected lobby or common protected corridor (see Diagram 3.7).
ii. The maximum travel distance in Table 3.1, for escape in one direction only, is not exceeded.
b. The flat is in a dead end of a common corridor served by two (or more) common stairs and the maximum travel distance given in Table 3.1, for escape in one direction only, is not exceeded (Diagram 3.8).
a. CORRIDOR ACCESS WITHOUT DEAD ENDS
b. CORRIDOR ACCESS WITH DEAD ENDS
The central door may be omitted if maximum travel distance is not more than 15m.
1. The arrangements shown also apply to the top storey.
2. For further guidance on the fire rating of the fire doorsets from the corridor to the flat and/or stairway refer to Appendix C ,Table C1.
Fire doorset provided in accordance with paragraphs 3.50 to 3.53(An external wall vent or smoke shaft located anywhere in the shaded area)
See paras 3.27 and 3.36
The door of any doorway or exit should be hung to open in the direction of escape whenever reasonably practicable. It should always be hung to open in the direction of escape if more than 60 people might be expected to use it during a fire.
definition
NOTES:
1.In assembly buildings (purpose group 5), a gallery is included as a storey, but not if it is a loading gallery, fly gallery, stage grid, lighting bridge, or any gallery provided for similar purposes, or for maintenance and repair.
2.In other purpose group buildings, galleries are not counted as a storey.
3.For the definition of basement, see Appendix A.
Regulation 7(2) applies to any building with a storey at least 18m above ground level (as
measured in accordance with Diagram D6 in Appendix D) and which contains one or more
dwellings; an institution; or a room for residential purposes. It requires that all materials which become part of an external wall or specified attachment achieve class A2-s1, d0 or class A1 in accordance with BS EN 13501-1, other than those exempted by regulation 7(3).
NOTE: The above includes student accommodation, care homes, sheltered housing, hospitals, dormitories in boarding schools, hotels, hostels and boarding houses. See regulation 7(4) for the definition of relevant buildings.
NOTE: Transposition to national class (Table B1) does not apply to the classification in this paragraph.
External walls and specified attachments are defined in regulation 2(6) and these definitions
include any parts of the external wall as well as balconies, solar panels and solar shading.
See para 2.6
Example of alternative exit in para 2.6(a) (see definition in Appendix A)
The following are excluded from the definition of ‘element of structure’.
a. A structure that supports only a roof, unless either of the following applies.
i. The roof performs the function of a floor, such as a roof terrace, or as a means of escape.
ii. The structure is essential for the stability of an external wall that needs to be fire resisting (e.g. to achieve compartmentation or for the purposes of preventing fire spread between buildings).
b. The lowest floor of the building.
c. External walls, such as curtain walls or other forms of cladding, which transmit only self weight and wind loads and do not transmit floor load.
NOTE: In some cases, structural members within a roof may be essential for the structural stability system of the building. In these cases, the structural members in the roof do not just support a roof and must demonstrate the relevant fire resistance for the building as required by paragraph 5.2 above.
The following are excluded from the definition of ‘element of structure’.
a. A structure that supports only a roof, unless either of the following applies.
i. The roof performs the function of a floor, such as for parking vehicles, or as a means of escape.
ii. The structure is essential for the stability of an external wall that needs to be fire resisting (e.g. to achieve compartmentation or for the purposes of preventing fire spread between buildings).
b. The lowest floor of the building.
c. A platform floor.
d. External walls, such as curtain walls or other forms of cladding, which transmit only self weight and wind loads and do not transmit floor load.
NOTE: In some cases, structural members within a roof may be essential for the structural stability system of the building. In these cases, the structural members in the roof do not just support a roof and must demonstrate the relevant fire resistance for the building as required by the note to paragraph 6.1 above.
definitions
External walls and specified attachments are defined in regulation 2(6) and these definitions
include any parts of the external wall as well as balconies, solar panels and solar shading.
See para 2.6
Example of alternative exit in para 2.6(a) (see definition in Appendix A)
The following are excluded from the definition of ‘element of structure’.
a. A structure that supports only a roof, unless either of the following applies.
i. The roof performs the function of a floor, such as a roof terrace, or as a means of escape.
ii. The structure is essential for the stability of an external wall that needs to be fire resisting (e.g. to achieve compartmentation or for the purposes of preventing fire spread between buildings).
b. The lowest floor of the building.
c. External walls, such as curtain walls or other forms of cladding, which transmit only self weight and wind loads and do not transmit floor load.
NOTE: In some cases, structural members within a roof may be essential for the structural stability system of the building. In these cases, the structural members in the roof do not just support a roof and must demonstrate the relevant fire resistance for the building as required by paragraph 5.2 above.
The following are excluded from the definition of ‘element of structure’.
a. A structure that supports only a roof, unless either of the following applies.
i. The roof performs the function of a floor, such as for parking vehicles, or as a means of escape.
ii. The structure is essential for the stability of an external wall that needs to be fire resisting (e.g. to achieve compartmentation or for the purposes of preventing fire spread between buildings).
b. The lowest floor of the building.
c. A platform floor.
d. External walls, such as curtain walls or other forms of cladding, which transmit only self weight and wind loads and do not transmit floor load.
NOTE: In some cases, structural members within a roof may be essential for the structural stability system of the building. In these cases, the structural members in the roof do not just support a roof and must demonstrate the relevant fire resistance for the building as required by the note to paragraph 6.1 above.
density
NOTES:
1. As an alternative to using the values in the table, the floor space factor may be determined by reference to actual data taken from similar premises. Where appropriate, the data should reflect the average occupant density at a peak trading time of year.
2. Where accommodation is not directly covered by the descriptions given, a reasonable value based on a similar use may be selected.
3. Where any part of the building is to be used for more than one type of accommodation, the most onerous factor(s) should be applied. Where the building contains different types of accommodation, the occupancy of each different area should be calculated using the relevant space factor.
4. For detailed guidance on appropriate floor space factors for concourses in sports grounds refer to Concourses published by the Football Licensing Authority.
5. Alternatively the occupant number may be taken as the number of fixed seats provided, if the occupants will normally be seated.
6. Shops excluding those under item 10, but including: supermarkets and department stores (main sales areas), shops for personal services, such as hairdressing, and shops for the delivery or collection of goods for cleaning, repair or other treatment or for members of the public themselves carrying out such cleaning, repair or other treatment.
7. Shops (excluding those in covered shopping complexes but including department stores) trading predominantly in furniture, floor coverings, cycles, prams, large domestic appliances or other bulky goods, or trading on a wholesale self-selection basis (cash and carry).
To reduce the testing burden on manufacturers, BS EN 13238 defines a number of standard substrates that produce test results representative of different end use applications. The classification for reaction to fire achieved during testing is only valid when the product is used within this field of application, i.e. when the product is fixed to a substrate of that class in its end use. The standard substrate selected for testing should take account of the intended end use applications (field of application) of the product and represent end use substrates that have a density of a minimum of 75 of the standard substrate's nominal density.
Standard substrates include gypsum plasterboard (BS EN 520) with a density of 700+/-100kg/m3,
calcium silicate board (BS EN 14306) 870+/-50kg/m3 and fibre-cement board 1800+/-200kg/m3.
NOTE: Standard calcium silicate board is not representative of gypsum plasterboard end use (due
to the paper layer), but would be representative of most gypsum plasters (with densities of more
than 650kg/m3).
NOTE: Classifications based on tests using a plasterboard substrate
design
Guidance on the design and construction of fire mains is given in BS 9990.
design and build
B3.(1) The building shall be designed and constructed so that, in the event of fire, its stability will be maintained for a reasonable period
(2) A wall common to two or more buildings shall be designed and constructed so that it adequately resists the spread of fire between those buildings.
For the purposes of this sub-paragraph a house in a terrace and a semi-detached house are each to be treated as a separate building.
(3) Where reasonably necessary to inhibit the spread of fire within the building, measures shall be taken, to an extent appropriate to the size and intended use of the building, comprising either or both of the following—
(a) sub-division of the building with fire-resisting construction;
(b) installation of suitable automatic fire suppression systems.
(4) The building shall be designed and constructed so that the unseen spread of fire and smoke within concealed spaces in its structure and fabric is inhibited.
Requirement B3(3) does not apply to material alterations to any prison provided under section 33 of the Prison Act 1952.
BS 7974 and supporting published documents (PDs) provide a framework for and guidance on the application of fire safety engineering principles to the design of buildings.
Guidance on the design, installation and maintenance of measures to contain fires or slow their spread is given in Ensuring Best Practice for Passive Fire Protection in Buildings produced by the Association for Specialist Fire Protection (ASFP).
design queries
Paragraph 3.27 may be modified using the guidance in clause 7.3 of BS 9991.
designation system
Fire detection and alarm systems must be properly designed, installed and maintained. A design,
installation and commissioning certificate should be provided for fire detection and alarm systems.
Third party certification schemes for fire protection products and related services are an effective
means of providing assurances of quality, reliability and safety.
The records should include details of all of the following. d. All passive fire safety measures, including all of the following. e. All of the following.
a. The fire safety strategy, including all assumptions in the design of the fire safety systems (such as fire load). Any risk assessments or risk analysis.
b. All assumptions in the design of the fire safety arrangements for the management of the building.
c. All of the following.
i. Escape routes (including occupant load and capacity of escape routes).
ii. Any provision to enable the evacuation of disabled people.
iii. Escape strategy (e.g. simultaneous or phased).
iv. Muster points.
i. Compartmentation (i.e. location of fire-separating elements).
ii. Cavity barriers.
iii. Fire doorsets, including fire doorsets fitted with a self-closing device and other doors equipped with relevant hardware (e.g. electronic security locks).
iv. Duct dampers.
v. Fire shutters.
i. Fire detector heads.
ii. Smoke detector heads.
iii. Alarm call points.
iv. Detection/alarm control boxes.
v. Alarm sounders.
vi. Emergency communications systems.
vii. CCTV.
viii. Fire safety signage.
ix. Emergency lighting.
x. Fire extinguishers.
xi. Dry or wet fire mains and other firefighting equipment.
xii. Other interior facilities for the fire and rescue service.
xiii. Emergency control rooms.
xiv. Location of hydrants outside the building.
xv. Other exterior facilities for the fire and rescue service.
f. All active fire safety measures, including both of the following.
i. Sprinkler system(s) design, including isolating valves and control equipment.
ii. Smoke control system(s) (or heating, ventilation and air conditioning system with a smoke control function) design, including mode of operation and control systems.
g. Any high risk areas (e.g. heating machinery) and particular hazards.
h. Plans of the building as built, showing the locations of the above.
i. Both of the following.
i. Specifications of any fire safety equipment provided, including all of the following.
• Operational details.
• Operators’ manuals.
• Software.
• System zoning.
• Routine inspection, testing and maintenance schedules.
ii. Records of any acceptance or commissioning tests.
j. Any other details appropriate for the specific building.
The records should include details of all of the following.
a. The fire safety strategy, including all assumptions in the design of the fire safety systems (such as fire load). Any risk assessments or risk analysis.
The records should include details of all of the following.
f. All active fire safety measures, including both of the following.
i. Sprinkler system(s) design, including isolating valves and control equipment.
ii. Smoke control system(s) (or heating, ventilation and air conditioning system with a smoke control function) design, including mode of operation and control systems.
See Diagram 2.1d. In addition to meeting the provisions in paragraph 2.5, the dwellinghouse should comply with either of the following.
a. Provide an alternative escape route from each storey more than 7.5m above ground level. At the first storey above 7.5m, the protected stairway should be separated from the lower storeys by fire resisting construction (minimum REI 30) if the alternative escape route is accessed via either of the following.
i. The protected stairway to an upper storey.
ii. A landing within the protected stairway enclosure to an alternative escape route on the same storey. The protected stairway at or about 7.5m above ground level should be separated from the lower storeys or levels by fire resisting construction (see Diagram 2.4).
b. Provide a sprinkler system throughout, designed and installed in accordance with BS 9251.
All of the following precautions should be taken to avoid the spread of smoke and fire to the protected stairway.
a. Transfer grilles should not be fitted in any wall, door, floor or ceiling of the stair enclosure.
b. Any duct passing through the stair enclosure should be rigid steel. Joints between the ductwork and stair enclosure should be fire-stopped.
c. Ventilation ducts supplying or extracting air directly to or from a protected stairway should not serve other areas as well.
d. Any system of mechanical ventilation which recirculates air and which serves both the stair and other areas should be designed to shut down on the detection of smoke within the system.
e. For ducted warm air heating systems, a room thermostat should be sited in the living room. It should be mounted at a height between 1370mm and 1830mm above the floor. The maximum setting should be 27°C.
NOTE: Ventilation ducts passing through compartment walls should comply with the guidance in Section 9.
For systems circulating air only within an individual flat, take all of the following precautions.
a. Transfer grilles should not be fitted in any wall, door, floor or ceiling of the enclosure.
b. Any duct passing through the enclosure should be rigid steel. Joints between the ductwork and enclosure should be fire-stopped.
c. Ventilation ducts serving the enclosure should not serve any other areas.
d. Any system of mechanical ventilation which recirculates air and which serves both the stair and other areas should be designed to shut down on the detection of smoke within the system.
e. For ducted warm air heating systems, a room thermostat should be sited in the living room. It should be mounted at a height between 1370mm and 1830mm above the floor. The maximum setting should be 27°C.
NOTE: Ventilation ducts passing through compartment walls should comply with the guidance in Section 9.
Guidance on the design of smoke control systems that use pressure differentials is available in BS EN 12101-6.
Insulating core panels consist of an inner core of insulation sandwiched between, and bonded to, a membrane, such as galvanised steel or aluminium.
Where they are used internally they can present particular problems with regard to fire spread and should meet all of the following conditions.
a. Panels should be sealed to prevent exposure of the core to a fire. This includes at joints and where services penetrate the panel.
b. In high fire risk areas, such as kitchens, places of special fire hazard, or in proximity to where hot works occur, only class A1 cored panels should be used.
c. Fixing systems for all panels should be designed to take account of the potential for the panel to delaminate. For instance, where panels are used to form a suspended ceiling, the fixing should pass through the panel and support it from the lower face.
Under fire conditions, ventilation and air-conditioning systems should be compatible with smoke control systems and need to be considered in their respective design.
For non-residential sprinkler systems designed and installed to BS EN 12845, water supplies should
consist of either of the following.
a. Two single water supplies complying with clause 9.6.1, independent of each other.
b. Two stored water supplies meeting all of the following conditions.
i. Gravity or suction tanks should satisfy all the requirements of clause 9.6.2(b), other than
capacity.
ii. Any pump arrangements should comply with clause 10.2.
iii. In addition to meeting the requirements for inflow, either of the following should apply.
• The capacity of each tank should be at least half the specified minimum water volume
of a single full capacity tank, appropriate to the hazard.
• One tank should be at least equivalent to half the specified water volume of a single
full capacity tank, and the other shall not be less than the minimum volume of a
reduced capacity tank (see clause 9.3.4) appropriate to the hazard.
The total capacity of the water supply in (iii), including any inflow for a reduced capacity
tank, should be at least that of a single full holding capacity tank that complies with
designer
BS 7974 and supporting published documents (PDs) provide a framework for and guidance on the application of fire safety engineering principles to the design of buildings.
In sheltered housing, the guidance in Approved Document B Volume 2 should be consulted for the design of communal facilities, such as a common lounge.
Guidance on the design and construction of fire mains is given in BS 9990.
Guidance on the design of smoke control systems that use pressure differentials is available in BS EN 12101-6.
Under fire conditions, ventilation and air-conditioning systems should be compatible with smoke control systems and need to be considered in their respective design.
diagram d2 cubic capacity
In every case measure the volume contained by all of the following.
a. Under surface of roof.
b. Upper surface of lowest floor.
c. Inner surface of enclosing walls.
When there is not an outer enclosingwall, measure to the outermost edge of the floor slab.
The measured volume should include internal walls and partitions.
a. Cubic capacity of a building Internal wall or partition
b. Cubic capacity of compartments or separated part of a building
Diagram D2 Cubic capacity
diagram d3 area
Exclude external walls of stairways in a protected shaft when assessing unprotected areas (see Diagram 11.5).
In an otherwise protected wall, small unprotected areas may be ignored where they meet the conditions in Diagram 11.5.
Where a fire resisting external wall has an external surface material that is worse than class B-s3, d2 and is more than 1mm thick, that part of the wall should be classified as an unprotected area equating to half its area (Diagram 11.4).
Unprotected areas should meet the conditions in Diagram 11.5, and the rest of the wall should be fire resisting from both sides.
External surface materials facing the boundary should be class B-s3, d2 or better.
a. SMALL SINGLE STAIR BUILDING
*If smoke control is provided in the lobby, the travel distance can be increased to 7.5m maximum(see Diagram 3.7, example b).
b. SMALL SINGLE STAIR BUILDING WITH NO MORE THAN TWO FLATS PER STOREY
The door between stair and lobby should be free from security fastenings.
If the flats have protected entrance halls, the lobby between the common stair and flat entrance is not essential.
NOTES:
1. The arrangements shown also apply to the top storey.
2. If the travel distance across the lobby in diagram (a) exceeds 4.5m, Diagram 3.7 applies.
3. Where,in Diagram (b), the lobby between the common stair and the dwelling is omitted in smal lsingle stair buildings, an automatic opening vent with a free area of at least 1m2 is required at the top of the stair,which is operated automatically on detection of smoke at any storey in the stair.
4. For further guidance on the fire rating of the fire doorsets from the corridor to the flat and/or stairway refer to Appendix C, Table C1.
Fire resisting construction
Openable vent at high level for fire service use (1.0m2 minimum free area); see paragraph 3.28eSee para 3.28
Diagram 3.9
Blocks of flats with a top storey more than 11m above ground level (see Diagram D6) should be fitted with a sprinkler system throughout the building in accordance with Appendix E.
NOTE: Sprinklers should be provided within the individual flats, they do not need to be provided in the common areas such as stairs, corridors or landings when these areas are fire sterile.
The free area of a smoke ventilator should be measured by either of the following.
a. The declared aerodynamic free area in accordance with BS EN 12101-2.
b. The total unobstructed cross-sectional area (geometric free area), measured in the plane where
the area is at a minimum and at right angles to the direction of air flow (Diagram D7).
diagram d4 height of building
In buildings that include a ‘residential’ purpose (purpose groups 1 and 2) with a storey 11m or more in height (see Diagram D6 in Appendix D) balconies should meet either of the following conditions.
a. Only contain materials achieving class A1 or A2-s1, d0, except for any of the following.
i. Cavity trays when used between two leaves of masonry.
ii. Intumescent and fire-stopping materials where the inclusion of the materials is necessary to meet the requirements of Part B of Schedule 1 to the Building Regulations 2010.
iii. Membranes.
iv. Seals, gaskets, fixings, sealants and backer rods.
v. Thermal break materials where the inclusion of the materials is necessary to meet the thermal bridging requirements of Part L of Schedule 1 to the Building Regulations 2010.
vi. Any material achieving class A1fl or A2fl-s1 when it forms the top horizontal floor layer of a balcony and is provided with an imperforate substrate under it which extends to the full size of the class A1fl or A2fl-s1 material.
vii. Electrical installations.
viii. Fibre optic cables.
b. Achieve both of the following conditions.
Have an imperforate soffit which extends to the full area of the balcony, achieves a minimum REI 30 rating and is constructed of materials achieving class A2-s1, d0 or better.
ii. Materials achieving class B-s1, d0 or worse extending beyond the boundary of a single
compartment should include a band of material rated class A2-s1, d0 or better, a minimum of 300mm in width centred on that boundary line.
Where regulation 7(2) applies, that regulation prevails over all the provisions in this paragraph.
In a building with a storey 18m or more in height (see Diagram D6 in Appendix D) any insulation product, filler material (such as the core materials of metal composite panels, sandwich panels and window spandrel panels but not including gaskets, sealants and similar) etc. used in the construction of an external wall should be class A2-s3, d2 or better (see Appendix B). This restriction does not apply to masonry cavity wall construction which complies with Diagram 8.2 in Section 8. Where regulation 7(2) applies, that regulation prevails over all the provisions in this paragraph.
In buildings that include a ‘residential’ purpose (purpose groups 1 and 2) with a storey 11m or more in height (see Diagram D6 in Appendix D) any insulation product, filler material (such as the core materials of metal composite panels, sandwich panels and window spandrel panels but not including gaskets, sealants and similar) etc. used in the construction of an external wall should be class A2-s1, d0 or better (see Appendix B). This restriction does not apply to masonry cavity wall construction which complies with Diagram 8.2 in Section 8. Where regulation 7(2) applies, that regulation prevails over all the provisions in this paragraph.
direct distance
In every case measure the volume contained by all of the following.
a. Under surface of roof.
b. Upper surface of lowest floor.
c. Inner surface of enclosing walls.
When there is not an outer enclosingwall, measure to the outermost edge of the floor slab.
The measured volume should include internal walls and partitions.
a. Cubic capacity of a building Internal wall or partition
b. Cubic capacity of compartments or separated part of a building
Diagram D2 Cubic capacity
a. Surface area: roofs and rooflights In each case measure the visible area
b. Floor area: Room, garage, conservatory or outbuilding, measure to inner surface of enclosing walls
c. Floor area: Storey, part or compartment, measure to inner surface of enclosing walls and include internal walls and partitions
NOTES:
1.Hose laying distance should be measured from the fire main outlet along the route suitable for laying hose. If this route is not known, the distance should be taken at two-thirds of the direct distance
2.The fire main outlet should be located according to Section 14.
See para 15.7
Firefighting shafts and protected stairways should be positioned such that every part of each storey more than 18m above the fire and rescue service vehicle access level complies with the maximum distances given in paragraph 15.7. Distances should be measured from the fire main outlet on a route suitable for laying a hose.
NOTE: If the internal layout is not known, the distance should be measured at two-thirds of the direct distance.
A passenger lift serving any storey more than 4.5m above ground level should be in either of the following.
a. The enclosure to the protected stairway, as described in paragraph 2.5.
b. A fire resisting lift shaft (minimum REI 30).
NOTES:
1. If travel distance is measured to a stair lobby, the lobby must not provide direct access to any storage room, flat or other space containing a fire hazard.
2. In the case of a small single stair building in accordance with Diagram 3.9, this is reduced to 4.5m.
3. Does not apply if all flats on a storey have independent alternative means of escape.
4. Sheltered housing may require reduced maximum travel distances.
Configurations of stairs and external wall
Fire resisting construction
Fire resisting construction of adjacent building enclosure of protected stairway
Non-fire resisting construction
See para 3.63
In buildings designed for phased evacuation or progressive horizontal evacuation, if the lift well is not within the enclosures of a protected stairway, its entrance should be separated at every storey by a protected lobby (minimum REI 30).
In basements and enclosed car parks, the lift should be within the enclosure of a protected stairway. Otherwise, the lift should be approached only via a protected lobby or protected corridor (minimum REI 30).
From the flat entrance door, a single escape route is acceptable in either of the following cases.
a. The flat is on a storey served by a single common stair and both of the following apply.
i. Every flat is separated from the common stair by a protected lobby or common protected corridor (see Diagram 3.7).
ii. The maximum travel distance in Table 3.1, for escape in one direction only, is not exceeded.
b. The flat is in a dead end of a common corridor served by two (or more) common stairs and the maximum travel distance given in Table 3.1, for escape in one direction only, is not exceeded (Diagram 3.8).
Every common stair should be a protected stairway. Where the protected stairway passes from one compartment to another, it should be within a protected shaft.
With some configurations of external wall, a fire in one part of a building could subject the external wall of a protected stairway to heat (for example, where the two are adjacent at an internal angle in the façade, as shown in Diagram 3.10).
See paras 3.27 and 3.36
NOTES:
1. The arrangements shown also apply to the top storey.
2. See Diagram 3.9 for small single stair buildings.
3. All doors shown are fire doorsets.
4. Where travel distance is measured to a stair lobby, the lobby must not provide direct access to any storage room, flat or other space containing a potential fire hazard.
5. For further guidance on the fire rating of the fire doorsets from the corridor to the flat and/or stairway refer to Appendix C ,Table C1.
F Flat
Shaded areas indicate zones where ventilation should be provided in accordance with paragraphs 3.50 to 3.53(An external wall vent or smoke shaft located anywhere in the shaded area)
See paras 3.27 and 3.36
NOTES:
1. The arrangements shown also apply to the top storey.
2. See Diagram 3.9 for small single stair buildings.
3. All doors shown are fire doorsets.
4. Where travel distance is measured to a stair lobby, the lobby must not provide direct access to any storage room, flat or other space containing a potential fire hazard.
5. For further guidance on the fire rating of the fire doorsets from the corridor to the flat and/or stairway refer to Appendix C ,Table C1.
F Flat
Shaded areas indicate zones where ventilation should be provided in accordance with paragraphs 3.50 to 3.53(An external wall vent or smoke shaft located anywhere in the shaded area)
If glazed elements in fire resisting enclosures and doors can only meet the required integrity performance, their use is limited. These limitations depend on whether the enclosure forms part of a protected shaft (see Section 7) and the provisions set out in Appendix B, Table B5. If both integrity and insulation performance can be met, there is no restriction in this document on the use or amount of glass.
Lift wells should comply with one of the following conditions.
a. Be sited within the enclosures of a protected stairway.
b. Be enclosed with fire resisting construction (minimum REI 30) when in a position that might prejudice the means of escape.
direct transmission
A stair of acceptable width for everyday use will be sufficient for escape purposes. If it is also a firefighting stair, it should be at least 1100mm wide. The width is the clear width between the walls or balustrades. Any handrails and strings intruding into that width by a maximum of 100mm on each side may be ignored.
If one element of structure supports or stabilises another, as a minimum the supporting element should have the same fire resistance as the other element.
display window
If glazed elements in fire resisting enclosures and doors can only meet the required integrity performance, their use is limited. These limitations depend on whether the enclosure forms part of a protected shaft (see Section 7) and the provisions set out in Appendix B, Table B5. If both integrity and insulation performance can be met, there is no restriction in this document on the use or amount of glass.
Glazed elements should also comply with the following, where necessary.
a. If the enclosure forms part of a protected shaft: Section 7.
b. Appendix B, Table B5.
c. Guidance on the safety of glazing: Approved Document K.
Doors should contain vision panels in both of the following situations.
a. Where doors on escape routes divide corridors.
b. Where doors are hung to swing both ways.
Approved Document M contains guidance about vision panels in doors across accessible corridors and Approved Document K contains guidance about the safety of glazing.
Thermoplastic material classified as a TP(a) rigid product may be used to glaze external windows to rooms, but not external windows to circulation spaces. Approved Document K includes guidance on the safety of glazing.
An uninsulated glazed screen may be incorporated in the enclosure to a protected shaft between a stair and a lobby or corridor entered from the stair. The enclosure must conform to Diagram 7.2 and meet all of the following conditions.
a. The standard of fire resistance required for the protected stairway is not more than REI 60.
b. The glazed screen complies with the following.
i. It achieves a minimum rating of E 30.
ii. It complies with the guidance on limits on areas of uninsulated glazing in Appendix B, Table B5.
c. The lobby or corridor is enclosed with fire resisting construction achieving a minimum rating of REI 30.
document type
Smoke and heat alarms should have a standby power supply, such as a battery (rechargeable
or non-rechargeable) or capacitor. More information on power supplies is given in clause 15 of
BS 5839-6.
NOTE: The term ‘fire alarm system’ describes the combination of components for giving an audible
and/or other perceptible warning of fire.
NOTE: In this document, the term ‘fire detection system’ describes any type of automatic sensor
network and associated control and indicating equipment. Sensors may be sensitive to smoke,
heat, gaseous combustion products or radiation. Automatic sprinkler systems can also be used to
operate a fire alarm system.
documents (housing)
While many of the provisions in this approved document for means of escape from flats are applicable to sheltered housing, the nature of the occupancy may necessitate some additional fire protection measures. The extent of such measures will depend on the form of the development. For example, a group of specially adapted bungalows or two storey flats, with few communal facilities, will not need to be treated differently from other single storey or two storey dwellinghouses or flats.
In sheltered housing, the guidance in Approved Document B Volume 2 should be consulted for the design of communal facilities, such as a common lounge.
doorset
Effective clear width (door stop to projecting ironmongery)
Effective clear width (door stop to door leaf)
Effective clear width (door stop to projecting ironmongery)
Effective clear width (door stop to door leaf)
See para 2.5
Fire resisting construction minimum REI 30
Fd Fire doorset minimum E 20
No fire resistance required for door
1100mm zone above top landing
1100mm zone above top landing
6m maximum height of stair
Fire resisting window (minimum RE30)
1800mm zone of fire resisting construction at side of stair
Fire doorset (minimum E30)
Ground level or a roof or podium served by an independent stairway
6m maximum height of stair without weather protection
9m zone of fire resisting construction below stair
Ground level or a roof or podium served by an independent stairway
See para 3.68
See para 3.18
NOTE: Bathrooms do not need to have fire doorsets provided that the bathroom is separated by fire resisting construction from the adjacent rooms.
Divide a common corridor connecting two or more storey exits with a fire doorset fitted with a self-closing device (minimum E 30 Sa). See Diagram 3.8. Associated screens should be fire resisting. Site doors so that smoke does not affect access to more than one stair.
A fire doorset (minimum E 30 Sa) fitted with a self-closing device (and fire resisting screen, where required) should separate the dead-end portion of a common corridor from the rest of the corridor (Diagrams 3.7a, 3.8b and 3.8c).
See paras 3.27 and 3.36
NOTES:
1. The arrangements shown also apply to the top storey.
2. See Diagram 3.9 for small single stair buildings.
3. All doors shown are fire doorsets.
4. Where travel distance is measured to a stair lobby, the lobby must not provide direct access to any storage room, flat or other space containing a potential fire hazard.
5. For further guidance on the fire rating of the fire doorsets from the corridor to the flat and/or stairway refer to Appendix C ,Table C1.
F Flat
Shaded areas indicate zones where ventilation should be provided in accordance with paragraphs 3.50 to 3.53(An external wall vent or smoke shaft located anywhere in the shaded area)
See paras 3.27 and 3.36
NOTES:
1. The arrangements shown also apply to the top storey.
2. See Diagram 3.9 for small single stair buildings.
3. All doors shown are fire doorsets.
4. Where travel distance is measured to a stair lobby, the lobby must not provide direct access to any storage room, flat or other space containing a potential fire hazard.
5. For further guidance on the fire rating of the fire doorsets from the corridor to the flat and/or stairway refer to Appendix C ,Table C1.
F Flat
Shaded areas indicate zones where ventilation should be provided in accordance with paragraphs 3.50 to 3.53(An external wall vent or smoke shaft located anywhere in the shaded area)
a. CORRIDOR ACCESS WITHOUT DEAD ENDS
b. CORRIDOR ACCESS WITH DEAD ENDS
The central door may be omitted if maximum travel distance is not more than 15m.
1. The arrangements shown also apply to the top storey.
2. For further guidance on the fire rating of the fire doorsets from the corridor to the flat and/or stairway refer to Appendix C ,Table C1.
Fire doorset provided in accordance with paragraphs 3.50 to 3.53(An external wall vent or smoke shaft located anywhere in the shaded area)
See paras 3.27 and 3.36
Doors should be readily openable to avoid undue delay to people escaping. Doors on escape routes (both within and from the building) should comply with paragraphs 3.91 to 3.98. Guidance on door closing and ‘hold open’ devices for fire doorsets is set out in Appendix C.
NOTE: Paragraphs 3.91 to 3.98 do not apply to flat entrance doors.
Doors should contain vision panels in both of the following situations.
a. Where doors on escape routes divide corridors.
b. Where doors are hung to swing both ways.
Approved Document M contains guidance about vision panels in doors across accessible corridors and Approved Document K contains guidance about the safety of glazing.
Fire resistance to protected shaft to be a maximum of REI 60
Fire resistance of construction to be a minimum of REI 30 (including fire doorsets that are a minimum of E 30 Sa)
Fire resistance of glazing to be a minimum of RE 30(including fire doorsets that are a minimum of E 30 Sa)
a. WITH CORRIDOR
b. WITH LOBBY
See para 7.25
The external wall of a protected shaft does not normally need to have fire resistance. Situations where there are provisions are given in paragraph 3.63 (external walls of protected stairways, which may also be protected shafts) and paragraphs 15.8 to 15.11 (firefighting shafts).
Openings in other parts of the enclosure to a protected shaft should be limited to the following.
a. If a wall common to two or more buildings forms part of the enclosure, only the following openings should be made in that wall.
i. A fire doorset providing a means of escape, which has the same fire resistance as the wall and is fitted in accordance with the provisions in Appendix C.
ii. The passage of a pipe that meets the provisions in Section 9.
b. Other parts of the enclosure (other than an external wall) should only have openings for any of the following.
i. Fire doorsets of the appropriate fire resistance, fitted in accordance with the provisions in Appendix C.
ii. The passage of pipes which meet the provisions in Section 9.
iii. Inlets to, outlets from and openings for a ventilation duct (if the shaft contains or serves as a ventilating duct), meeting the provisions in Section 9.
iv. The passage of lift cables into a lift machine room (if the shaft contains a lift). If the machine room is at the bottom of the shaft, the openings should be as small as practicable.
All fire doorsets should have the performance shown in Table C1, based on one of the following.
a. Fire resistance in terms of integrity, for a period of minutes, when tested to BS 476-22, e.g. FD 30.
A suffix (S) is added for doorsets where restricted smoke leakage at ambient temperatures is
needed.
b. As determined with reference to Commission Decision 2000/367/EC regarding the
classification of the resistance to fire performance of construction products, construction
works and parts thereof. All fire doorsets should be classified in accordance with BS EN 13501-2,
tested to the relevant European method from the following.
i. BS EN 1634-1.
ii. BS EN 1634-2.
iii. BS EN 1634-3.
c. As determined with reference to European Parliament and Council Directive 95/16/EC (which
applies to lifts that permanently serve buildings and constructions and specified safety
components) on the approximation of laws of Member States relating to lifts (‘Lifts Directive’)
implementing the
Unless shown to be satisfactory when tested as part of a fire doorset assembly, the essential components of any hinge on which a fire door is hung should be made entirely from materials that have a minimum melting point of 800°C.
Except for doorsets listed in paragraph C12, all fire doorsets should be marked with one of the
following fire safety signs, complying with BS 5499-5, as appropriate.
a. To be kept closed when not in use – mark ‘Fire door keep shut’.
b. To be kept locked when not in use – mark ‘Fire door keep locked shut’.
c. Held open by an automatic release mechanism or free swing device – mark ‘Automatic fire door
keep clear’.
All fire doorsets should be marked on both sides, except fire doorsets to cupboards and service
ducts, which should be marked on the outside.
The following fire doorsets are not required to comply with paragraph C11.
a. Doors to and within flats and dwellinghouses.
b. Bedroom doors in ‘residential (other)’ (purpose group 2(b)) premises.
c. Lift entrance/landing doors.
The performance of some doorsets set out in Table C1 is linked to the minimum periods of fire resistance for elements of structure given in Tables B3 and B4. Limitations on the use of uninsulated glazing in fire doorsets are given in Table B5.
Recommendations for the specification, design, construction, installation and maintenance of fire
doorsets constructed with non-metallic door leaves are given in BS 8214.
Guidance on timber fire resisting doorsets, in relation to the new European test standard, may be
found in Timber Fire Resisting Doorsets: Maintaining Performance Under the New European Test
Standard published by the Timber Research and Development Association (TRADA).
Guidance for metal doors is given in Code of Practice for Fire Resisting Metal Doorsets published by
the Door and Shutter Manufacturers’ Association (DSMA).
The requirement is for test exposure from each side of the doorset separately. The exception is lift doors, which are tested from the landing side only.
Any test evidence used to verify the fire resistance rating of a doorset or shutter should be
checked to ensure both of the following.
a. It adequately demonstrates compliance.
b. It is applicable to the complete installed assembly. Small differences in detail may significantly
affect the rating.
Until relevant harmonised product standards are published, for the purposes of meeting the
Building Regulations, products tested in accordance with BS EN 1634-1 (with or without pre-fire test
mechanical conditioning) that achieve the minimum performance in Table C1 will be deemed to
satisfy the provisions.
All fire doorsets, including to flat entrances and between a dwellinghouse and an integral garage,
should be fitted with a self-closing device, except for all of the following.
a. Fire doorsets to cupboards.
b. Fire doorsets to service ducts normally locked shut.
c. Fire doorsets within flats and dwellinghouses.
Two fire doorsets may be fitted in the same opening if each door is capable of closing the opening,
so the total fire resistance is the sum of their individual resistances. If the opening is provided as a
means of escape, both fire doorsets should be self-closing.
If one fire doorset is capable of being easily opened by hand and has a minimum of 30 minutes’ fire
resistance, the other fire doorset should comply with both of the following.
a. Be fitted with an automatic self-closing device.
b. Be held open by a fusible link.
Fire doorsets often do not provide any significant insulation. Unless providing both integrity
and insulation in accordance with Appendix B, Table B3, a maximum of 25% of the length of a
compartment wall should consist of door openings.
Where it is practicable to maintain a clear space on both sides of the doorway, the above
percentage may be greater.
draught break
Any door opening towards a corridor or a stair should be recessed to prevent its swing encroaching on the effective width.
drawing 2d
For the systems described in paragraph E5, both of the following apply if pumps are used to draw
water from two tanks.
a. Each pump should be able to draw water from either tank.
b. Any one pump, or either tank, should be able to be isolated.
The sprinkler water supplies should not be used as connections for other services or other fixed
firefighting systems.
duties
Provisions covering access and facilities for the fire service are to safeguard the health and safety of
people in and around the building. Their extent depends on the size and use of the building. Most
firefighting is carried out within the building. In the Secretary of State’s view, requirement B5 is met
by achieving all of the following.
a. External access enabling fire appliances to be used near the building.
b. Access into and within the building for firefighting personnel to both:
i. search for and rescue people
ii. fight fire.
c. Provision for internal fire facilities for firefighters to complete their tasks.
d. Ventilation of heat and smoke from a fire in a basement.
If an alternative approach is taken to providing the means of escape, outside the scope of this
approved document, additional provisions for firefighting access may be required. Where deviating
from the general guidance, it is advisable to seek advice from the fire and rescue service as early as
possible (even if there is no statutory duty to consult).
e. A facility to store building information for firefighters to complete their tasks.
dwelling
All dwellings should have a fire detection and alarm system, minimum Grade D2 Category LD3
standard, in accordance with the relevant recommendations of BS 5839-6.
A higher standard of protection should be considered where occupants of a proposed dwelling
would be at special risk from fire. Further advice on this is also given in BS 5839-6.
All dwellings should have a fire detection and alarm system, minimum Grade D2 Category LD3
standard, in accordance with the relevant recommendations of BS 5839-6.
A higher standard of protection should be considered where occupants of a proposed dwelling
would be at special risk from fire. Further advice on this is also given in BS 5839-6.
Smoke alarms should be provided in the circulation spaces of the dwelling in accordance with paragraphs 1.1 to 1.4.
Smoke alarms should be provided in the circulation spaces of the dwelling in accordance with paragraphs 1.1 to 1.4.
dwelling type
NOTES:
1. As an alternative to using the values in the table, the floor space factor may be determined by reference to actual data taken from similar premises. Where appropriate, the data should reflect the average occupant density at a peak trading time of year.
2. Where accommodation is not directly covered by the descriptions given, a reasonable value based on a similar use may be selected.
3. Where any part of the building is to be used for more than one type of accommodation, the most onerous factor(s) should be applied. Where the building contains different types of accommodation, the occupancy of each different area should be calculated using the relevant space factor.
4. For detailed guidance on appropriate floor space factors for concourses in sports grounds refer to Concourses published by the Football Licensing Authority.
5. Alternatively the occupant number may be taken as the number of fixed seats provided, if the occupants will normally be seated.
6. Shops excluding those under item 10, but including: supermarkets and department stores (main sales areas), shops for personal services, such as hairdressing, and shops for the delivery or collection of goods for cleaning, repair or other treatment or for members of the public themselves carrying out such cleaning, repair or other treatment.
7. Shops (excluding those in covered shopping complexes but including department stores) trading predominantly in furniture, floor coverings, cycles, prams, large domestic appliances or other bulky goods, or trading on a wholesale self-selection basis (cash and carry).
All dwellings should have a fire detection and alarm system, minimum Grade D2 Category LD3
standard, in accordance with the relevant recommendations of BS 5839-6.
A higher standard of protection should be considered where occupants of a proposed dwelling
would be at special risk from fire. Further advice on this is also given in BS 5839-6.
In student residences that are designed and occupied as a block of flats, separate automatic detection should be provided in each self-contained flat where all of the following apply.
a. A group of up to six students shares the flat.
b. Each flat has its own entrance door.
c. The compartmentation principles for flats in Section 7 have been followed.
Where a total evacuation strategy is adopted, the alarm system should follow the guidance for buildings other than dwellings in Volume 2 of Approved Document B.
Smoke alarms should be provided in the circulation spaces of the dwelling in accordance with paragraphs 1.1 to 1.4.
The external surfaces (i.e. outermost external material) of external walls should comply with the provisions in Table 10.1. The provisions in Table 10.1 apply to each wall individually in relation to its proximity to the relevant boundary.
NOTES:
None of the above designations are suitable for protected stairways.
Polycarbonate and uPVC rooflights that achieve a class C-s3, d2 rating by test (see paragraph 12.7) may be regarded as having a BROOF(t4) classification.
Where Diagram 5.2a or 5.2b applies, rooflights should be a minimum of 1500mm from the compartment wall.
If double-skinned or laminate products have upper and lower surfaces of different materials, the greater distance applies.
1. See also the guidance to requirement B2 in Section 4.
2. The designation of external roof surfaces is explained in Appendix B.
3. Single-skinned rooflight only, in the case of non-thermoplastic material.
4. The rooflight should also meet the provisions of Diagram 12.1.
NOTES:
None of the above designations are suitable for protected stairways.
Polycarbonate and uPVC rooflights that achieve a class C-s3, d2 rating by test (paragraph 12.7) may be regarded as having a BROOF(t4) classification.
Where Diagram 5.2a or 5.2b applies, rooflights should be a minimum of 1500mm from the compartment wall.
If double-skinned or laminate products have upper and lower surfaces of different materials, the greater distance applies.
1. See also the guidance to requirement B2 in section 4.
2. No limit in the case of any space described in 2a, b and c.
3. Single-skinned rooflight only, in the case of non-thermoplastic material.
4. The rooflight should also meet the provisions of diagram 12.1.
If the performance of thatch or wood shingles cannot be established, they should be regarded as having an EROOF(t4) classification in Table 12.1.
NOTE: Consideration can be given to thatched roofs being closer to the relevant boundary than shown in Table 12.1 if, for example, all of the following precautions (based on the LABC publication Thatched Buildings (the Dorset Model): New Properties and Extensions) are incorporated in the design.
a. The rafters are overdrawn with construction having not less than 30 minutes’ fire resistance.
b. The guidance given in Approved Document J is followed.
c. The smoke alarm installation (see Section 1) extends to the roof spaces.
NOTES:
1. Fire appliances are not standardised. The building control body may, in consultation with the local fire and rescue service, use other dimensions.
2. The road base can be designed to 12.5 tonne capacity. Structures such as bridges should have the full 17-tonne capacity. The weight of high reach appliances is distributed over a number of axles, so infrequent use of a route designed to accommodate 12.5 tonnes should not cause damage.
For buildings fitted with dry fire mains, both of the following apply.
a. Access should be provided for a pumping appliance to within 18m of each fire main inlet connection point. Inlets should be on the face of the building.
b. The fire main inlet connection point should be visible from the parking position of the appliance, and meet the provisions in Section 8 of BS 9990.
Except in buildings that comply with Diagram 3.9, the corridor or lobby next to each stair should have a smoke vent. The location of the vent should comply with both of the following.
a. Be as high as practicable.
b. Be positioned so the top edge is at least as high as the top of the door to the stair.
In single stair buildings, smoke vents on the storey where the fire is initiated, and the vent at the head of the stair, should be activated by smoke detectors in the common parts.
In buildings with more than one stair, smoke vents may be activated manually. The control system should open the vent at the head of the stair before, or at the same time as, the vent on the storey where the fire is located. Smoke detection is not required for ventilation purposes in this instance.
Fire dampers should meet both of the following conditions.
a. Conform to BS EN 15650.
b. Have a minimum E classification of 60 minutes or to match the integrity rating of the fire resisting elements, whichever is higher.
Fire and smoke dampers should meet both of the following conditions.
a. Conform to BS EN 15650.
b. Have a minimum ES classification of 60 minutes or to match the integrity rating of the fire resisting elements, whichever is higher.
The standards of fire resistance necessary for a particular building are based on assumptions about the severity of fires and the consequences should an element fail. Fire severity is estimated in very broad terms from the use of the building (its purpose group), on the assumption that the building contents (which constitute the fire load) are similar for buildings with the same use.
dwellinghouse
Volume 1 purpose groups
Purpose for which the building or compartment of a building is intended to be used
Residential(dwellings)
1(a)(1)Flat.
1(b)(2)Dwellinghouse that contains a habitable storey with a floor level a minimum of 4.5m above ground level up to a maximum of 18m.
(3)1(c)(2)(4)Dwellinghouse that does not contain a habitable storey with a floor level a minimum of 4.5m above ground level.
While many of the provisions in this approved document for means of escape from flats are applicable to sheltered housing, the nature of the occupancy may necessitate some additional fire protection measures. The extent of such measures will depend on the form of the development. For example, a group of specially adapted bungalows or two storey flats, with few communal facilities, will not need to be treated differently from other single storey or two storey dwellinghouses or flats.
A large dwellinghouse has more than one storey, and at least one storey exceeds 200m2.
A large dwellinghouse of two storeys (excluding basement storeys) should be fitted with a Grade A
Category LD3 fire detection and alarm system, as described in BS 5839-6.
A large dwellinghouse of three or more storeys (excluding basement storeys) should be fitted with
a Grade A Category LD2 fire detection and alarm system as described in BS 5839-6.
Cavity barriers should be provided in accordance with Section 5 in dwellinghouses and Section 8 in flats.
NOTES:
Separation distances do not apply to the boundary between roofs of a pair of semi-detached dwellinghouses and to enclosed/covered walkways. However, see Diagram 5.2 if the roof passes over the top of a compartment wall.
Polycarbonate and uPVC rooflights that achieve a class C-s3, d2 rating by test may be regarded as having a BROOF(t4) designation.
1. The designation of external roof surfaces is explained in Appendix B.
2. Not acceptable on any of the following buildings.
a. Dwellinghouses in terraces of three or more dwellinghouses.
b. Any other buildings with a cubic capacity of more than 1500m3.
3. Acceptable on buildings not listed in (1) if both of the following apply.
a. Part of the roof has a maximum area of 3m2 and is a minimum of 1500mm from any similar part.
b. The roof between the parts is covered with a material rated class A2-s3, d2 or better.
For dwellinghouses, access for a pumping appliance should be provided to within 45m of all points inside the dwellinghouse. Every elevation to which vehicle access is provided should have a suitable door(s), not less than 750mm wide, giving access to the interior of the building.
See paras 2.1 to 2.6
Single storey dwellinghouse(see paragraph 2.1)
Dwellinghouse with one storey more than 4.5m above ground level(see paragraph 2.5)
Dwellinghouse with two or more storeys more than 4.5m above ground level(see paragraph 2.6)
Where an existing window would be an escape window in a new dwellinghouse, and is big enough to be used for escape purposes, then the replacement should comply with one of the following.
a. The replacement window should be sized to provide at least the same potential for escape.
b. If the existing window was larger than required for escape purposes, the opening can be reduced to the minimum described in paragraph 2.10.
Dwellinghouses with one internal stair should comply with paragraphs 2.5 and 2.6. In dwellinghouses with more than one stair, the stairs should provide effective alternative means of escape. The stairs should be physically separated by either of the following.
a. Fire resisting construction (minimum REI 30).
b. More than one room.
Where escape from a dwellinghouse is to an enclosed space with exit only possible through other buildings (e.g. a courtyard or back garden), the length of the space should exceed whichever is the greater of the following.
a. The height of the dwellinghouse above ground level (x).
b. Where a rear extension is provided, the height of the extension (y).
See para 2.10
Air circulation systems which circulate air within an individual dwellinghouse with a floor more than
4.5m above ground level should meet the guidance given in paragraph 2.9.
Separate guidance applies to means of escape within the flat and within the common parts of the building that lead to a place of safety. Flats at ground level are treated similarly to dwellinghouses. With increasing height, more complex provisions are needed.
A multi-storey flat with an independent external entrance at ground level is similar to a dwellinghouse and means of escape should be planned on the basis of Section 2, depending on the height of the top storey above ground level.
Fire doors between the garage and dwellinghouse to have a minimum fire resistance of E30 Sa and be fitted with a self-closing device
Wall and any floor between the garage and dwellinghouse to have a minimum fire resistance of REI 30 from the garage side
The door opening threshold should be a minimum of 100mm above garage floor or
Floor to fall away from door to the outside
See paras 5.6 and 5.7
Where adding an additional storey to a two storey single family dwellinghouse, new floors should have a minimum REI 30 fire resistance. Any floor forming part of the enclosure to the circulation space between the loft conversion and the final exit should achieve a minimum rating of REI 30.
The existing first-storey construction should have a minimum rating of R 30. The fire performance may be reduced for integrity and insulation, when both of the following conditions are met.
a. Only one storey is added, containing a maximum of two habitable rooms.
b. The new storey has a maximum total area of 50m2.
Dwellinghouses that are semi-detached or in terraces should be considered as separate buildings. Every wall separating the dwellinghouses should be constructed as a compartment wall (see paragraphs 5.8 to 5.12).
If a garage is attached to or forms an integral part of a dwellinghouse, the garage should be separated from the rest of the dwellinghouse by fire resisting construction (minimum REI 30) (Diagram 5.1).
Where a door is provided between a dwellinghouse and the garage (see Diagram 5.1), it should meet one of the following conditions.
a. The garage floor should be laid such that it falls away from the door to the outside, to allow fuel spills to flow away.
b. The door opening should be a minimum of 100mm above the level of the garage floor.
Where an existing dwellinghouse or other building is converted into flats, a review of the existing construction should be carried out. Retained timber floors may make it difficult to meet the relevant provisions for fire resistance.
The requirements are the same as for dwellinghouses, detailed in paragraphs 5.11 and 5.12.
The following fire doorsets are not required to comply with paragraph C11.
a. Doors to and within flats and dwellinghouses.
b. Bedroom doors in ‘residential (other)’ (purpose group 2(b)) premises.
c. Lift entrance/landing doors.
All fire doorsets, including to flat entrances and between a dwellinghouse and an integral garage,
should be fitted with a self-closing device, except for all of the following.
a. Fire doorsets to cupboards.
b. Fire doorsets to service ducts normally locked shut.
c. Fire doorsets within flats and dwellinghouses.
dynamic stiffness
The external envelope of a building should not provide a medium for fire spread if it is likely to be a risk to health or safety. The use of combustible materials for cladding framework, or of combustible thermal insulation as an overcladding or in ventilated cavities, may present such a risk in tall buildings, even though the provisions for external surfaces in Diagram 40 may have been satisfied.
In a building with a storey 18m or more above ground level, insulation material used in ventilated cavities in the external wall construction should be of limited combustibility (see Appendix A). This restriction does not apply to masonry cavity wall construction which complies with Diagram 32 in Section 10. Advice on the use of thermal insulation material is given in the BRE Report Fire performance of external thermal insulation for walls of multi-storey buildings (BR 135, 1988).
Guidance on the use of PTFE-based materials for tension-membrane roofs and structures is given in the BRE report BR 274.
earth-closet
To restrict the use of materials which ignite easily, which have a high rate of heat release and/ or which reduce the time to flash over, maximum acceptable 'fire propagation' indices are specified, where the national test methods are being followed.
These are determined by reference to the method specified in BS 476-6:1981 or 1989 Method of test for fire propagation of products. Index of performance (I) relates to the overall test performance, whereas sub-index (i1) is derived from the first 3 minutes of test.
To restrict the use of materials which ignite easily, which have a high rate of heat release and/ or which reduce the time to flashover, maximum acceptable 'fire propagation' indices are specified, where the National test methods are being followed.
These are determined by reference to the method specified in BS 476-6:1981 or 1989 Method of test for fire propagation of products. Index of performance (I) relates to the overall test performance, whereas sub-index (i1) is derived from the first three minutes of test.
NOTE:
1.Wallcoverings which conform to BS EN 15102, achieving at least class C-s3, d2 and bonded to a class A2-s3, d2 substrate, will also be acceptable.
easily accessible
A lift shaft serving storeys above ground level should not serve any basement, if either of the following applies.
a. There is only one escape stair serving storeys above ground level and smoke from a basement fire would adversely affect escape routes in the upper storeys.
b. The lift shaft is within the enclosure to an escape stair that terminates at ground level.
electrical installation*
External fire spread
B4.(1)The external walls of the building shall adequately resist the spread of fire over the walls and from one building to another, having regard to the height, use and position of the building.
(2)The roof of the building shall adequately resist the spread of fire over the roof and from one building to another, having regard to the use and position of the building.
Regulation 7 – Materials and workmanship
(1)Building work shall be carried out—
(a)with adequate and proper materials which—
(i)are appropriate for the circumstances in which they are used,
(ii)are adequately mixed or prepared, and
(iii)are applied, used or fixed so as adequately to perform the functions for which they are designed; and
(b)in a workmanlike manner.
(2)Subject to paragraph (3), building work shall be carried out so that materials which become part of an external wall, or specified attachment, of a relevant building are of European Classification A2-s1, d0 or A1, classified in accordance with BS EN 13501-1:2007+A1:2009 entitled “Fire classification of construction products and building elements. Classification using test data from reaction to fire tests” (ISBN 978 0 580 59861 6) published by the British Standards Institution on 30th March 2007 and amended in November 2009.
(3)Paragraph (2) does not apply to—
(a)cavity trays when used between two leaves of masonry;
(b)any part of a roof (other than any part of a roof which falls within paragraph (iv) of regulation 2(6))if that part is connected to an external wall;
(c)door frames and doors;
(d)electrical installations;
(e)insulation and water proofing materials used below ground level;
(f)intumescent and fire stopping materials where the inclusion of the materials is necessary to meet the requirements of Part B of Schedule 1;
(g)membranes;
(h)seals, gaskets, fixings, sealants and backer rods;
(i)thermal break materials where the inclusion of the materials is necessary to meet the thermal bridging requirements of Part L of Schedule 1; or
(j)window frames and glass.
(4)In this regulation—
(a)a “relevant building” means a building with a storey (not including roof-top plant areas or any storey consisting exclusively of plant rooms) at least 18 metres above ground level and which—
(i)contains one or more dwellings;
(ii)contains an institution; or
(iii)contains a room for residential purposes(excluding any room in a hostel, hotel or boarding house); and
(b)“above ground level” in relation to a storey means above ground level when measured from the lowest ground level adjoining the outside of a building to the top of the floor surface of the storey.
In buildings that include a ‘residential’ purpose (purpose groups 1 and 2) with a storey 11m or more in height (see Diagram D6 in Appendix D) balconies should meet either of the following conditions.
a. Only contain materials achieving class A1 or A2-s1, d0, except for any of the following.
i. Cavity trays when used between two leaves of masonry.
ii. Intumescent and fire-stopping materials where the inclusion of the materials is necessary to meet the requirements of Part B of Schedule 1 to the Building Regulations 2010.
iii. Membranes.
iv. Seals, gaskets, fixings, sealants and backer rods.
v. Thermal break materials where the inclusion of the materials is necessary to meet the thermal bridging requirements of Part L of Schedule 1 to the Building Regulations 2010.
vi. Any material achieving class A1fl or A2fl-s1 when it forms the top horizontal floor layer of a balcony and is provided with an imperforate substrate under it which extends to the full size of the class A1fl or A2fl-s1 material.
vii. Electrical installations.
viii. Fibre optic cables.
b. Achieve both of the following conditions.
Have an imperforate soffit which extends to the full area of the balcony, achieves a minimum REI 30 rating and is constructed of materials achieving class A2-s1, d0 or better.
ii. Materials achieving class B-s1, d0 or worse extending beyond the boundary of a single
compartment should include a band of material rated class A2-s1, d0 or better, a minimum of 300mm in width centred on that boundary line.
Where regulation 7(2) applies, that regulation prevails over all the provisions in this paragraph.
Electrically powered locks should return to the unlocked position in all of the following situations.
a. If the fire detection and alarm system operates.
b. If there is loss of power or system error.
c. If the security mechanism override is activated.
Security mechanism overrides for electrically powered locks should be a Type A call point, as described in BS 7273-4. The call point should be positioned on the side approached by people escaping. If the door provides escape in either direction, a call point should be installed on both sides of the door.
element of structure
In the Secretary of State’s view, requirement B3 is met by achieving all of the following.
a. For defined periods, loadbearing elements of structure withstand the effects of fire without
loss of stability.
b. Compartmentation of buildings by fire resisting construction elements.
c. Automatic fire suppression is provided where it is necessary.
d. Protection of openings in fire-separating elements to maintain continuity of the fire separation.
e. Inhibition of the unseen spread of fire and smoke in cavities, in order to reduce the risk of
structural failure and spread of fire and smoke, where they pose a threat to the safety of people
in and around the building.
The extent to which any of these measures are necessary is dependent on the use of the building
and, in some cases, its size, and on the location of the elements of construction.
NOTES:
1.In assembly buildings (purpose group 5), a gallery is included as a storey, but not if it is a loading gallery, fly gallery, stage grid, lighting bridge, or any gallery provided for similar purposes, or for maintenance and repair.
2.In other purpose group buildings, galleries are not counted as a storey.
3.For the definition of basement, see Appendix A.
NOTES:
For single storey buildings, the periods under the heading ‘Up to 5’ apply. If single storey buildings have basements, for the basement storeys the period appropriate to their depth applies.
* For the floor over a basement or, if there is more than one basement, the floor over the topmost basement, the higher of the period for the basement storey and the period for the ground or upper storey applies.
† For compartment walls that separate buildings, the period is increased to a minimum of 60 minutes.
+ For any floor that does not contribute to the support of the building within a flat of more than one storey, the period is reduced to 30 minutes.
§ For flat conversions, refer to paragraphs 6.5 to 6.7 regarding the acceptability of 30 minutes.
‡ For elements that do not form part of the structural frame, the period is reduced to 90 minutes.
# For elements that protect the means of escape, the period is increased to 30 minutes.
1. Refer to note 1, Table B3 for the specific provisions of test.
2. Blocks of flats with a floor more than 30m above ground level should be fitted with a sprinkler system in accordance with Appendix E.
NOTE:
Sprinklers only need to be provided within the individual flats, they are not required in the common areas such as stairs, corridors or landings when these areas are fire sterile.
3.‘With sprinkler system’ means that the building is fitted throughout with an automatic sprinkler system in accordance with Appendix E.
4. Very large (over 18m in height or with a 10m deep basement) or unusual dwellinghouses are outside the scope of the guidance provided with regard to dwellinghouses.
5. A minimum of 30 minutes in the case of three storey dwellinghouses, increased to 60 minutes minimum for compartment walls separating buildings.
6. Buildings within the ‘office’, ‘shop and commercial’, ‘assembly and recreation’, ‘industrial’ and ‘storage and other non-residential’ (except car parks for light vehicles) purpose groups (purpose groups 3 to 7(a)) require sprinklers where there is a top storey above 30m.
The sprinkler system should be provided in accordance with Appendix E.
7. The car park should comply with the relevant provisions in the guidance on requirement B3, Section 11 of
Approved Document B Volume 2.
8. For the purposes of meeting the Building Regulations, the following types of steel elements are deemed to have satisfied the minimum period of fire resistance of 15 minutes when tested to the European test method.
i. Beams supporting concrete floors, maximum Hp/A=230m-1 operating under full design load.
ii. Free-standing columns, maximum Hp/A=180m-1 operating under full design load.
iii. Wind bracing and struts, maximum Hp/A=210m-1 operating under full design load.
Guidance is also available in BS EN 1993-1-2.
This section provides guidance on resisting fire spread over external walls; however, it does not deal with fire resistance of external walls. An external wall may need fire resistance to meet the provisions of Section 3 (Means of escape – flats), Section 6 (Loadbearing elements of structure – flats), Section 11 (Resisting fire spread from one building to another) or Section 15 (Access to buildings for firefighting personnel – flats).
A gallery should comply with one of the following.
a. It should be provided with an alternative exit.
b. It should be provided with an emergency escape window, as described in paragraph 2.10, where the gallery floor is a maximum of 4.5m above ground level.
c. It should meet all the conditions shown in Diagram 2.6.
NOTES:
1. This diagram does not apply where the gallery is provided with one of the following:
i. An alternative escape route
ii. An emergency escape window (where the gallery floor is not more than 4.5m above ground level).
2. Any cooking facilities within a room containing a gallery should comply with one of the following conditions:
i. Be enclosed with fire resisting construction
ii. Be remote from the stair to the gallery and positioned such that they do not prejudice escape from the gallery.
See para 2.15
NOTES:
1. This diagram does not apply where the gallery is provided with one of the following:
i. An alternative escape route
ii. An emergency escape window (where the gallery floor is not more than 4.5m above ground level).
2. Any cooking facilities within a room containing a gallery should comply with one of the following conditions:
i. Be enclosed with fire resisting construction
ii. Be remote from the stair to the gallery and positioned such that they do not prejudice escape from the gallery.
See para 3.13
A gallery should comply with one of the following.
a. It should be provided with an alternative exit.
b. It should be provided with an emergency escape window, as described in paragraph 3.6, where the gallery floor is a maximum of 4.5m above ground level.
c. It should meet the conditions shown in Diagram 3.1.
In buildings with more than three storeys above the ground storey, stairs may serve the flats and other occupancies if all of the following apply.
a. The flat is ancillary to the main use of the building.
b. The flat has an independent alternative escape route.
c. The stair is separated from occupancies on lower storeys by a protected lobby (minimum REI 30) at each of those storeys.
d. The stair enclosure has at least the same standard of fire resistance as the structural elements of the building (see Appendix B, Table B4); if the stair is a firefighting stair, it should comply with the provisions in Section 15 (see also paragraph 3.60).
e. Any automatic fire detection and alarm system fitted in the main part of the building also covers all flats.
f. Any security measures in any parts of the building do not prevent escape at all material times.
Elements of structure such as structural frames, beams, columns, loadbearing walls (internal and external), floor structures and gallery structures should have, as a minimum, the fire resistance given in Appendix B, Table B3.
If one element of structure supports or stabilises another, as a minimum the supporting element should have the same fire resistance as the other element.
The following are excluded from the definition of ‘element of structure’.
a. A structure that supports only a roof, unless either of the following applies.
i. The roof performs the function of a floor, such as a roof terrace, or as a means of escape.
ii. The structure is essential for the stability of an external wall that needs to be fire resisting (e.g. to achieve compartmentation or for the purposes of preventing fire spread between buildings).
b. The lowest floor of the building.
c. External walls, such as curtain walls or other forms of cladding, which transmit only self weight and wind loads and do not transmit floor load.
NOTE: In some cases, structural members within a roof may be essential for the structural stability system of the building. In these cases, the structural members in the roof do not just support a roof and must demonstrate the relevant fire resistance for the building as required by paragraph 5.2 above.
Elements of structure such as structural frames, beams, columns, loadbearing walls (internal and external), floor structures and gallery structures should have, as a minimum, the fire resistance given in Appendix B, Table B3.
NOTE: If one element of structure supports or stabilises another, as a minimum the supporting element should have the same fire resistance as the other element.
The following are excluded from the definition of ‘element of structure’.
a. A structure that supports only a roof, unless either of the following applies.
i. The roof performs the function of a floor, such as for parking vehicles, or as a means of escape.
ii. The structure is essential for the stability of an external wall that needs to be fire resisting (e.g. to achieve compartmentation or for the purposes of preventing fire spread between buildings).
b. The lowest floor of the building.
c. A platform floor.
d. External walls, such as curtain walls or other forms of cladding, which transmit only self weight and wind loads and do not transmit floor load.
NOTE: In some cases, structural members within a roof may be essential for the structural stability system of the building. In these cases, the structural members in the roof do not just support a roof and must demonstrate the relevant fire resistance for the building as required by the note to paragraph 6.1 above.
If a loadbearing wall is any of the following, guidance in other sections may also apply.
a. A compartment wall (including a wall common to two buildings): Section 7.
b. Enclosing a place of special fire hazard: Section 7.
c. Protecting a means of escape: Sections 2 and 3.
d. An external wall: Sections 10 and 11.
e. Enclosing a firefighting shaft: Section 15.
In a converted building with a maximum of three storeys, a minimum REI 30 fire resistance could be accepted for elements of structure if the means of escape conform to the provisions of Section 3.
NOTES:
1. The enclosure should meet all of the following conditions.
a. Be bounded by a compartment wall or floor, an outside wall, an intermediate floor or a casing(see specification at 2 below).
b. Have internal surfaces (except framing members)of class B-s3, d2 or better.
Note: when a classification includes ‘s3, d2’, this means that there is no limit set for smoke production and/or flaming droplets/particles).
c. Not have an access panel which opens into a circulation space or bed room.
d. Be used only for drainage or water supply or vent pipes for a drainage system.
2.The casing should meet all the following conditions.
a. Be imperforate except for an opening for a pipe
or an access panel.
b. Not be of sheet metal.
c. Not have fire resistance less than E 30 (including any access panel).
3.The opening for a pipe, in either the element of structure or the casing, should be as small as possible and fire-stopped around the pipe.
See para 9.4 and Table 9.1
Performance in terms of the fire resistance to be achieved by elements of structure, doors and
other forms of construction is classified in accordance with one of the following.
a. BS EN 13501-2.
b. BS EN 13501-3.
c. BS EN 13501-4.
The fire resistance necessary for different circumstances is set out in the following tables.
a. Table B3 gives the specific requirements for each element of structure.
b. Table B4 sets out the minimum periods of fire resistance for elements of structure.
c. Table B5 sets out limitations on the use of uninsulated fire resisting glazed elements.
The following guidance should be used when applying the fire resistance standards in Table B4.
a. If one element of structure supports or carries or gives stability to another, the fire resistance
of the supporting element should be no less than the minimum period of fire resistance for the
other element (whether that other element is loadbearing or not). In some circumstances, it
may be reasonable to vary this principle, for example:
i. if the supporting structure is in the open air and is not likely to be affected by the fire in
the building
ii. if the supporting structure is in a different compartment, with a fire-separating element
(that has the higher standard of fire resistance) between the supporting and the separated
structure
iii. if a plant room on the roof needs greater fire resistance than the elements of structure
that support it.
b. If an element of structure forms part of more than one building or compartment, that element
should be constructed to the standard of the higher of the relevant provisions.
c. If, due to the slope of the ground, one side of a basement is open at ground level (allowing
smoke to vent and providing access for firefighting) for elements of structure in that storey
it may be appropriate to adopt the standard of fire resistance that applies to above-ground
structures.
d. Although most elements of structure in a single storey building may not need fire resistance,
fire resistance is needed if one of the following applies to the element.
i. It is part of, or supports, an external wall, and there is provision in the guidance on
requirement B4 to limit the extent of openings and other unprotected areas in the wall.
ii. It is part of, or supports, a compartment wall, including a wall that is common to two or
more buildings.
iii. It supports a gallery.
The performance of some doorsets set out in Table C1 is linked to the minimum periods of fire resistance for elements of structure given in Tables B3 and B4. Limitations on the use of uninsulated glazing in fire doorsets are given in Table B5.
elevation
The following assumptions enable a reasonable standard of resistance to the spread of fire to be specified.
a. The size of a fire depends on the compartmentation within the building. A fire may involve a complete compartment, but will not spread to other compartments.
b. The intensity of a fire is related to the building use, but can be moderated by a sprinkler system.
c. Fires in ‘residential’ and ‘assembly and recreation’ buildings (purpose groups 1, 2 and 5) represent a greater risk to life.
d. A building on the far side of the relevant boundary meets both of the following conditions.
i. Has a similar elevation to the one in question.
ii. Is the same distance as the one in question from the common boundary.
e. The radiated heat passing through any part of the fire resisting external wall may be discounted.
For dwellinghouses, access for a pumping appliance should be provided to within 45m of all points inside the dwellinghouse. Every elevation to which vehicle access is provided should have a suitable door(s), not less than 750mm wide, giving access to the interior of the building.
For flats, either of the following provisions should be made.
a. Provide access for a pumping appliance to within 45m of all points inside each flat of a block, measured along the route of the hose. Every elevation to which vehicle access is provided should have a suitable door(s), not less than 750mm wide, giving access to the interior of the building. Door(s) should be provided such that there is no more than 60m between each door and/or the end of that elevation (e.g. a 150m elevation would need at least two doors).
b. Provide fire mains in accordance with paragraphs 13.5 and 13.6.
emergency lighting
The records should include details of all of the following.
e. All of the following.
i. Fire detector heads.
ii. Smoke detector heads.
iii. Alarm call points.
iv. Detection/alarm control boxes.
v. Alarm sounders.
vi. Emergency communications systems.
vii. CCTV.
viii. Fire safety signage.
ix. Emergency lighting.
x. Fire extinguishers.
xi. Dry or wet fire mains and other firefighting equipment.
xii. Other interior facilities for the fire and rescue service.
xiii. Emergency control rooms.
xiv. Location of hydrants outside the building.
xv. Other exterior facilities for the fire and rescue service.
In addition, escape lighting should be provided to all of the following.
a. Toilet accommodation with a minimum floor area of 8m2.
b. Electricity and generator rooms.
c. Switch room/battery room for emergency lighting system.
d. Emergency control rooms.
entrance storey
In buildings designed for phased evacuation or progressive horizontal evacuation, if the lift well is not within the enclosures of a protected stairway, its entrance should be separated at every storey by a protected lobby (minimum REI 30).
A multi-storey flat with an independent external entrance at ground level is similar to a dwellinghouse and means of escape should be planned on the basis of Section 2, depending on the height of the top storey above ground level.
When multi-storey flats do not have their own external entrance at ground level, adopt one of the following approaches.
a. Approach 1 – provide at least one alternative exit from each habitable room that is not on the entrance storey of the flat (Diagram 3.5 and paragraph 3.22).
b. Approach 2 – provide at least one alternative exit from each storey that is not the entrance storey of the flat. All habitable rooms should have direct access to a protected landing (Diagram 3.6 and paragraph 3.22).
Approach 3 – provide a protected stairway plus a sprinkler system in accordance with Appendix E (smoke alarms should also be provided in accordance with Section 1).
d. Approach 4 – if the vertical distance between the entrance storey of the flat and any of the storeys above or below does not exceed 7.5m, provide all of the following.
i. A protected stairway.
ii. Additional smoke alarms in all habitable rooms.
iii. A heat alarm in any kitchen.
equivalent area
Parts of walls in rooms may be of lower performance than stated in Table 4.1, but no worse than class D-s3, d2. In any one room, the total area of lower performance wall lining should be less than an area equivalent to half of the room’s floor area, up to a maximum of 20m2 of wall lining.
escape lighting
For flats serving as a workplace for both occupants and people who do not live on the premises, provide both of the following.
a. A maximum travel distance of 18m between any part of the working area and either of the following.
i. The flat entrance door.
ii. An alternative means of escape that is not a window.
If the travel distance is over 18m, the assumptions in paragraph 3.2 may not be valid. The design should be considered on a case-by-case basis.
b. Escape lighting to windowless accommodation in accordance with BS 5266-1.
Except for two storey blocks of flats, all escape routes should have adequate artificial lighting. If the mains electricity power supply fails, escape lighting should illuminate the route (including external escape routes).
In addition, escape lighting should be provided to all of the following.
a. Toilet accommodation with a minimum floor area of 8m2.
b. Electricity and generator rooms.
c. Switch room/battery room for emergency lighting system.
d. Emergency control rooms.
Escape stair lighting should be on a separate circuit from the electricity supply to any other part of the escape route.
Escape lighting should conform to BS 5266-1.
Single steps on escape routes should be prominently marked. A single step on the line of a doorway is acceptable, subject to paragraph 3.107.
All doors on escape routes should be hung to meet both of the following conditions.
a. Open by a minimum of 90 degrees.
b. Open with a swing that complies with both of the following.
i. Is clear of any change of floor level, other than a threshold or single step on the line of the doorway.
ii. Does not reduce the effective width of any escape route across a landing.
escape route
Flats
1. Within the enclosures of a protected entrance hall or protected landing, or within fire resisting separation shown in Section 3, Diagram 3.4.
2. Within either:
a. the enclosures of a protected stairway
b. fire resisting separation shown in Diagram 2.2.
3. Within fire resisting separation either:
a. shown in Diagram 2.4
b. described in paragraph 2.16b.
4. Existing window between an attached/integral garage and the dwellinghouse.
5. Adjacent to an external escape stair (see paragraph 2.17 and Diagram 2.7) or roof escape route (see paragraph 2.13).
6. Between residential/sleeping accommodation and a common escape route (corridor, lobby or stair).
7. Between a protected stairway(1)and either:
a. the accommodation
b. a corridor that is not a protected corridor other than in item 6 above.
8. Between either:
a. a protected stairway(1)and a protected lobby or protected corridor
b. accommodation and a protected lobby other than in item 6 above.
9. Between the accommodation and a protected corridor that forms a dead end,other than in item 6 above.
10.Between accommodation and any other corridor, or sub-dividing corridors,other than in item 6 above.
11. Beside an external escape route.
Table B5
see Table B3
Table B5
12. Beside an external escape stair (see paragraph 3.68 and Diagram 3.11) or roof escape route (see paragraph 3.30).
NOTES:
Items 1 and 8 apply also to single storey buildings.
Fire resisting glass should be marked with the name of the manufacturer and the name of the product.
Further guidance can be found in A Guide to Best Practice in the Specification and Use of Fire-resistant Glazed Systems published by the Glass and Glazing Federation.
1. If the protected stairway is also a protected shaft or a firefighting stair (see Section 15), there may be further
restrictions on the use of glazed elements.
2. Measured vertically from the landing floor level or the stair pitch line.
3. The 100mm limit is intended to reduce the risk of fire spreading from a floor covering.
Outlets should not be placed where they prevent the use of escape routes from the building.
Where a flat roof forms part of a means of escape, it should comply with all of the following.
a. It should be part of the same building from which escape is being made.
b. The route across the roof should lead to a storey exit or external escape route.
c. The part of the roof (including its supporting structure) forming the escape route, and any opening within 3m of the escape route, should be of fire resisting construction (minimum REI 30).
A balcony or flat roof intended to form part of an escape route should be provided with guarding etc. in accordance with Approved Document K.
Any external escape stair should meet all of the following conditions (Diagram 2.7).
a. Doors to the stair should be fire resisting (minimum E 30), except for a single exit door from the building to the top landing of a downward-leading external stair.
b. Fire resisting construction (minimum RE 30) is required for the building envelope within the following zones, measured from the flights and landings of the external stair.
i. 1800mm horizontally.
ii. 9m vertically below.
iii. 1100mm above the top landing of the stair (except where the stair leads from basement to ground level).
c. Fire resisting construction (minimum RE 30) should be provided for any part of the building (including doors) within 1800mm of the escape route from the foot of the stair to a place of safety. This does not apply if there are alternative escape routes from the foot of the external escape stair.
d. Stairs more than 6m in height should be protected from adverse weather. Protection should prevent the build-up of snow or ice but does not require full enclosure.
e. Glazing in areas of fire resisting construction should be fixed shut and fire resisting (in terms of integrity, but not insulation) (minimum E 30).
Where a new storey is added through conversion to create a storey above 4.5m, both of the following should apply.
a. The full extent of the escape route should be addressed.
b. Fire resisting doors (minimum E 20) and partitions (minimum REI 30) should be provided, including upgrading the existing doors where necessary.
NOTE: Where the layout is open plan, new partitions should be provided to enclose the escape route (Diagram 2.2).
See Diagram 2.1d. In addition to meeting the provisions in paragraph 2.5, the dwellinghouse should comply with either of the following.
a. Provide an alternative escape route from each storey more than 7.5m above ground level. At the first storey above 7.5m, the protected stairway should be separated from the lower storeys by fire resisting construction (minimum REI 30) if the alternative escape route is accessed via either of the following.
i. The protected stairway to an upper storey.
ii. A landing within the protected stairway enclosure to an alternative escape route on the same storey. The protected stairway at or about 7.5m above ground level should be separated from the lower storeys or levels by fire resisting construction (see Diagram 2.4).
b. Provide a sprinkler system throughout, designed and installed in accordance with BS 9251.
Where a flat roof forms part of a means of escape, it should comply with all of the following.
a. It should be part of the same building from which escape is being made.
b. The route across the roof should lead to a storey exit or external escape route.
c. The part of the roof (including its supporting structure) forming the escape route, and any opening within 3m of the escape route, should be of fire resisting construction (minimum REI 30).
A lift shaft serving storeys above ground level should not serve any basement, if either of the following applies.
a. There is only one escape stair serving storeys above ground level and smoke from a basement fire would adversely affect escape routes in the upper storeys.
b. The lift shaft is within the enclosure to an escape stair that terminates at ground level.
Final exits should not present a barrier for disabled people. Where the route to a final exit does not include stairs, a level threshold and, where necessary, a ramp should be provided.
Final exit locations should be clearly visible and recognisable.
A balcony or flat roof intended to form part of an escape route should be provided with guarding etc. in accordance with Approved Document K.
One of the following approaches should be adopted, observing the inner room restrictions described in paragraphs 3.7 and 3.8.
a. Provide a protected entrance hall (minimum REI 30) serving all habitable rooms that meets the conditions shown in Diagram 3.2.
b. Plan the flat to meet the conditions shown in Diagram 3.3, so that both of the following apply.
i. The travel distance from the flat entrance door to any point in any habitable room is a maximum of 9m.
ii. Cooking facilities are remote from the main entrance door and do not impede the escape route from anywhere in the flat.
c. Provide an alternative exit from the flat complying with paragraph 3.19.
Any alternative exit from a flat should comply with all of the following.
a. It should be remote from the main entrance door to the flat.
b. It should lead to a final exit, via a common stair if necessary, through one of the following.
i. A door to an access corridor, access lobby or common balcony.
ii. An internal private stair leading to an access corridor, access lobby or common balcony at another level.
iii. A door to a common stair.
iv. A door to an external stair.
v. A door to an escape route over a flat roof.
Any access route leading to a final exit or common stair should comply with the provisions for means of escape in the common parts of a flat (see paragraph 3.25).
A person escaping through the common area, if confronted by the effects of a fire in another flat, should be able to turn away from it and make a safe escape via an alternative route.
From the flat entrance door, a single escape route is acceptable in either of the following cases.
a. The flat is on a storey served by a single common stair and both of the following apply.
i. Every flat is separated from the common stair by a protected lobby or common protected corridor (see Diagram 3.7).
ii. The maximum travel distance in Table 3.1, for escape in one direction only, is not exceeded.
b. The flat is in a dead end of a common corridor served by two (or more) common stairs and the maximum travel distance given in Table 3.1, for escape in one direction only, is not exceeded (Diagram 3.8).
Provisions are recommended to support a stay put evacuation strategy for blocks of flats. It is based on the principle that a fire is contained in the flat of origin and common escape routes are maintained relatively free from smoke and heat. It allows occupants, some of whom may require assistance to escape in the event of a fire, in other flats that are not affected to remain.
Sufficient protection to common means of escape is necessary to allow occupants to escape should they choose to do so or are instructed/aided to by the fire service. A higher standard of protection is therefore needed to ensure common escape routes remain available for a longer period than is provided in other buildings.
Where a storey or part of a building has multiple escape routes available, one may be over a flat roof that complies with all of the following.
a. It should be part of the same building from which escape is being made.
b. The route across the roof should lead to a storey exit or external escape route.
c. The part of the roof (including its supporting structure) forming the escape route, and any opening within 3m of the escape route, should be of fire resisting construction (minimum REI 30).
d. The route should be clearly defined and guarded by walls and/or protective barriers to protect against falling.
Where a storey or part of a building has multiple escape routes available, one may be over a flat roof that complies with all of the following.
d. The route should be clearly defined and guarded by walls and/or protective barriers to protect against falling.
Escape route travel distances should comply with Table 3.1.
An escape route should not pass through one stair enclosure to reach another. It may pass through a protected lobby (minimum REI 30) of one stair to reach another.
Ancillary accommodation should not be located in, or entered from, a protected lobby or protected corridor forming the only common escape route on that storey.
Escape routes should have a minimum clear headroom of 2m. The only projections allowed below this height are door frames.
Escape route floor finishes should minimise their slipperiness when wet. Finishes include the treads of steps and surfaces of ramps and landings.
A ramp forming part of an escape route should meet the provisions in Approved Document M. Any sloping floor or tier should have a pitch of not more than 35 degrees to the horizontal.
Except for two storey blocks of flats, all escape routes should have adequate artificial lighting. If the mains electricity power supply fails, escape lighting should illuminate the route (including external escape routes).
Escape stair lighting should be on a separate circuit from the electricity supply to any other part of the escape route.
Access openings to refuse storage chambers should not be sited in the following areas.
a. Next to escape routes or final exits.
b. Near the windows of flats.
Where more than one escape route is available from a storey (or part of a building), then some of the escape routes from that storey or part of the building may be by way of an external stair provided all of the following conditions are met:
a. There is a at least one internal escape stair from every part of each storey (excluding plant areas).
b. The stair serves a floor not more than 6m above either the ground level or a roof podium which is itself served by an independent protected stairway.
c. The stair meets the provisions in paragraph 3.68.
Any external escape stair should meet all of the following conditions (Diagram 3.11).
a. Doors to the stair should be fire resisting (minimum E 30) and be fitted with a self-closing device, except for a single exit door from the building to the top landing of a downward-leading external stair, provided it is the only door onto the landing.
b. Fire resisting construction (minimum RE 30) is required for the building envelope within the following zones, measured from the flights and landings of the external stair.
i. 1800mm above and horizontally.
ii. 9m vertically below.
iii. 1100mm above the top landing of the stair (except where the stair leads from basement to ground level).
c. Fire resisting construction (minimum RE 30) should be provided for any part of the building (including doors) within 1800mm of the escape route from the foot of the stair to a place of safety. This does not apply if there are alternative escape routes from the foot of the external escape stair.
d. Glazing in areas of fire resisting construction should be fixed shut and fire resisting (in terms of integrity but not insulation) (minimum E 30).
e. Stairs more than 6m in height above ground level (e.g. where they are provided above a podium) should be protected from adverse weather. Protection should prevent the build-up of snow or ice but does not require full enclosure.
If a building does not meet the criteria of paragraph 3.28, an escape stair forming part of the only escape route from an upper storey should not continue down to serve a basement storey. The basement storey should be served by a separate escape stair.
Except in buildings described in paragraph 3.28, common stairs forming part of the only escape route from a flat should not serve any of the following.
a. Covered car park.
b. Boiler room.
c. Fuel storage space.
d. Other ancillary accommodation of similar fire risk.
Where a common stair is not part of the only escape route from a flat, it may also serve ancillary accommodation from which it is separated by a protected lobby or protected corridor (minimum REI 30).
Single steps on escape routes should be prominently marked. A single step on the line of a doorway is acceptable, subject to paragraph 3.107.
Doors should be readily openable to avoid undue delay to people escaping. Doors on escape routes (both within and from the building) should comply with paragraphs 3.91 to 3.98. Guidance on door closing and ‘hold open’ devices for fire doorsets is set out in Appendix C.
NOTE: Paragraphs 3.91 to 3.98 do not apply to flat entrance doors.
In general, doors on escape routes (whether or not the doors are fire doorsets) should be either of the following.
a. Not fitted with a lock, latch or bolt fastenings.
b. Fitted only with simple fastenings that are all of the following.
i. Easy to operate; it should be apparent how to undo the fastening.
ii. Operable from the side approached by people escaping.
iii. Operable without a key.
iv. Operable without requiring people to manipulate more than one mechanism.
Doors may be fitted with hardware to allow them to be locked when rooms are empty.
If a secure door is operated by code or combination keypad, swipe or proximity card, biometric data, etc., a security mechanism override should be possible from the side approached by people escaping.
Electrically powered locks should return to the unlocked position in all of the following situations.
a. If the fire detection and alarm system operates.
b. If there is loss of power or system error.
c. If the security mechanism override is activated.
Security mechanism overrides for electrically powered locks should be a Type A call point, as described in BS 7273-4. The call point should be positioned on the side approached by people escaping. If the door provides escape in either direction, a call point should be installed on both sides of the door.
The door of any doorway or exit should be hung to open in the direction of escape whenever reasonably practicable. It should always be hung to open in the direction of escape if more than 60 people might be expected to use it during a fire.
All doors on escape routes should be hung to meet both of the following conditions.
a. Open by a minimum of 90 degrees.
b. Open with a swing that complies with both of the following.
i. Is clear of any change of floor level, other than a threshold or single step on the line of the doorway.
ii. Does not reduce the effective width of any escape route across a landing.
If the fire resisting construction of a protected escape route is either of the following.
a. Not carried to full storey height.
b. At the top storey, not carried to the underside of the roof covering.
Then the cavity above or below the fire resisting construction should be either of the following.
i. Fitted with cavity barriers on the line of the enclosure.
ii. For cavities above the fire resisting construction, enclosed on the lower side by a fire resisting ceiling (minimum EI 30) that extends throughout the building, compartment or separated part (see Diagram 8.3).
In divided corridors (paragraph 3.25 and following) with cavities, fire-stopping should be provided to prevent alternative escape routes being affected by fire and/or smoke.
Method 1 should not be used for extract ductwork passing through the enclosures of protected escape routes (Diagrams 9.3 and 9.4), as large volumes of smoke can pass thermal devices without triggering them.
An ES classified fire and smoke damper which is activated by a suitable fire detection system (method 4) may also be used for protected escape routes.
NOTE:
Ventilation ducts which serve other parts of the building should not supply or extract air directly to or from a protected escape route.
Ductwork enclosed in fire resisting construction classified EI X in accordance with BSEN13501-2 (fire exposure from the duct side), or fire resisting ductwork classified EIS X in accordance with BS EN 13501-3, where X is the fire resistance rating (in minutes) of the walls of the protected escape route
See para 9.16
ES leakage rated fire and smoke damper conforming to BS EN 13501-3/BS EN 1366-2
Smoke detection system in accordance with BS 5839-1 to activate ES damper
Ductwork passing through protected escape routes–method 4
NOTE:
Ventilation ducts which serve other parts of the building should not supply or extract air directly to or from a protected escape route.
See para 9.16
A fire and smoke damper should be provided where ductwork enters or leaves each section of the protected escape route it serves. It should be operated by a smoke detector or suitable fire detection system. Fire and smoke dampers should close when smoke is detected. Alternatively, the methods set out in paragraphs 9.16 and 9.17 and Diagrams 9.3 and 9.4 may be followed.
Width is measured according to the following.
a. For a door (or doorway), the clear width when the door is open (Diagram D1).
b. For an escape route, either of the following.
i. When the route is defined by walls: the width at 1500mm above finished floor level.
ii. Elsewhere: the minimum width of passage available between any fixed obstructions.
c. For a stair, the clear width between the walls or balustrades. On escape routes and stairs,
handrails and strings intruding into the width by a maximum of 100mm on each side may be
ignored. Rails used for guiding a stair-lift may be ignored, but it should be possible to park the
lift’s chair or carriage in a position that does not obstruct the stair or landing.
evacuation lift
A lift well connecting different compartments should form a protected shaft (see Section 7).
In buildings designed for phased evacuation or progressive horizontal evacuation, if the lift well is not within the enclosures of a protected stairway, its entrance should be separated at every storey by a protected lobby (minimum REI 30).
In basements and enclosed car parks, the lift should be within the enclosure of a protected stairway. Otherwise, the lift should be approached only via a protected lobby or protected corridor (minimum REI 30).
Lift machine rooms should be sited over the lift well where possible. Where buildings or part of a building with only one stairway make this arrangement impractical, the lift machine room should be sited outside the protected stairway.
exempt buildings and work
Regulations 5(k) and 6(3) provide that, where the use of a building is changed such that the building becomes a building described in regulation 7(4), the construction of the external walls, and specified attachments, must be investigated and, where necessary, work must be carried out to ensure they only contain materials achieving class A2-s1, d0 or class A1, other than those exempted by regulation 7(3).
Where both of the following apply, separation distances may be determined from the wall rather than from the edge of the canopy (Diagram 11.6).
a. The canopy is attached to the side of a building.
b. The edges of the canopy are a minimum of 2m from the relevant boundary.
Canopies that fall within class 6 or class 7 of Schedule 2 to the regulations (Exempt Buildings and Work) are exempt from the Building Regulations.
exit passageway
A lift well connecting different compartments should form a protected shaft (see Section 7).
In buildings designed for phased evacuation or progressive horizontal evacuation, if the lift well is not within the enclosures of a protected stairway, its entrance should be separated at every storey by a protected lobby (minimum REI 30).
In basements and enclosed car parks, the lift should be within the enclosure of a protected stairway. Otherwise, the lift should be approached only via a protected lobby or protected corridor (minimum REI 30).
If a lift delivers into a protected corridor or protected lobby serving sleeping accommodation and also serves a storey containing a high fire risk (such as a kitchen, communal areas, stores, etc.) then the lift should be separated from the high fire risk area(s) by a protected lobby or protected corridor (minimum REI 30).
Final exits should not present a barrier for disabled people. Where the route to a final exit does not include stairs, a level threshold and, where necessary, a ramp should be provided.
Final exit locations should be clearly visible and recognisable.
Final exits should avoid outlets of basement smoke vents and openings to transformer chambers, refuse chambers, boiler rooms and similar risks.
The construction separating two adjacent protected stairways (or exit passageways leading to different final exits) should be imperforate.
Every protected stairway should lead to a final exit, either directly or via a protected exit passageway. Any protected exit corridor or stair should have the same standard of fire resistance and lobby protection as the stair it serves.
external wall
External fire spread
B4.(1)The external walls of the building shall adequately resist the spread of fire over the walls and from one building to another, having regard to the height, use and position of the building.
(2)The roof of the building shall adequately resist the spread of fire over the roof and from one building to another, having regard to the use and position of the building.
Regulation 7 – Materials and workmanship
(1)Building work shall be carried out—
(a)with adequate and proper materials which—
(i)are appropriate for the circumstances in which they are used,
(ii)are adequately mixed or prepared, and
(iii)are applied, used or fixed so as adequately to perform the functions for which they are designed; and
(b)in a workmanlike manner.
(2)Subject to paragraph (3), building work shall be carried out so that materials which become part of an external wall, or specified attachment, of a relevant building are of European Classification A2-s1, d0 or A1, classified in accordance with BS EN 13501-1:2007+A1:2009 entitled “Fire classification of construction products and building elements. Classification using test data from reaction to fire tests” (ISBN 978 0 580 59861 6) published by the British Standards Institution on 30th March 2007 and amended in November 2009.
(3)Paragraph (2) does not apply to—
(a)cavity trays when used between two leaves of masonry;
(b)any part of a roof (other than any part of a roof which falls within paragraph (iv) of regulation 2(6))if that part is connected to an external wall;
(c)door frames and doors;
(d)electrical installations;
(e)insulation and water proofing materials used below ground level;
(f)intumescent and fire stopping materials where the inclusion of the materials is necessary to meet the requirements of Part B of Schedule 1;
(g)membranes;
(h)seals, gaskets, fixings, sealants and backer rods;
(i)thermal break materials where the inclusion of the materials is necessary to meet the thermal bridging requirements of Part L of Schedule 1; or
(j)window frames and glass.
(4)In this regulation—
(a)a “relevant building” means a building with a storey (not including roof-top plant areas or any storey consisting exclusively of plant rooms) at least 18 metres above ground level and which—
(i)contains one or more dwellings;
(ii)contains an institution; or
(iii)contains a room for residential purposes(excluding any room in a hostel, hotel or boarding house); and
(b)“above ground level” in relation to a storey means above ground level when measured from the lowest ground level adjoining the outside of a building to the top of the floor surface of the storey.
The external envelope of a building should not contribute to undue fire spread from one part of a
building to another part. This intention can be met by constructing external walls so that both of
the following are satisfied.
a. The risk of ignition by an external source to the outside surface of the building and spread of
fire over the outside surface is restricted.
b. The materials used to construct external walls, and attachments to them, and how they are
assembled do not contribute to the rate of fire spread up the outside of the building.
The extent to which this is necessary depends on the height and use of the building.
Table 10.1 Reaction to fire performance of external surface of walls
‘Relevant buildings’ as defined in regulation 7(4) (see paragraph 10.10)
NOTES:
In addition to the requirements within this table, buildings with a top occupied storey above 18m should also meet the provisions of paragraph 10.6.
In all cases, the advice in paragraph 10.4 should be followed.
1. The restrictions for these buildings apply to all the materials used in the external wall and specified attachments (see paragraphs 10.9 to 10.12 for further guidance).
2. Profiled or flat steel sheet at least 0.5 mm thick with an organic coating of no more than 0.2mm thickness is also acceptable.
3. Timber cladding at least 9mm thick is also acceptable.
4. 10m is measured from the top surface of the roof.
The external wall of a building should not provide a medium for fire spread if that is likely to be a risk to health and safety. Combustible materials and cavities in external walls and attachments to them can present such a risk, particularly in tall buildings. The guidance in this section is designed to reduce the risk of fire spread as well as the risk of ignition from flames coming from adjacent buildings.
External walls and specified attachments are defined in regulation 2(6) and these definitions
include any parts of the external wall as well as balconies, solar panels and solar shading.
Regulation 7(3) provides an exemption for certain components found in external walls and specified attachments.
This section provides guidance on resisting fire spread over external walls; however, it does not deal with fire resistance of external walls. An external wall may need fire resistance to meet the provisions of Section 3 (Means of escape – flats), Section 6 (Loadbearing elements of structure – flats), Section 11 (Resisting fire spread from one building to another) or Section 15 (Access to buildings for firefighting personnel – flats).
The provisions of regulation 7 apply in addition to requirement B4. Therefore, for buildings described in regulation 7(4), the potential impact of any products incorporated into or onto the external walls and specified attachments should be carefully considered with regard to their number, size, orientation and position.
Particular attention is drawn to the following points.
a. Membranes used as part of the external wall construction above ground level should achieve a minimum of class B-s3, d0. Roofing membranes do not need to achieve a minimum of class A2-s1, d0 when used as part of a roof connecting to an external wall.
b. Internal linings should comply with the guidance provided in Section 4.
c. Any part of a roof should achieve the minimum performance as detailed in Section 12.
d. As per regulation 7(3), window frames and glass (including laminated glass) are exempted
from regulation 7(2). Window spandrel panels and infill panels must comply with regulation 7(2).
e. Thermal breaks are small elements used as part of the external wall construction to restrict
thermal bridging. There is no minimum performance for these materials. However, they
should not span two compartments and should be limited in size to the minimum required
to restrict the thermal bridging (the principal insulation layer is not to be regarded as a
thermal break).
f. Regulation 7(2) only applies to specified attachments. Shop front signs and similar attachments are
not covered by the requirements of regulation 7(2), although attention is drawn to paragraph 10.21g.
g. While regulation 7(2) applies to materials which become part of an external wall or specified
attachment, consideration should be given to other attachments to the wall which could
impact on the risk of fire spread over the wall.
h. Any material achieving class A1fl or A2fl-s1 in accordance with BS EN 13501-1 is exempted when it
meets both of the following conditions.
i. It forms the top horizontal floor layer of a balcony.
ii. It is provided with an imperforate substrate under it which extends to the full size of the
class A1fl or A2fl-s1 material.
The external walls of buildings other than those described in regulation 7(4) of the Building Regulations should achieve either of the following.
a. Follow the provisions given in paragraphs 10.5 to 10.9, which provide guidance on all of the following.
i. External surfaces.
ii. Materials and products.
iii. Cavities and cavity barriers..
b. Meet the performance criteria given in BRE report BR 135 for external walls using full-scale test data from BS 8414-1 or BS 8414-2.
Exclude external walls of stairways in a protected shaft when assessing unprotected areas (see Diagram 11.5).
The unprotected area of the external wall of a stairway forming a protected shaft may be disregarded for separation distance purposes
Roofs pitched at an angle of less than 70 degrees may be disregarded for separation distance purposes
Represents an unprotected area of not more than 1m2 which may consist of two or more smaller areas within an area of 1000mm X 1000mm
Represents an area of not more than 0.1m2
See para 11.11
Parts of an external wall with less fire resistance than the appropriate amount given in Appendix B, Table B4, are called unprotected areas.
Where a fire resisting external wall has an external surface material that is worse than class B-s3, d2 and is more than 1mm thick, that part of the wall should be classified as an unprotected area equating to half its area (Diagram 11.4).
The external envelope of a building should not provide a medium for fire spread if it is likely to be a risk to health or safety. The use of combustible materials for cladding framework, or of combustible thermal insulation as an overcladding or in ventilated cavities, may present such a risk in tall buildings, even though the provisions for external surfaces in Diagram 40 may have been satisfied.
In a building with a storey 18m or more above ground level, insulation material used in ventilated cavities in the external wall construction should be of limited combustibility (see Appendix A). This restriction does not apply to masonry cavity wall construction which complies with Diagram 32 in Section 10. Advice on the use of thermal insulation material is given in the BRE Report Fire performance of external thermal insulation for walls of multi-storey buildings (BR 135, 1988).
Each basement space should have one or more smoke outlets.
Where this is not practicable (for example, the plan area is deep and the amount of external wall is restricted by adjoining buildings), the perimeter basement spaces may be vented, with other spaces vented indirectly by opening connecting doors. This does not apply for places of special fire hazard (see paragraph 16.7).
If a basement is compartmented, each compartment should have one or more smoke outlets, rather than indirect venting.
A basement storey or compartment containing rooms with doors or windows does not need smoke outlets.
Configurations of stairs and external wall
Fire resisting construction
Fire resisting construction of adjacent building enclosure of protected stairway
Non-fire resisting construction
See para 3.63
With some configurations of external wall, a fire in one part of a building could subject the external wall of a protected stairway to heat (for example, where the two are adjacent at an internal angle in the façade, as shown in Diagram 3.10).
If a protected stairway projects beyond, is recessed from or is in an internal angle of the adjoining external wall of the building, then the minimum distance between an unprotected area of the building enclosure and an unprotected area of the stair enclosure should be 1800mm.
See paras 3.27 and 3.36
NOTES:
1. The arrangements shown also apply to the top storey.
2. See Diagram 3.9 for small single stair buildings.
3. All doors shown are fire doorsets.
4. Where travel distance is measured to a stair lobby, the lobby must not provide direct access to any storage room, flat or other space containing a potential fire hazard.
5. For further guidance on the fire rating of the fire doorsets from the corridor to the flat and/or stairway refer to Appendix C ,Table C1.
F Flat
Shaded areas indicate zones where ventilation should be provided in accordance with paragraphs 3.50 to 3.53(An external wall vent or smoke shaft located anywhere in the shaded area)
See paras 3.27 and 3.36
NOTES:
1. The arrangements shown also apply to the top storey.
2. See Diagram 3.9 for small single stair buildings.
3. All doors shown are fire doorsets.
4. Where travel distance is measured to a stair lobby, the lobby must not provide direct access to any storage room, flat or other space containing a potential fire hazard.
5. For further guidance on the fire rating of the fire doorsets from the corridor to the flat and/or stairway refer to Appendix C ,Table C1.
F Flat
Shaded areas indicate zones where ventilation should be provided in accordance with paragraphs 3.50 to 3.53(An external wall vent or smoke shaft located anywhere in the shaded area)
a. CORRIDOR ACCESS WITHOUT DEAD ENDS
b. CORRIDOR ACCESS WITH DEAD ENDS
The central door may be omitted if maximum travel distance is not more than 15m.
1. The arrangements shown also apply to the top storey.
2. For further guidance on the fire rating of the fire doorsets from the corridor to the flat and/or stairway refer to Appendix C ,Table C1.
Fire doorset provided in accordance with paragraphs 3.50 to 3.53(An external wall vent or smoke shaft located anywhere in the shaded area)
See paras 3.27 and 3.36
All doors on escape routes should be hung to meet both of the following conditions.
a. Open by a minimum of 90 degrees.
b. Open with a swing that complies with both of the following.
i. Is clear of any change of floor level, other than a threshold or single step on the line of the doorway.
ii. Does not reduce the effective width of any escape route across a landing.
The following are excluded from the definition of ‘element of structure’.
a. A structure that supports only a roof, unless either of the following applies.
i. The roof performs the function of a floor, such as a roof terrace, or as a means of escape.
ii. The structure is essential for the stability of an external wall that needs to be fire resisting (e.g. to achieve compartmentation or for the purposes of preventing fire spread between buildings).
b. The lowest floor of the building.
c. External walls, such as curtain walls or other forms of cladding, which transmit only self weight and wind loads and do not transmit floor load.
NOTE: In some cases, structural members within a roof may be essential for the structural stability system of the building. In these cases, the structural members in the roof do not just support a roof and must demonstrate the relevant fire resistance for the building as required by paragraph 5.2 above.
The following are excluded from the definition of ‘element of structure’.
a. A structure that supports only a roof, unless either of the following applies.
i. The roof performs the function of a floor, such as for parking vehicles, or as a means of escape.
ii. The structure is essential for the stability of an external wall that needs to be fire resisting (e.g. to achieve compartmentation or for the purposes of preventing fire spread between buildings).
b. The lowest floor of the building.
c. A platform floor.
d. External walls, such as curtain walls or other forms of cladding, which transmit only self weight and wind loads and do not transmit floor load.
NOTE: In some cases, structural members within a roof may be essential for the structural stability system of the building. In these cases, the structural members in the roof do not just support a roof and must demonstrate the relevant fire resistance for the building as required by the note to paragraph 6.1 above.
The diagram shows three common examples which illustrate the principles. The elements enclosing the shaft (unless formed by adjacent external walls) are compartment walls and floors.
The shaft structure (including any openings) should meet the relevant provisions for: compartment walls (see paragraphs 7.5 to7.19), external walls (see sections 10 and 11 and Diagram 3.10).
See para 7.23
The external wall of a protected shaft does not normally need to have fire resistance. Situations where there are provisions are given in paragraph 3.63 (external walls of protected stairways, which may also be protected shafts) and paragraphs 15.8 to 15.11 (firefighting shafts).
Openings in other parts of the enclosure to a protected shaft should be limited to the following.
a. If a wall common to two or more buildings forms part of the enclosure, only the following openings should be made in that wall.
i. A fire doorset providing a means of escape, which has the same fire resistance as the wall and is fitted in accordance with the provisions in Appendix C.
ii. The passage of a pipe that meets the provisions in Section 9.
b. Other parts of the enclosure (other than an external wall) should only have openings for any of the following.
i. Fire doorsets of the appropriate fire resistance, fitted in accordance with the provisions in Appendix C.
ii. The passage of pipes which meet the provisions in Section 9.
iii. Inlets to, outlets from and openings for a ventilation duct (if the shaft contains or serves as a ventilating duct), meeting the provisions in Section 9.
iv. The passage of lift cables into a lift machine room (if the shaft contains a lift). If the machine room is at the bottom of the shaft, the openings should be as small as practicable.
extract ventilation
NOTE:
Ventilation ducts which serve other parts of the building should not supply or extract air directly to or from a protected escape route.
Ductwork enclosed in fire resisting construction classified EI X in accordance with BSEN13501-2 (fire exposure from the duct side), or fire resisting ductwork classified EIS X in accordance with BS EN 13501-3, where X is the fire resistance rating (in minutes) of the walls of the protected escape route
See para 9.16
ES leakage rated fire and smoke damper conforming to BS EN 13501-3/BS EN 1366-2
Smoke detection system in accordance with BS 5839-1 to activate ES damper
Ductwork passing through protected escape routes–method 4
NOTE:
Ventilation ducts which serve other parts of the building should not supply or extract air directly to or from a protected escape route.
See para 9.16
Ventilation ducts supplying or extracting air directly to or from a protected stairway should not also serve other areas. A separate ventilation system should be provided for each protected stairway.
factory-made metal chimneys (also known as system chimneys)
Fire mains are installed for the fire and rescue service to connect hoses for water. They may be either of the following.
a. The ‘dry’ type, which are both of the following.
i. Normally kept empty.
ii. Supplied through a hose from a fire and rescue service pumping appliance.
b. The ‘wet’ type, which are both of the following.
i. Kept full of water.
ii. Supplied by pumps from tanks in the building.
There should be a facility to replenish a wet system from a pumping appliance in an emergency.
NOTES:
1. Any metal (such as cast iron, copper or steel) which, if exposed to a temperature of 800°C, will not soften or fracture to the extent that flame or hot gas will pass through the wall of the pipe.
2. uPVC pipes that comply with either BS 4514 or BS 5255.
3. These diameters are only in relation to pipes that form part of an above-ground drainage system and are enclosed as shown in Diagram 9.1. In other cases, the maximum diameters given for situation 5 apply.
A pipe with a maximum nominal internal diameter of 160mm may be used with a sleeve made out of a high melting point metal, as shown in Diagram 9.2, if the pipe is made of one of the following.
a. Lead.
b. Aluminium.
c. Aluminium alloy.
d. Fibre-cement.
e. uPVC (pipes should also comply with either BS 4514 or BS 5255).
A high melting point metal means any metal (such as cast iron, copper or steel) which, if exposed to a temperature of 800°C, will not soften or fracture to the extent that flame or hot gas will pass through the wall of the pipe.
Any test evidence used to demonstrate the fire performance classification of a product or system should be carefully checked to ensure that it is applicable to the intended use. Small differences in detail, such as fixing method, joints, dimensions, the introduction of insulation materials and air gaps (ventilated or not), can significantly affect the performance.
final certificate
Glazed elements should also comply with the following, where necessary.
a. If the enclosure forms part of a protected shaft: Section 7.
b. Appendix B, Table B5.
c. Guidance on the safety of glazing: Approved Document K.
final exit
BS 476-11
BS 476-7
NOTE:
The national classifications do not automatically equate with the transposed classifications in the ‘BS EN 13501-1 classification’ column, therefore products cannot typically assume a European class unless they have been tested accordingly.
NOTE:
A classification of s3, d2 indicates that no limit is set for production of smoke and/or flaming droplets/particles. If a performance for production of smoke and/or flaming droplets/ particles is specified, then only the European classes can be used. For example, a national class may not be used as an alternative to a classification which includes s1, d0.
Where a complex mix of uses exists, the effect that one use may have on another in terms of risk should be considered. It could be necessary to use guidance from both volumes, apply other guidance (such as from HTM 05-02 or Building Bulletin 100), and/or apply special measures to reduce the risk.
Smoke alarms should be mains operated and conform to BS EN 14604.
Heat and smoke from basement fires vented via stairs can inhibit access for firefighting personnel. This may be reduced by providing smoke outlets, or smoke vents, which allow heat and smoke to escape from the basement levels to the open air. They can also be used by the fire and rescue service to let cooler air into the basements (Diagram 16.1).
Outlets should not be placed where they prevent the use of escape routes from the building.
Natural smoke outlet shafts should be separated from each other using construction of class A1 rating and fire resistance at least equal to that of the storeys they serve, where the shafts are either of the following.
a. From different compartments of the same basement storey.
b. From different basement storeys.
Smoke outlets connecting directly to the open air should be provided from every basement storey, except for any basement storey that has both of the following.
a. A maximum floor area of 200m2.
b. A floor a maximum of 3m below the adjacent ground level.
See Diagram 2.1c. The dwellinghouse should have either of the following. Cavity barriers or a fire resisting ceiling (minimum EI 30) should be provided above a protected stairway enclosure (Diagram 2.3). b. Alternative escape route – a top storey separated from lower storeys by fire resisting construction (minimum REI 30) and with an alternative escape route leading to its own final exit.
a. Protected stairway – a stair separated by fire resisting construction (minimum REI 30) at all storeys, that complies with one of the following.
i. Extends to a final exit (Diagram 2.2a).
ii. Gives access to a minimum of two ground level final exits that are separated from each other by fire resisting construction (minimum REI 30) and fire doorsets (minimum E 20) (Diagram 2.2b).
People should be able to rapidly leave the area around the building. Direct access to a street, passageway, walkway or open space should be available. The route away from the building should comply with the following.
a. Be well defined.
b. If necessary, have suitable guarding.
Final exits should not present a barrier for disabled people. Where the route to a final exit does not include stairs, a level threshold and, where necessary, a ramp should be provided.
Final exit locations should be clearly visible and recognisable.
Final exits should avoid outlets of basement smoke vents and openings to transformer chambers, refuse chambers, boiler rooms and similar risks.
Any alternative exit from a flat should comply with all of the following.
a. It should be remote from the main entrance door to the flat.
b. It should lead to a final exit, via a common stair if necessary, through one of the following.
i. A door to an access corridor, access lobby or common balcony.
ii. An internal private stair leading to an access corridor, access lobby or common balcony at another level.
iii. A door to a common stair.
iv. A door to an external stair.
v. A door to an escape route over a flat roof.
Any access route leading to a final exit or common stair should comply with the provisions for means of escape in the common parts of a flat (see paragraph 3.25).
The following paragraphs deal with means of escape from the entrance doors of
flats to a final exit. They do not apply to flats with a top storey that is a maximum
of 4.5m above ground level (designed in accordance with paragraphs 3.15 to 3.17).
Reference should also be made to the following.
a. Requirement B3 regarding compartment walls and protected shafts.
b. Requirement B5 regarding access for the fire and rescue service.
A person escaping through the common area, if confronted by the effects of a fire in another flat, should be able to turn away from it and make a safe escape via an alternative route.
Provisions are recommended to support a stay put evacuation strategy for blocks of flats. It is based on the principle that a fire is contained in the flat of origin and common escape routes are maintained relatively free from smoke and heat. It allows occupants, some of whom may require assistance to escape in the event of a fire, in other flats that are not affected to remain.
Sufficient protection to common means of escape is necessary to allow occupants to escape should they choose to do so or are instructed/aided to by the fire service. A higher standard of protection is therefore needed to ensure common escape routes remain available for a longer period than is provided in other buildings.
The following paragraphs deal with means of escape from the entrance doors of flats to a final exit.
The construction separating two adjacent protected stairways (or exit passageways leading to different final exits) should be imperforate.
Where a stair serves an enclosed car park or place of special fire hazard, the lobby or corridor should have a minimum 0.4m2 of permanent ventilation or be protected from the ingress of smoke by a mechanical smoke control system.
NOTE: For refuse chutes and storage see paragraphs 3.55 to 3.58.
Every protected stairway should lead to a final exit, either directly or via a protected exit passageway. Any protected exit corridor or stair should have the same standard of fire resistance and lobby protection as the stair it serves.
The door of any doorway or exit should be hung to open in the direction of escape whenever reasonably practicable. It should always be hung to open in the direction of escape if more than 60 people might be expected to use it during a fire.
Cavities in the construction of a building provide a ready route for the spread of smoke and flame, which can present a greater danger as any spread is concealed. For the purpose of this document, a cavity is considered to be any concealed space.
Cavities in the construction of a building provide a ready route for the spread of smoke and flame, which can present a greater danger as any spread is concealed. For the purpose of this document, a cavity is considered to be any concealed space.
Ductwork should not help to transfer fire and smoke through the building. Terminals of exhaust points should be sited away from final exits, cladding or roofing materials achieving class B-s3, d2 or worse and openings into the building.
A fire and smoke damper should be provided where ductwork enters or leaves each section of the protected escape route it serves. It should be operated by a smoke detector or suitable fire detection system. Fire and smoke dampers should close when smoke is detected. Alternatively, the methods set out in paragraphs 9.16 and 9.17 and Diagrams 9.3 and 9.4 may be followed.
fire alarm system
All dwellings should have a fire detection and alarm system, minimum Grade D2 Category LD3
standard, in accordance with the relevant recommendations of BS 5839-6.
A higher standard of protection should be considered where occupants of a proposed dwelling
would be at special risk from fire. Further advice on this is also given in BS 5839-6.
Each flat in a block should have alarms as set out in paragraphs 1.1 to 1.4. With effective compartmentation, a communal fire alarm system is not normally needed. In some buildings, detectors in common parts of the building may need to operate smoke control or other fire protection systems but do not usually sound an audible warning.
The fire detection and alarm systems in flats should connect to a central monitoring point or alarm
receiving centre. The systems should alert the warden or supervisor and identify the individual flat
where a fire has been detected.
Fire detection and alarm systems must be properly designed, installed and maintained. A design,
installation and commissioning certificate should be provided for fire detection and alarm systems.
Third party certification schemes for fire protection products and related services are an effective
means of providing assurances of quality, reliability and safety.
Fire detection and alarm systems sometimes trigger other systems. The interface between systems
must be reliable. Particular care should be taken if the interface is facilitated via another system.
Where any part of BS 7273 applies to the triggering of other systems, the recommendations of that
part of BS 7273 should be followed.
Smoke and heat alarms should have a standby power supply, such as a battery (rechargeable
or non-rechargeable) or capacitor. More information on power supplies is given in clause 15 of
BS 5839-6.
NOTE: The term ‘fire alarm system’ describes the combination of components for giving an audible
and/or other perceptible warning of fire.
NOTE: In this document, the term ‘fire detection system’ describes any type of automatic sensor
network and associated control and indicating equipment. Sensors may be sensitive to smoke,
heat, gaseous combustion products or radiation. Automatic sprinkler systems can also be used to
operate a fire alarm system.
A large dwellinghouse of two storeys (excluding basement storeys) should be fitted with a Grade A
Category LD3 fire detection and alarm system, as described in BS 5839-6.
A large dwellinghouse of three or more storeys (excluding basement storeys) should be fitted with
a Grade A Category LD2 fire detection and alarm system as described in BS 5839-6.
A fire detection and alarm system should be installed where either of the
following applies.
a. A new habitable room is provided above or below the ground storey.
b. A new habitable room is provided at the ground storey, without a final exit.
Regulation 7(2) applies to any building with a storey at least 18m above ground level (as
measured in accordance with Diagram D6 in Appendix D) and which contains one or more
dwellings; an institution; or a room for residential purposes. It requires that all materials which become part of an external wall or specified attachment achieve class A2-s1, d0 or class A1 in accordance with BS EN 13501-1, other than those exempted by regulation 7(3).
NOTE: The above includes student accommodation, care homes, sheltered housing, hospitals, dormitories in boarding schools, hotels, hostels and boarding houses. See regulation 7(4) for the definition of relevant buildings.
NOTE: Transposition to national class (Table B1) does not apply to the classification in this paragraph.
In buildings with more than three storeys above the ground storey, stairs may serve the flats and other occupancies if all of the following apply.
a. The flat is ancillary to the main use of the building.
b. The flat has an independent alternative escape route.
c. The stair is separated from occupancies on lower storeys by a protected lobby (minimum REI 30) at each of those storeys.
d. The stair enclosure has at least the same standard of fire resistance as the structural elements of the building (see Appendix B, Table B4); if the stair is a firefighting stair, it should comply with the provisions in Section 15 (see also paragraph 3.60).
e. Any automatic fire detection and alarm system fitted in the main part of the building also covers all flats.
f. Any security measures in any parts of the building do not prevent escape at all material times.
Materials used for fire-stopping should be reinforced with (or supported by) materials rated class A2-s3, d2 or better to prevent displacement in both of the following cases.
a. Where the unsupported span is greater than 100mm.
b. Where non-rigid materials are used (unless subjected to appropriate fire resistance testing to show their suitability).
Proprietary, tested fire-stopping and sealing systems are available and may be used. Different materials suit different situations and not all are suitable in every situation.
If a self-closing device would be considered to interfere with the normal approved use of the
building, self-closing fire doors may be held open by one of the following.
a. A fusible link, but not if the doorset is in an opening provided as a means of escape unless it
complies with paragraph C7.
b. An automatic release mechanism activated by an automatic fire detection and alarm system.
c. A door closer delay device.
Rolling shutters should be capable of manual opening and closing for firefighting purposes (see Section 15). Rolling shutters across a means of escape should only be released by a heat sensor, such as a fusible link or electric heat detector, in the immediate vicinity of the door. Unless a shutter is also intended to partially descend as part of a boundary to a smoke reservoir, shutters across a means of escape should not be closed by smoke detectors or a fire alarm system.
fire and smoke damper
Smoke vents should comply with one of the following.
a. They should be located on an external wall with minimum free area of 1.5m2.
b. They should discharge into a vertical smoke shaft, closed at the base, that meets all of the following criteria.
i. The shaft should conform to the following conditions.
• Have a minimum cross-sectional area of 1.5m2 (minimum dimension 0.85m in any direction).
• Open at roof level, minimum 0.5m above any surrounding structures within 2m of it horizontally.
• Extend a minimum of 2.5m above the ceiling of the highest storey served by the shaft.
ii. The free area of all the following vents should be a minimum of 1m2 in the following places.
• From the corridor or lobby into the shaft.
• At the opening at the head of the shaft.
• At all internal locations within the shaft (e.g. safety grilles).
iii. The smoke shaft should be constructed from a class A1 material. All vents should either be a smoke leakage (Sa) rated fire doorset (see Appendix C, Table C1, item 2.e for minimum fire resistance) or fitted with a smoke control damper achieving the same period of fire resistance and designed to operate as described below. The shaft should be vertical from base to head, with a maximum of 4m at a maximum inclined angle of 30 degrees.
iv. If smoke is detected in the common corridor or lobby, both of the following should occur.
• Simultaneous opening of vents on the storey where the fire is located, at the top of the smoke shaft and to the stair.
• Vents from the corridors or lobbies on all other storeys should remain closed, even if smoke is subsequently detected on storeys other than where the fire is located.
Fire resistance test criteria are set out in Appendix C. Standards of performance are summarised in Table C1.
If air handling ducts pass through fire-separating elements, the fire performance of the elements should be maintained using one or more of the following four methods. In most ductwork systems, a combination of the four methods is best.
a. Method 1 – thermally activated fire dampers.
b. Method 2 – fire resisting enclosures.
c. Method 3 – protection using fire resisting ductwork.
d. Method 4 – automatically activated fire and smoke dampers triggered by smoke detectors.
Where ducts pass between fire-separating elements to serve multiple flats or dwellings, fire dampers or fire and smoke dampers should be actuated by both of the following.
a. Smoke detector-controlled automatic release mechanisms.
b. Thermally actuated devices.
An ES classified fire and smoke damper which is activated by a suitable fire detection system (method 4) may also be used for protected escape routes.
Both fire dampers and fire and smoke dampers should be all of the following.
a. Sited within the thickness of the fire-separating elements.
b. Securely fixed.
c. Sited such that, in a fire, expansion of the ductwork would not push the fire damper through the structure.
Fire and smoke dampers should meet both of the following conditions.
a. Conform to BS EN 15650.
b. Have a minimum ES classification of 60 minutes or to match the integrity rating of the fire resisting elements, whichever is higher.
Smoke detectors should be sited so as to prevent the spread of smoke as early as practicable by activating the fire and smoke dampers. Smoke detectors and automatic release mechanisms used to activate fire dampers and/or fire and smoke dampers should conform to BS EN 54-7 and BS 5839-3 respectively.
Further information on fire dampers and/or fire and smoke dampers is given in the ASFP Grey Book.
In addition to any other provisions in this section, both of the following conditions should be met.
a. Joints between fire-separating elements should be fire-stopped.
b. Openings through a fire resisting element for pipes, ducts, conduits or cable should be all of the following.
i. As few as possible.
ii. As small as practicable.
iii. Fire-stopped (allowing thermal movement in the case of a pipe or duct).
NOTE: The fire-stopping around fire dampers, fire resisting ducts, fire and smoke dampers and smoke control ducts should be in accordance with the manufacturer or supplier’s installation instructions.
ES leakage rated fire and smoke damper conforming to BS EN 13501-3/BS EN 1366-2
Smoke detection system in accordance with BS 5839-1 to activate ES damper
Ductwork passing through protected escape routes–method 4
NOTE:
Ventilation ducts which serve other parts of the building should not supply or extract air directly to or from a protected escape route.
See para 9.16
A fire and smoke damper should be provided where ductwork enters or leaves each section of the protected escape route it serves. It should be operated by a smoke detector or suitable fire detection system. Fire and smoke dampers should close when smoke is detected. Alternatively, the methods set out in paragraphs 9.16 and 9.17 and Diagrams 9.3 and 9.4 may be followed.
fire compartment
Height of top storey measured from upper floor surface of top floor to ground level on lowest side of building
Height of top storey excludes roof-top plant areas and any top storeys consisting exclusively of plant rooms
Where a building or compartment has more than one use, it is appropriate to assign each different use to its own purpose group in the following situations.
a. If the ancillary use is a flat.
b. If both of the following apply.
i. The building or compartment has an area of more than 280m2.
ii. The ancillary use relates to an area that is more than one-fifth of the total floor area of the building or compartment.
c. In ‘shop and commercial’ (purpose group 4) buildings or compartments, if the ancillary use is storage and both of the following apply.
i. The building or compartment has an area of more than 280m2.
ii. The storage area comprises more than one-third of the total floor area of the building or compartment.
A large dwellinghouse of two storeys (excluding basement storeys) should be fitted with a Grade A
Category LD3 fire detection and alarm system, as described in BS 5839-6.
A large dwellinghouse of three or more storeys (excluding basement storeys) should be fitted with
a Grade A Category LD2 fire detection and alarm system as described in BS 5839-6.
Table 10.1 Reaction to fire performance of external surface of walls
‘Relevant buildings’ as defined in regulation 7(4) (see paragraph 10.10)
NOTES:
In addition to the requirements within this table, buildings with a top occupied storey above 18m should also meet the provisions of paragraph 10.6.
In all cases, the advice in paragraph 10.4 should be followed.
1. The restrictions for these buildings apply to all the materials used in the external wall and specified attachments (see paragraphs 10.9 to 10.12 for further guidance).
2. Profiled or flat steel sheet at least 0.5 mm thick with an organic coating of no more than 0.2mm thickness is also acceptable.
3. Timber cladding at least 9mm thick is also acceptable.
4. 10m is measured from the top surface of the roof.
The following assumptions enable a reasonable standard of resistance to the spread of fire to be specified.
a. The size of a fire depends on the compartmentation within the building. A fire may involve a complete compartment, but will not spread to other compartments.
b. The intensity of a fire is related to the building use, but can be moderated by a sprinkler system.
c. Fires in ‘residential’ and ‘assembly and recreation’ buildings (purpose groups 1, 2 and 5) represent a greater risk to life.
d. A building on the far side of the relevant boundary meets both of the following conditions.
i. Has a similar elevation to the one in question.
ii. Is the same distance as the one in question from the common boundary.
e. The radiated heat passing through any part of the fire resisting external wall may be discounted.
Buildings with a storey more than 50m above fire service vehicle access level should be provided with wet fire mains. In all other buildings where fire mains are provided, either wet or dry fire mains are suitable.
Fire service vehicle access to fire mains should be provided as described in paragraphs 13.5 and 13.6.
A building requires additional fire hydrants if both of the following apply.
a. It has a compartment with an area of more than 280m2.
b. It is being erected more than 100m from an existing fire hydrant.
To assist the fire service to identify each floor in a block of flats with a top storey more than 11m above ground level (see Diagram D6), floor identification signs and flat indicator signs should be provided.
In blocks of flats (purpose group 1(a)) with a top storey over 18m above ground level (see Diagram D6 in Appendix D) an evacuation alert system should be provided in accordance with BS 8629.
Buildings in which firefighting shafts should be provided,
showing which storeys need to be served >18m >10m
a. Any building The upper storeys in any building with a storey more than 18m above fire service vehicle access level
b. Any building The basement storeys in any building with a basement more than 10m below fire service vehicle access level
c. Any building The basement storey(s) in any building with two or more basements each exceeding 900m2
Fire service vehicle access level
Two or more basement storeys each exceeding 900m2
Extent of firefighting Extent of firefighting lift stair
NOTES:
1.Height excludes any top storey(s) consisting exclusively of plant rooms.
2.Firefighting shafts should serve all floors through which they pass.
See para 15.2
In buildings where a firefighting shaft is required, a minimum of two firefighting shafts should be provided in either of the following situations.
a. A building that has both of the following.
i. A storey with a floor area of 900m2 or more.
ii. A storey 18m or more above the fire and rescue service vehicle access level.
b. A building with a basement storey which is more than 900m2.
Firefighting shafts and protected stairways should be positioned such that every part of each storey more than 18m above the fire and rescue service vehicle access level complies with the maximum distances given in paragraph 15.7. Distances should be measured from the fire main outlet on a route suitable for laying a hose.
NOTE: If the internal layout is not known, the distance should be measured at two-thirds of the direct distance.
Natural smoke outlet shafts should be separated from each other using construction of class A1 rating and fire resistance at least equal to that of the storeys they serve, where the shafts are either of the following.
a. From different compartments of the same basement storey.
b. From different basement storeys.
Each basement space should have one or more smoke outlets.
Where this is not practicable (for example, the plan area is deep and the amount of external wall is restricted by adjoining buildings), the perimeter basement spaces may be vented, with other spaces vented indirectly by opening connecting doors. This does not apply for places of special fire hazard (see paragraph 16.7).
If a basement is compartmented, each compartment should have one or more smoke outlets, rather than indirect venting.
A basement storey or compartment containing rooms with doors or windows does not need smoke outlets.
Basic information on the location of fire protection measures may be sufficient. An as-built plan of the building should be provided showing all of the following.
a. Escape routes – this should include exit capacity (i.e. the maximum allowable number of people for each storey and for the building).
b. Location of fire-separating elements (including cavity barriers in walk-in spaces).
c. Fire doorsets, fire doorsets fitted with a self-closing device and other doors equipped with relevant hardware.
d. Locations of fire and/or smoke detector heads, alarm call points, detection/alarm control boxes, alarm sounders, fire safety signage, emergency lighting, fire extinguishers, dry or wet fire mains and other firefighting equipment, and hydrants outside the building.
e. Any sprinkler systems, including isolating valves and control equipment.
f. Any smoke control systems, or ventilation systems with a smoke control function, including mode of operation and control systems.
g. Any high risk areas (e.g. heating machinery).
The records should include details of all of the following.
d. All passive fire safety measures, including all of the following.
i. Compartmentation (i.e. location of fire-separating elements).
ii. Cavity barriers.
iii. Fire doorsets, including fire doorsets fitted with a self-closing device and other doors equipped with relevant hardware (e.g. electronic security locks).
iv. Duct dampers.
v. Fire shutters.
Fire resisting window(minimum RE30)
No fire resistance required for door
1100mm zone above top landing
6m max. height without weather protection
1800mm zone of fire resisting construction at side of stairway
Fire doorset(minimum E30)
See para 2.17
The following paragraphs deal with means of escape from the entrance doors of
flats to a final exit. They do not apply to flats with a top storey that is a maximum
of 4.5m above ground level (designed in accordance with paragraphs 3.15 to 3.17).
Reference should also be made to the following.
a. Requirement B3 regarding compartment walls and protected shafts.
b. Requirement B5 regarding access for the fire and rescue service.
Common corridors should be protected corridors. The wall between each flat and the corridor should be a compartment wall (minimum REI 30 where the top storey is up to 5m above ground level, otherwise REI 60).
Refuse chutes and rooms for storing refuse should meet both of the following conditions.
a. Be separated from other parts of the building by fire resisting construction (minimum REI 30 in buildings with a top storey up to 5m above ground level; otherwise REI 60).
b. Not be situated within a protected stairway or protected lobby.
See para 3.21
NOTE: This only applies where at least one storey is more than 4.5m above ground level.
Fire doorset
Fire resisting stair enclosure(minimum REI 30)
Alternative exit
See paras 3.27 and 3.36
NOTES:
1. The arrangements shown also apply to the top storey.
2. See Diagram 3.9 for small single stair buildings.
3. All doors shown are fire doorsets.
4. Where travel distance is measured to a stair lobby, the lobby must not provide direct access to any storage room, flat or other space containing a potential fire hazard.
5. For further guidance on the fire rating of the fire doorsets from the corridor to the flat and/or stairway refer to Appendix C ,Table C1.
F Flat
Shaded areas indicate zones where ventilation should be provided in accordance with paragraphs 3.50 to 3.53(An external wall vent or smoke shaft located anywhere in the shaded area)
See paras 3.27 and 3.36
NOTES:
1. The arrangements shown also apply to the top storey.
2. See Diagram 3.9 for small single stair buildings.
3. All doors shown are fire doorsets.
4. Where travel distance is measured to a stair lobby, the lobby must not provide direct access to any storage room, flat or other space containing a potential fire hazard.
5. For further guidance on the fire rating of the fire doorsets from the corridor to the flat and/or stairway refer to Appendix C ,Table C1.
F Flat
Shaded areas indicate zones where ventilation should be provided in accordance with paragraphs 3.50 to 3.53(An external wall vent or smoke shaft located anywhere in the shaded area)
a. CORRIDOR ACCESS WITHOUT DEAD ENDS
b. CORRIDOR ACCESS WITH DEAD ENDS
The central door may be omitted if maximum travel distance is not more than 15m.
1. The arrangements shown also apply to the top storey.
2. For further guidance on the fire rating of the fire doorsets from the corridor to the flat and/or stairway refer to Appendix C ,Table C1.
Fire doorset provided in accordance with paragraphs 3.50 to 3.53(An external wall vent or smoke shaft located anywhere in the shaded area)
See paras 3.27 and 3.36
To reduce the risk of fire spreading over the roof from one compartment to another, a 1500mm wide zone of the roof, either side of the wall, should have a covering classified as BROOF(t4), on a substrate or deck of a material rated class A2-s3, d2 or better, as set out in Diagram 5.2a.
Thermoplastic rooflights that, because of paragraph 12.7, are regarded as having a BROOF(t4) classification are not suitable for use in that zone.
Cavity barriers should be provided at all of the following locations.
a. At the edges of cavities, including around openings (such as windows, doors and exit/entry points for services).
b. At the junction between an external cavity wall and every compartment floor and compartment wall.
c. At the junction between an internal cavity wall and every compartment floor, compartment wall or other wall or door assembly forming a fire resisting barrier.
This does not apply where a wall meets the conditions of Diagram 5.3.
It is not appropriate to complete a line of compartment walls by fitting cavity barriers above them. The compartment wall should be extended to the underside of the floor or roof above.
Where adding an additional storey to a two storey single family dwellinghouse, new floors should have a minimum REI 30 fire resistance. Any floor forming part of the enclosure to the circulation space between the loft conversion and the final exit should achieve a minimum rating of REI 30.
The existing first-storey construction should have a minimum rating of R 30. The fire performance may be reduced for integrity and insulation, when both of the following conditions are met.
a. Only one storey is added, containing a maximum of two habitable rooms.
b. The new storey has a maximum total area of 50m2.
All compartment walls and compartment floors should achieve both of the following.
a. Form a complete barrier to fire between the compartments they separate.
b. Have the appropriate fire resistance, as given in Appendix B, Table B3 and Table B4.
Timber beams, joists, purlins and rafters may be built into or carried through a masonry or concrete compartment wall if the openings for them are both of the following.
a. As small as practicable.
b. Fire-stopped.
If trussed rafters bridge the wall, failure of the truss due to a fire in one compartment should not cause failure of the truss in another compartment.
If a loadbearing wall is any of the following, guidance in other sections may also apply.
a. A compartment wall (including a wall common to two buildings): Section 7.
b. Enclosing a place of special fire hazard: Section 7.
c. Protecting a means of escape: Sections 2 and 3.
d. An external wall: Sections 10 and 11.
e. Enclosing a firefighting shaft: Section 15.
In a converted building with four or more storeys, the full standard of fire resistance given in Appendix B is necessary.
All of the following should be provided as compartment walls and compartment floors and should have, as a minimum, the fire resistance given in Appendix B, Table B3.
a. Any floor (unless it is within a flat, i.e. between one storey and another within one individual dwelling).
b. Any wall separating a flat from another part of the building.
c. Any wall enclosing a refuse storage chamber.
d. Any wall common to two or more buildings.
Compartment walls not described in paragraphs 7.8 and 7.9 should run the full height of the storey in which they are situated.
Compartment walls in a top storey beneath a roof should be continued through the roof space.
At the junction with another compartment wall or an external wall, the fire resistance of the compartmentation should be maintained. Fire-stopping that meets the provisions in paragraphs 9.24 to 9.29 should be provided.
At the junction of a compartment floor and an external wall with no fire resistance, the external wall should be restrained at floor level. The restraint should reduce movement of the wall away from the floor if exposed to fire.
Compartment walls should be able to accommodate deflection of the floor, when exposed to fire, by either of the following means.
a. Between the wall and floor, provide a head detail that is capable of maintaining its integrity while deforming.
b. Design the wall so it maintains its integrity by resisting the additional vertical load from the floor above.
Where compartment walls are located within the middle half of a floor between vertical supports, the deflection may be assumed to be 40mm unless a smaller value can be justified by assessment. Outside this area, the limit can be reduced linearly to zero at the supports.
For steel beams that do not have the required fire resistance, reference should be made to SCI Publication P288.
Stairs and service shafts connecting compartments should be protected to restrict the spread of fire between the compartments. These are called protected shafts. Walls or floors surrounding a protected shaft are considered to be compartment walls or compartment floors.
The construction enclosing a protected shaft (Diagram 7.1) should do all of the following.
a. Form a complete barrier to fire between the compartments connected by the shaft.
b. Have the appropriate fire resistance given in Appendix B, Table B3, except for uninsulated glazed screens that meet the provisions of paragraph 7.24.
c. Satisfy the provisions for ventilation and the treatment of openings in paragraphs 7.28 and 7.29.
All compartment walls and compartment floors should achieve both of the following.
a. Form a complete barrier to fire between the compartments they separate.
b. Have the appropriate fire resistance, as given in Appendix B, Tables B3 and B4.
Timber beams, joists, purlins and rafters may be built into or carried through a masonry or concrete compartment wall if the openings for them are both of the following.
a. As small as practicable.
b. Fire-stopped.
If trussed rafters bridge the wall, failure of the truss due to a fire in one compartment should not cause failure of the truss in another compartment.
Where services could provide a source of ignition, the risk of fire developing and spreading into adjacent compartments should be controlled.
Cavity barriers should be provided at all of the following locations.
a. At the edges of cavities, including around openings (such as windows, doors and exit/entry points for services).
b. At the junction between an external cavity wall and every compartment floor and compartment wall.
c. At the junction between an internal cavity wall and every compartment floor, compartment wall or other wall or door assembly forming a fire resisting barrier.
This does not apply where a wall meets the conditions of Diagram 8.2.
It is not appropriate to complete a line of compartment walls by fitting cavity barriers above them. The compartment walls should extend to the underside of the floor or roof above.
If the fire resisting construction of a protected escape route is either of the following.
a. Not carried to full storey height.
b. At the top storey, not carried to the underside of the roof covering.
Then the cavity above or below the fire resisting construction should be either of the following.
i. Fitted with cavity barriers on the line of the enclosure.
ii. For cavities above the fire resisting construction, enclosed on the lower side by a fire resisting ceiling (minimum EI 30) that extends throughout the building, compartment or separated part (see Diagram 8.3).
Smoke detectors should be sited so as to prevent the spread of smoke as early as practicable by activating the fire and smoke dampers. Smoke detectors and automatic release mechanisms used to activate fire dampers and/or fire and smoke dampers should conform to BS EN 54-7 and BS 5839-3 respectively.
Further information on fire dampers and/or fire and smoke dampers is given in the ASFP Grey Book.
The wall of a flue, duct containing flues or appliance ventilation duct(s) should have a fire resistance (REI) that is at least half of any compartment wall or compartment floor it passes through or is built into (Diagram 9.5).
a. Flue passing through compartment wall or floor
b. Flue built into compartment wall
Flue walls should have a fire resistance of at least one half of that required for the compartment wall or floor and be of class A1construction.
In each case flue walls should have a fire resistance of at least one half of that required for the compartment wall and be of class A1 construction.
See para 9.23
The following guidance should be used when applying the fire resistance standards in Table B4.
a. If one element of structure supports or carries or gives stability to another, the fire resistance
of the supporting element should be no less than the minimum period of fire resistance for the
other element (whether that other element is loadbearing or not). In some circumstances, it
may be reasonable to vary this principle, for example:
i. if the supporting structure is in the open air and is not likely to be affected by the fire in
the building
ii. if the supporting structure is in a different compartment, with a fire-separating element
(that has the higher standard of fire resistance) between the supporting and the separated
structure
iii. if a plant room on the roof needs greater fire resistance than the elements of structure
that support it.
b. If an element of structure forms part of more than one building or compartment, that element
should be constructed to the standard of the higher of the relevant provisions.
c. If, due to the slope of the ground, one side of a basement is open at ground level (allowing
smoke to vent and providing access for firefighting) for elements of structure in that storey
it may be appropriate to adopt the standard of fire resistance that applies to above-ground
structures.
d. Although most elements of structure in a single storey building may not need fire resistance,
fire resistance is needed if one of the following applies to the element.
i. It is part of, or supports, an external wall, and there is provision in the guidance on
requirement B4 to limit the extent of openings and other unprotected areas in the wall.
ii. It is part of, or supports, a compartment wall, including a wall that is common to two or
more buildings.
iii. It supports a gallery.
For the purposes of this paragraph, the ground storey of a building that has one or more basement storeys and no upper storeys may be considered as a single storey building. The fire resistance of the basement storeys should be that specified for basements.
fire damper
see Table B4
See Table C1
See Appendix C
NOTES:
1. BS EN 13501-2 Classification using data from fire resistance tests, excluding ventilation services.BS EN 13501-3
Classification using data from fire resistance tests on products and elements used in building service installations: fire resisting ducts and fire dampers. BS EN 13501-4 Classification using data from fire resistance tests on components of smoke control systems.
In the European classification:
‘R’ is the resistance to fire in terms of loadbearing capacity.
‘E’ is the resistance to fire in terms of integrity.
‘I’ is the resistance to fire in terms of insulation.
The national classifications do not automatically equate with the alternative classifications in the European column, therefore products cannot typically assume a European class unless they have been tested accordingly.
2. BS 476-20 for general principles,BS 476-21 for loadbearing elements,BS 476-22 for non-loadbearing elements,BS 476-23 for fire-protecting suspended ceilings and BS 476-24 for ventilation ducts.
3. Applies to loadbearing elements only (see paragraph B19).
4. Guidance on increasing the fire resistance of existing timber floors is given in BRE Digest 208.
5. Only if a suspended ceiling meets the appropriate provisions should it be relied on to add to the fire resistance of the floor.
6. Such walls may contain areas that do not need to be fire resisting (unprotected areas). See Section 11.
7. Unless needed as part of a wall in item 5a or 5b.
8. Except for any limitations on uninsulated glazed elements given in Table B5.
Smoke vents should comply with one of the following.
a. They should be located on an external wall with minimum free area of 1.5m2.
b. They should discharge into a vertical smoke shaft, closed at the base, that meets all of the following criteria.
i. The shaft should conform to the following conditions.
• Have a minimum cross-sectional area of 1.5m2 (minimum dimension 0.85m in any direction).
• Open at roof level, minimum 0.5m above any surrounding structures within 2m of it horizontally.
• Extend a minimum of 2.5m above the ceiling of the highest storey served by the shaft.
ii. The free area of all the following vents should be a minimum of 1m2 in the following places.
• From the corridor or lobby into the shaft.
• At the opening at the head of the shaft.
• At all internal locations within the shaft (e.g. safety grilles).
iii. The smoke shaft should be constructed from a class A1 material. All vents should either be a smoke leakage (Sa) rated fire doorset (see Appendix C, Table C1, item 2.e for minimum fire resistance) or fitted with a smoke control damper achieving the same period of fire resistance and designed to operate as described below. The shaft should be vertical from base to head, with a maximum of 4m at a maximum inclined angle of 30 degrees.
iv. If smoke is detected in the common corridor or lobby, both of the following should occur.
• Simultaneous opening of vents on the storey where the fire is located, at the top of the smoke shaft and to the stair.
• Vents from the corridors or lobbies on all other storeys should remain closed, even if smoke is subsequently detected on storeys other than where the fire is located.
Guidance on door closing and ‘hold open’ devices for fire doorsets is set out in Appendix C.
Openings should be limited to the following.
a. Fire doorsets with a minimum E 30 rating, fitted in accordance with Appendix C.
b. The passage of pipes that follow the provisions in Section 9.
c. The passage of cables or conduits containing one or more cables.
d. Openings fitted with a suitably mounted and appropriate fire damper.
e. Ducts that are either of the following.
i. Fire resisting (minimum E 30).
ii. Fitted with a suitably mounted and appropriate fire damper where they pass through the cavity barrier.
NOTE: For further guidance on openings in cavity barriers see Section 9.
If air handling ducts pass through fire-separating elements, the fire performance of the elements should be maintained using one or more of the following four methods. In most ductwork systems, a combination of the four methods is best.
a. Method 1 – thermally activated fire dampers.
b. Method 2 – fire resisting enclosures.
c. Method 3 – protection using fire resisting ductwork.
d. Method 4 – automatically activated fire and smoke dampers triggered by smoke detectors.
Where ducts pass between fire-separating elements to serve multiple flats or dwellings, fire dampers or fire and smoke dampers should be actuated by both of the following.
a. Smoke detector-controlled automatic release mechanisms.
b. Thermally actuated devices.
An ES classified fire and smoke damper which is activated by a suitable fire detection system (method 4) may also be used for protected escape routes.
Both fire dampers and fire and smoke dampers should be all of the following.
a. Sited within the thickness of the fire-separating elements.
b. Securely fixed.
c. Sited such that, in a fire, expansion of the ductwork would not push the fire damper through the structure.
Access to the fire damper and its actuating mechanism should be provided for inspection, testing and maintenance.
Fire dampers should meet both of the following conditions.
a. Conform to BS EN 15650.
b. Have a minimum E classification of 60 minutes or to match the integrity rating of the fire resisting elements, whichever is higher.
Fire and smoke dampers should meet both of the following conditions.
a. Conform to BS EN 15650.
b. Have a minimum ES classification of 60 minutes or to match the integrity rating of the fire resisting elements, whichever is higher.
Smoke detectors should be sited so as to prevent the spread of smoke as early as practicable by activating the fire and smoke dampers. Smoke detectors and automatic release mechanisms used to activate fire dampers and/or fire and smoke dampers should conform to BS EN 54-7 and BS 5839-3 respectively.
Further information on fire dampers and/or fire and smoke dampers is given in the ASFP Grey Book.
In addition to any other provisions in this section, both of the following conditions should be met.
a. Joints between fire-separating elements should be fire-stopped.
b. Openings through a fire resisting element for pipes, ducts, conduits or cable should be all of the following.
i. As few as possible.
ii. As small as practicable.
iii. Fire-stopped (allowing thermal movement in the case of a pipe or duct).
NOTE: The fire-stopping around fire dampers, fire resisting ducts, fire and smoke dampers and smoke control ducts should be in accordance with the manufacturer or supplier’s installation instructions.
ES leakage rated fire and smoke damper conforming to BS EN 13501-3/BS EN 1366-2
Smoke detection system in accordance with BS 5839-1 to activate ES damper
Ductwork passing through protected escape routes–method 4
NOTE:
Ventilation ducts which serve other parts of the building should not supply or extract air directly to or from a protected escape route.
See para 9.16
A fire and smoke damper should be provided where ductwork enters or leaves each section of the protected escape route it serves. It should be operated by a smoke detector or suitable fire detection system. Fire and smoke dampers should close when smoke is detected. Alternatively, the methods set out in paragraphs 9.16 and 9.17 and Diagrams 9.3 and 9.4 may be followed.
fire doorset
Basic information on the location of fire protection measures may be sufficient. An as-built plan of the building should be provided showing all of the following.
a. Escape routes – this should include exit capacity (i.e. the maximum allowable number of people for each storey and for the building).
b. Location of fire-separating elements (including cavity barriers in walk-in spaces).
c. Fire doorsets, fire doorsets fitted with a self-closing device and other doors equipped with relevant hardware.
d. Locations of fire and/or smoke detector heads, alarm call points, detection/alarm control boxes, alarm sounders, fire safety signage, emergency lighting, fire extinguishers, dry or wet fire mains and other firefighting equipment, and hydrants outside the building.
e. Any sprinkler systems, including isolating valves and control equipment.
f. Any smoke control systems, or ventilation systems with a smoke control function, including mode of operation and control systems.
g. Any high risk areas (e.g. heating machinery).
The records should include details of all of the following. d. All passive fire safety measures, including all of the following. e. All of the following.
a. The fire safety strategy, including all assumptions in the design of the fire safety systems (such as fire load). Any risk assessments or risk analysis.
b. All assumptions in the design of the fire safety arrangements for the management of the building.
c. All of the following.
i. Escape routes (including occupant load and capacity of escape routes).
ii. Any provision to enable the evacuation of disabled people.
iii. Escape strategy (e.g. simultaneous or phased).
iv. Muster points.
i. Compartmentation (i.e. location of fire-separating elements).
ii. Cavity barriers.
iii. Fire doorsets, including fire doorsets fitted with a self-closing device and other doors equipped with relevant hardware (e.g. electronic security locks).
iv. Duct dampers.
v. Fire shutters.
i. Fire detector heads.
ii. Smoke detector heads.
iii. Alarm call points.
iv. Detection/alarm control boxes.
v. Alarm sounders.
vi. Emergency communications systems.
vii. CCTV.
viii. Fire safety signage.
ix. Emergency lighting.
x. Fire extinguishers.
xi. Dry or wet fire mains and other firefighting equipment.
xii. Other interior facilities for the fire and rescue service.
xiii. Emergency control rooms.
xiv. Location of hydrants outside the building.
xv. Other exterior facilities for the fire and rescue service.
f. All active fire safety measures, including both of the following.
i. Sprinkler system(s) design, including isolating valves and control equipment.
ii. Smoke control system(s) (or heating, ventilation and air conditioning system with a smoke control function) design, including mode of operation and control systems.
g. Any high risk areas (e.g. heating machinery) and particular hazards.
h. Plans of the building as built, showing the locations of the above.
i. Both of the following.
i. Specifications of any fire safety equipment provided, including all of the following.
• Operational details.
• Operators’ manuals.
• Software.
• System zoning.
• Routine inspection, testing and maintenance schedules.
ii. Records of any acceptance or commissioning tests.
j. Any other details appropriate for the specific building.
The records should include details of all of the following.
d. All passive fire safety measures, including all of the following.
i. Compartmentation (i.e. location of fire-separating elements).
ii. Cavity barriers.
iii. Fire doorsets, including fire doorsets fitted with a self-closing device and other doors equipped with relevant hardware (e.g. electronic security locks).
iv. Duct dampers.
v. Fire shutters.
The records should include details of all of the following.
d. All passive fire safety measures, including all of the following.
iii. Fire doorsets, including fire doorsets fitted with a self-closing device and other doors equipped with relevant hardware (e.g. electronic security locks).
See para 2.5
Fire resisting construction minimum REI 30
Fd Fire doorset minimum E 20
See Diagram 2.1c. The dwellinghouse should have either of the following. Cavity barriers or a fire resisting ceiling (minimum EI 30) should be provided above a protected stairway enclosure (Diagram 2.3). b. Alternative escape route – a top storey separated from lower storeys by fire resisting construction (minimum REI 30) and with an alternative escape route leading to its own final exit.
a. Protected stairway – a stair separated by fire resisting construction (minimum REI 30) at all storeys, that complies with one of the following.
i. Extends to a final exit (Diagram 2.2a).
ii. Gives access to a minimum of two ground level final exits that are separated from each other by fire resisting construction (minimum REI 30) and fire doorsets (minimum E 20) (Diagram 2.2b).
Fire resisting window(minimum RE30)
No fire resistance required for door
1100mm zone above top landing
6m max. height without weather protection
1800mm zone of fire resisting construction at side of stairway
Fire doorset(minimum E30)
See para 2.17
No fire resistance required for door
1100mm zone above top landing
1100mm zone above top landing
6m maximum height of stair
Fire resisting window (minimum RE30)
1800mm zone of fire resisting construction at side of stair
Fire doorset (minimum E30)
Ground level or a roof or podium served by an independent stairway
6m maximum height of stair without weather protection
9m zone of fire resisting construction below stair
Ground level or a roof or podium served by an independent stairway
See para 3.68
Where access from any habitable room to the entrance hall or flat entrance is impossible without passing through another room, all of the following conditions should be met (Diagram 3.4).
a. Bedrooms should be separated from living accommodation by fire resisting construction (minimum REI 30) and fire doorsets (minimum E 20).
b. The alternative exit should be in the part of the flat that contains the bedrooms.
See para 3.18
NOTE: Bathrooms do not need to have fire doorsets provided that the bathroom is separated by fire resisting construction from the adjacent rooms.
Divide a common corridor connecting two or more storey exits with a fire doorset fitted with a self-closing device (minimum E 30 Sa). See Diagram 3.8. Associated screens should be fire resisting. Site doors so that smoke does not affect access to more than one stair.
A fire doorset (minimum E 30 Sa) fitted with a self-closing device (and fire resisting screen, where required) should separate the dead-end portion of a common corridor from the rest of the corridor (Diagrams 3.7a, 3.8b and 3.8c).
See para 3.19
NOTE: The bedrooms are not classified as inner rooms because escape is possible in two directions.
Fire doorset
Fire resisting construction (minimum REI 30) between living and bedroom accommodation
Alternative exit
Smoke vents should comply with one of the following.
a. They should be located on an external wall with minimum free area of 1.5m2.
b. They should discharge into a vertical smoke shaft, closed at the base, that meets all of the following criteria.
i. The shaft should conform to the following conditions.
• Have a minimum cross-sectional area of 1.5m2 (minimum dimension 0.85m in any direction).
• Open at roof level, minimum 0.5m above any surrounding structures within 2m of it horizontally.
• Extend a minimum of 2.5m above the ceiling of the highest storey served by the shaft.
ii. The free area of all the following vents should be a minimum of 1m2 in the following places.
• From the corridor or lobby into the shaft.
• At the opening at the head of the shaft.
• At all internal locations within the shaft (e.g. safety grilles).
iii. The smoke shaft should be constructed from a class A1 material. All vents should either be a smoke leakage (Sa) rated fire doorset (see Appendix C, Table C1, item 2.e for minimum fire resistance) or fitted with a smoke control damper achieving the same period of fire resistance and designed to operate as described below. The shaft should be vertical from base to head, with a maximum of 4m at a maximum inclined angle of 30 degrees.
iv. If smoke is detected in the common corridor or lobby, both of the following should occur.
• Simultaneous opening of vents on the storey where the fire is located, at the top of the smoke shaft and to the stair.
• Vents from the corridors or lobbies on all other storeys should remain closed, even if smoke is subsequently detected on storeys other than where the fire is located.
See para 3.21
NOTE: This only applies where at least one storey is more than 4.5m above ground level.
Fire doorset
Fire resisting stair enclosure(minimum REI 30)
Alternative exit
See paras 3.27 and 3.36
NOTES:
1. The arrangements shown also apply to the top storey.
2. See Diagram 3.9 for small single stair buildings.
3. All doors shown are fire doorsets.
4. Where travel distance is measured to a stair lobby, the lobby must not provide direct access to any storage room, flat or other space containing a potential fire hazard.
5. For further guidance on the fire rating of the fire doorsets from the corridor to the flat and/or stairway refer to Appendix C ,Table C1.
F Flat
Shaded areas indicate zones where ventilation should be provided in accordance with paragraphs 3.50 to 3.53(An external wall vent or smoke shaft located anywhere in the shaded area)
See paras 3.27 and 3.36
NOTES:
1. The arrangements shown also apply to the top storey.
2. See Diagram 3.9 for small single stair buildings.
3. All doors shown are fire doorsets.
4. Where travel distance is measured to a stair lobby, the lobby must not provide direct access to any storage room, flat or other space containing a potential fire hazard.
5. For further guidance on the fire rating of the fire doorsets from the corridor to the flat and/or stairway refer to Appendix C ,Table C1.
F Flat
Shaded areas indicate zones where ventilation should be provided in accordance with paragraphs 3.50 to 3.53(An external wall vent or smoke shaft located anywhere in the shaded area)
a. CORRIDOR ACCESS WITHOUT DEAD ENDS
b. CORRIDOR ACCESS WITH DEAD ENDS
The central door may be omitted if maximum travel distance is not more than 15m.
1. The arrangements shown also apply to the top storey.
2. For further guidance on the fire rating of the fire doorsets from the corridor to the flat and/or stairway refer to Appendix C ,Table C1.
Fire doorset provided in accordance with paragraphs 3.50 to 3.53(An external wall vent or smoke shaft located anywhere in the shaded area)
See paras 3.27 and 3.36
Fire resistance test criteria are set out in Appendix C. Standards of performance are summarised in Table C1.
If glazed elements in fire resisting enclosures and doors can only meet the required integrity performance, their use is limited. These limitations depend on whether the enclosure forms part of a protected shaft (see Section 7) and the provisions set out in Appendix B, Table B5. If both integrity and insulation performance can be met, there is no restriction in this document on the use or amount of glass.
a. SMALL SINGLE STAIR BUILDING
*If smoke control is provided in the lobby, the travel distance can be increased to 7.5m maximum(see Diagram 3.7, example b).
b. SMALL SINGLE STAIR BUILDING WITH NO MORE THAN TWO FLATS PER STOREY
The door between stair and lobby should be free from security fastenings.
If the flats have protected entrance halls, the lobby between the common stair and flat entrance is not essential.
NOTES:
1. The arrangements shown also apply to the top storey.
2. If the travel distance across the lobby in diagram (a) exceeds 4.5m, Diagram 3.7 applies.
3. Where,in Diagram (b), the lobby between the common stair and the dwelling is omitted in smal lsingle stair buildings, an automatic opening vent with a free area of at least 1m2 is required at the top of the stair,which is operated automatically on detection of smoke at any storey in the stair.
4. For further guidance on the fire rating of the fire doorsets from the corridor to the flat and/or stairway refer to Appendix C, Table C1.
Fire resisting construction
Openable vent at high level for fire service use (1.0m2 minimum free area); see paragraph 3.28eSee para 3.28
Diagram 3.9
Doors should be readily openable to avoid undue delay to people escaping. Doors on escape routes (both within and from the building) should comply with paragraphs 3.91 to 3.98. Guidance on door closing and ‘hold open’ devices for fire doorsets is set out in Appendix C.
NOTE: Paragraphs 3.91 to 3.98 do not apply to flat entrance doors.
Guidance on door closing and ‘hold open’ devices for fire doorsets is set out in Appendix C.
Openings should be limited to the following.
a. Fire doorsets with a minimum E 30 rating, fitted in accordance with Appendix C.
b. The passage of pipes that follow the provisions in Section 9.
c. The passage of cables or conduits containing one or more cables.
d. Openings fitted with a suitably mounted and appropriate fire damper.
e. Ducts that are either of the following.
i. Fire resisting (minimum E 30).
ii. Fitted with a suitably mounted and appropriate fire damper where they pass through the cavity barrier.
NOTE: For further guidance on openings in cavity barriers see Section 9.
Openings in a compartment wall common to two or more buildings should be limited to those for either of the following.
a. A fire doorset providing a means of escape, which has the same fire resistance as the wall and is fitted in accordance with the provisions in Appendix C.
b. The passage of a pipe that complies with the provisions in Section 9.
Fire resistance to protected shaft to be a maximum of REI 60
Fire resistance of construction to be a minimum of REI 30 (including fire doorsets that are a minimum of E 30 Sa)
Fire resistance of glazing to be a minimum of RE 30(including fire doorsets that are a minimum of E 30 Sa)
a. WITH CORRIDOR
b. WITH LOBBY
See para 7.25
Openings should be limited to those for any of the following.
a. Fire doorsets of the appropriate fire resistance, fitted in accordance with the provisions in Appendix C.
b. Pipes, ventilation ducts, service cables, chimneys, appliance ventilation ducts or ducts encasing one or more flue pipes, complying with the provisions in Section 9.
c. Refuse chutes of class A1 construction.
d. Atria designed in accordance with Annexes B and C of BS 9999.
e. Protected shafts that conform to the provisions in the following paragraphs.
The external wall of a protected shaft does not normally need to have fire resistance. Situations where there are provisions are given in paragraph 3.63 (external walls of protected stairways, which may also be protected shafts) and paragraphs 15.8 to 15.11 (firefighting shafts).
Openings in other parts of the enclosure to a protected shaft should be limited to the following.
a. If a wall common to two or more buildings forms part of the enclosure, only the following openings should be made in that wall.
i. A fire doorset providing a means of escape, which has the same fire resistance as the wall and is fitted in accordance with the provisions in Appendix C.
ii. The passage of a pipe that meets the provisions in Section 9.
b. Other parts of the enclosure (other than an external wall) should only have openings for any of the following.
i. Fire doorsets of the appropriate fire resistance, fitted in accordance with the provisions in Appendix C.
ii. The passage of pipes which meet the provisions in Section 9.
iii. Inlets to, outlets from and openings for a ventilation duct (if the shaft contains or serves as a ventilating duct), meeting the provisions in Section 9.
iv. The passage of lift cables into a lift machine room (if the shaft contains a lift). If the machine room is at the bottom of the shaft, the openings should be as small as practicable.
All fire doorsets should have the performance shown in Table C1, based on one of the following.
a. Fire resistance in terms of integrity, for a period of minutes, when tested to BS 476-22, e.g. FD 30.
A suffix (S) is added for doorsets where restricted smoke leakage at ambient temperatures is
needed.
b. As determined with reference to Commission Decision 2000/367/EC regarding the
classification of the resistance to fire performance of construction products, construction
works and parts thereof. All fire doorsets should be classified in accordance with BS EN 13501-2,
tested to the relevant European method from the following.
i. BS EN 1634-1.
ii. BS EN 1634-2.
iii. BS EN 1634-3.
c. As determined with reference to European Parliament and Council Directive 95/16/EC (which
applies to lifts that permanently serve buildings and constructions and specified safety
components) on the approximation of laws of Member States relating to lifts (‘Lifts Directive’)
implementing the
Unless shown to be satisfactory when tested as part of a fire doorset assembly, the essential components of any hinge on which a fire door is hung should be made entirely from materials that have a minimum melting point of 800°C.
Except for doorsets listed in paragraph C12, all fire doorsets should be marked with one of the
following fire safety signs, complying with BS 5499-5, as appropriate.
a. To be kept closed when not in use – mark ‘Fire door keep shut’.
b. To be kept locked when not in use – mark ‘Fire door keep locked shut’.
c. Held open by an automatic release mechanism or free swing device – mark ‘Automatic fire door
keep clear’.
All fire doorsets should be marked on both sides, except fire doorsets to cupboards and service
ducts, which should be marked on the outside.
The following fire doorsets are not required to comply with paragraph C11.
a. Doors to and within flats and dwellinghouses.
b. Bedroom doors in ‘residential (other)’ (purpose group 2(b)) premises.
c. Lift entrance/landing doors.
The performance of some doorsets set out in Table C1 is linked to the minimum periods of fire resistance for elements of structure given in Tables B3 and B4. Limitations on the use of uninsulated glazing in fire doorsets are given in Table B5.
Recommendations for the specification, design, construction, installation and maintenance of fire
doorsets constructed with non-metallic door leaves are given in BS 8214.
Guidance on timber fire resisting doorsets, in relation to the new European test standard, may be
found in Timber Fire Resisting Doorsets: Maintaining Performance Under the New European Test
Standard published by the Timber Research and Development Association (TRADA).
Guidance for metal doors is given in Code of Practice for Fire Resisting Metal Doorsets published by
the Door and Shutter Manufacturers’ Association (DSMA).
Any test evidence used to verify the fire resistance rating of a doorset or shutter should be
checked to ensure both of the following.
a. It adequately demonstrates compliance.
b. It is applicable to the complete installed assembly. Small differences in detail may significantly
affect the rating.
Until relevant harmonised product standards are published, for the purposes of meeting the
Building Regulations, products tested in accordance with BS EN 1634-1 (with or without pre-fire test
mechanical conditioning) that achieve the minimum performance in Table C1 will be deemed to
satisfy the provisions.
All fire doorsets, including to flat entrances and between a dwellinghouse and an integral garage,
should be fitted with a self-closing device, except for all of the following.
a. Fire doorsets to cupboards.
b. Fire doorsets to service ducts normally locked shut.
c. Fire doorsets within flats and dwellinghouses.
Two fire doorsets may be fitted in the same opening if each door is capable of closing the opening,
so the total fire resistance is the sum of their individual resistances. If the opening is provided as a
means of escape, both fire doorsets should be self-closing.
If one fire doorset is capable of being easily opened by hand and has a minimum of 30 minutes’ fire
resistance, the other fire doorset should comply with both of the following.
a. Be fitted with an automatic self-closing device.
b. Be held open by a fusible link.
Fire doorsets often do not provide any significant insulation. Unless providing both integrity
and insulation in accordance with Appendix B, Table B3, a maximum of 25% of the length of a
compartment wall should consist of door openings.
Where it is practicable to maintain a clear space on both sides of the doorway, the above
percentage may be greater.
fire protection
In the Secretary of State’s view, requirement B3 is met by achieving all of the following.
a. For defined periods, loadbearing elements of structure withstand the effects of fire without
loss of stability.
b. Compartmentation of buildings by fire resisting construction elements.
c. Automatic fire suppression is provided where it is necessary.
d. Protection of openings in fire-separating elements to maintain continuity of the fire separation.
e. Inhibition of the unseen spread of fire and smoke in cavities, in order to reduce the risk of
structural failure and spread of fire and smoke, where they pose a threat to the safety of people
in and around the building.
The extent to which any of these measures are necessary is dependent on the use of the building
and, in some cases, its size, and on the location of the elements of construction.
Access and facilities for the fire service
B5.(1)The building shall be designed and constructed so as to provide reasonable facilities to assist fire fighters in the protection of life.
(2)Reasonable provision shall be made within the site of the building to enable fire appliances to gain access to the building.
Flats
1. Within the enclosures of a protected entrance hall or protected landing, or within fire resisting separation shown in Section 3, Diagram 3.4.
2. Within either:
a. the enclosures of a protected stairway
b. fire resisting separation shown in Diagram 2.2.
3. Within fire resisting separation either:
a. shown in Diagram 2.4
b. described in paragraph 2.16b.
4. Existing window between an attached/integral garage and the dwellinghouse.
5. Adjacent to an external escape stair (see paragraph 2.17 and Diagram 2.7) or roof escape route (see paragraph 2.13).
6. Between residential/sleeping accommodation and a common escape route (corridor, lobby or stair).
7. Between a protected stairway(1)and either:
a. the accommodation
b. a corridor that is not a protected corridor other than in item 6 above.
8. Between either:
a. a protected stairway(1)and a protected lobby or protected corridor
b. accommodation and a protected lobby other than in item 6 above.
9. Between the accommodation and a protected corridor that forms a dead end,other than in item 6 above.
10.Between accommodation and any other corridor, or sub-dividing corridors,other than in item 6 above.
11. Beside an external escape route.
Table B5
see Table B3
Table B5
12. Beside an external escape stair (see paragraph 3.68 and Diagram 3.11) or roof escape route (see paragraph 3.30).
NOTES:
Items 1 and 8 apply also to single storey buildings.
Fire resisting glass should be marked with the name of the manufacturer and the name of the product.
Further guidance can be found in A Guide to Best Practice in the Specification and Use of Fire-resistant Glazed Systems published by the Glass and Glazing Federation.
1. If the protected stairway is also a protected shaft or a firefighting stair (see Section 15), there may be further
restrictions on the use of glazed elements.
2. Measured vertically from the landing floor level or the stair pitch line.
3. The 100mm limit is intended to reduce the risk of fire spreading from a floor covering.
While many of the provisions in this approved document for means of escape from flats are applicable to sheltered housing, the nature of the occupancy may necessitate some additional fire protection measures. The extent of such measures will depend on the form of the development. For example, a group of specially adapted bungalows or two storey flats, with few communal facilities, will not need to be treated differently from other single storey or two storey dwellinghouses or flats.
The Building Regulations do not impose any requirements on the management of a building, but do assume that it will be properly managed. This includes, for example, keeping protected escape routes virtually ‘fire sterile’.
Appropriate fire safety design considers the way in which a building will be managed. Any reliance on an unrealistic or unsustainable management regime cannot be considered to have met the requirements of the regulations.
Once the building is in use, the management regime should be maintained and a suitable risk assessment undertaken for any variation in that regime. Failure to take proper management responsibility may result in the prosecution of an employer, building owner or occupier under legislation such as the Regulatory Reform (Fire Safety) Order 2005.
The Building Regulations are intended to ensure a reasonable standard of life safety in a fire. The protection of property, including the building itself, often requires additional measures. Insurers usually set higher standards before accepting the insurance risk. Many insurers use the RISC Authority Design Guide for the Fire Protection of Buildings by the Fire Protection Association (FPA) as a basis for providing guidance to the building designer on what they require. Further information on the protection of property can be obtained from the FPA website: www.thefpa.co.uk.
All dwellings should have a fire detection and alarm system, minimum Grade D2 Category LD3
standard, in accordance with the relevant recommendations of BS 5839-6.
A higher standard of protection should be considered where occupants of a proposed dwelling
would be at special risk from fire. Further advice on this is also given in BS 5839-6.
Each flat in a block should have alarms as set out in paragraphs 1.1 to 1.4. With effective compartmentation, a communal fire alarm system is not normally needed. In some buildings, detectors in common parts of the building may need to operate smoke control or other fire protection systems but do not usually sound an audible warning.
Fire detection and alarm systems must be properly designed, installed and maintained. A design,
installation and commissioning certificate should be provided for fire detection and alarm systems.
Third party certification schemes for fire protection products and related services are an effective
means of providing assurances of quality, reliability and safety.
Buildings without firefighting shafts should be provided with fire mains where fire service vehicle access is not provided in accordance with paragraph 13.2(a). In these cases, the fire mains should be located within the protected stairway enclosure, with a maximum hose distance of 45m from the fire main outlet to the furthest point inside each flat, measured on a route suitable for laying a hose.
The outlets from fire mains should be located within the protected stairway enclosure (see Diagram 15.1).
Firefighting shafts and protected stairways should be positioned such that every part of each storey more than 18m above the fire and rescue service vehicle access level complies with the maximum distances given in paragraph 15.7. Distances should be measured from the fire main outlet on a route suitable for laying a hose.
NOTE: If the internal layout is not known, the distance should be measured at two-thirds of the direct distance.
In any building, the hose laying distance should meet all of the following conditions.
a. A maximum of 60m from the fire main outlet in a firefighting shaft (see Diagram 15.3).
b. Additionally, where sprinklers have not been provided in accordance with Appendix E, the hose laying distance should be a maximum of 45m from a fire main outlet in a protected stairway (although this does not imply that the protected stairway needs to be designed as a firefighting shaft (see Diagram 15.3)).
Basic information on the location of fire protection measures may be sufficient. An as-built plan of the building should be provided showing all of the following.
a. Escape routes – this should include exit capacity (i.e. the maximum allowable number of people for each storey and for the building).
b. Location of fire-separating elements (including cavity barriers in walk-in spaces).
c. Fire doorsets, fire doorsets fitted with a self-closing device and other doors equipped with relevant hardware.
d. Locations of fire and/or smoke detector heads, alarm call points, detection/alarm control boxes, alarm sounders, fire safety signage, emergency lighting, fire extinguishers, dry or wet fire mains and other firefighting equipment, and hydrants outside the building.
e. Any sprinkler systems, including isolating valves and control equipment.
f. Any smoke control systems, or ventilation systems with a smoke control function, including mode of operation and control systems.
g. Any high risk areas (e.g. heating machinery).
A detailed record should be provided of both of the following.
a. The fire safety strategy.
b. Procedures for operating and maintaining any fire protection measures. This should include an outline cause and effect matrix/strategy for the building.
Further guidance is available in clause 9 and Annex H of BS 9999.
A detailed record should be provided of both of the following.
b. Procedures for operating and maintaining any fire protection measures. This should include an outline cause and effect matrix/strategy for the building.
Further guidance is available in clause 9 and Annex H of BS 9999.
See Diagram 2.1c. The dwellinghouse should have either of the following. Cavity barriers or a fire resisting ceiling (minimum EI 30) should be provided above a protected stairway enclosure (Diagram 2.3). b. Alternative escape route – a top storey separated from lower storeys by fire resisting construction (minimum REI 30) and with an alternative escape route leading to its own final exit.
a. Protected stairway – a stair separated by fire resisting construction (minimum REI 30) at all storeys, that complies with one of the following.
i. Extends to a final exit (Diagram 2.2a).
ii. Gives access to a minimum of two ground level final exits that are separated from each other by fire resisting construction (minimum REI 30) and fire doorsets (minimum E 20) (Diagram 2.2b).
See Diagram 2.1d. In addition to meeting the provisions in paragraph 2.5, the dwellinghouse should comply with either of the following.
a. Provide an alternative escape route from each storey more than 7.5m above ground level. At the first storey above 7.5m, the protected stairway should be separated from the lower storeys by fire resisting construction (minimum REI 30) if the alternative escape route is accessed via either of the following.
i. The protected stairway to an upper storey.
ii. A landing within the protected stairway enclosure to an alternative escape route on the same storey. The protected stairway at or about 7.5m above ground level should be separated from the lower storeys or levels by fire resisting construction (see Diagram 2.4).
b. Provide a sprinkler system throughout, designed and installed in accordance with BS 9251.
Fire resisting window(minimum RE30)
No fire resistance required for door
1100mm zone above top landing
6m max. height without weather protection
1800mm zone of fire resisting construction at side of stairway
Fire doorset(minimum E30)
See para 2.17
All of the following precautions should be taken to avoid the spread of smoke and fire to the protected stairway.
a. Transfer grilles should not be fitted in any wall, door, floor or ceiling of the stair enclosure.
b. Any duct passing through the stair enclosure should be rigid steel. Joints between the ductwork and stair enclosure should be fire-stopped.
c. Ventilation ducts supplying or extracting air directly to or from a protected stairway should not serve other areas as well.
d. Any system of mechanical ventilation which recirculates air and which serves both the stair and other areas should be designed to shut down on the detection of smoke within the system.
e. For ducted warm air heating systems, a room thermostat should be sited in the living room. It should be mounted at a height between 1370mm and 1830mm above the floor. The maximum setting should be 27°C.
NOTE: Ventilation ducts passing through compartment walls should comply with the guidance in Section 9.
Configurations of stairs and external wall
Fire resisting construction
Fire resisting construction of adjacent building enclosure of protected stairway
Non-fire resisting construction
See para 3.63
No fire resistance required for door
1100mm zone above top landing
1100mm zone above top landing
6m maximum height of stair
Fire resisting window (minimum RE30)
1800mm zone of fire resisting construction at side of stair
Fire doorset (minimum E30)
Ground level or a roof or podium served by an independent stairway
6m maximum height of stair without weather protection
9m zone of fire resisting construction below stair
Ground level or a roof or podium served by an independent stairway
See para 3.68
Provisions are recommended to support a stay put evacuation strategy for blocks of flats. It is based on the principle that a fire is contained in the flat of origin and common escape routes are maintained relatively free from smoke and heat. It allows occupants, some of whom may require assistance to escape in the event of a fire, in other flats that are not affected to remain.
Sufficient protection to common means of escape is necessary to allow occupants to escape should they choose to do so or are instructed/aided to by the fire service. A higher standard of protection is therefore needed to ensure common escape routes remain available for a longer period than is provided in other buildings.
A protected circuit to operate equipment during a fire should achieve all of the following.
a. Cables should achieve PH 30 classification when tested in accordance with BS EN 50200 (incorporating Annex E) or an equivalent standard.
b. It should only pass through parts of the building in which the fire risk is negligible.
c. It should be separate from any circuit provided for another purpose.
Despite the provisions described, it is probable that some smoke will get into the common corridor or lobby from a fire in a flat.
There should therefore be some means of ventilating the common corridors/lobbies to control smoke and so protect the common stairs. This means of ventilation offers additional protection to that provided by the fire doors to the stair, as well as some protection to the corridors/lobbies.
Ventilation can be natural (paragraphs 3.50 to 3.53) or mechanical (paragraph 3.54).
With some configurations of external wall, a fire in one part of a building could subject the external wall of a protected stairway to heat (for example, where the two are adjacent at an internal angle in the façade, as shown in Diagram 3.10).
Where a stair serves an enclosed car park or place of special fire hazard, the lobby or corridor should have a minimum 0.4m2 of permanent ventilation or be protected from the ingress of smoke by a mechanical smoke control system.
NOTE: For refuse chutes and storage see paragraphs 3.55 to 3.58.
Every protected stairway should lead to a final exit, either directly or via a protected exit passageway. Any protected exit corridor or stair should have the same standard of fire resistance and lobby protection as the stair it serves.
a. ANY BUILDING OR COMPARTMENT
Roof covering over this distance to be designated BROOF(t4) rated on deck of material of class A2-s3, d2 or better. Roof covering and deck could be composite structure, e.g. profiled steel cladding.
Fire-stopping to be carried up to underside of roof covering, boarding or slab.
Roof covering to be designated BROOF(t4) rated for at least 1500mm either side of wall.
b. RESIDENTIAL (DWELLINGS) AND RESIDENTIAL (OTHER) A MAXIMUM OF 15M HIGH
Boarding (used as a substrate) or timber tiling battens may be carried over the wall provided that they are fully bedded in mortar (or other no less suitable material) where over the wall.
Thermoplastic insulation materials should not be carried over the wall.
Double-skinned insulated roof sheeting with a thermoplastic core should incorporate a band of material of class A2-s3, d2 at least 300mm wide centred over the wall.
Sarking felt may also be carried over the wall.
If roof support members pass through the wall, fire protection to these members for a distance of 1500mm on either side of the wall may be needed to delay distortion at the junction (see paragraph 5.9).
Double-skinned insulated roof sheeting should incorporate a band of material rated class A2-s3, d2 or better, a minimum of 300mm in width, centred over the wall.
If roof support members pass through the wall, fire protection to these members for a distance of 1500mm on either side of the wall may be needed to delay distortion at the junction (see paragraph 5.9).
Fire-stopping to be carried up to underside of roof covering, e.g. roof tiles.
Section X–X
Roof covering to be designated BROOF(t4) rated for at least this distance.
Roofing battens and sarking felt may be carried over the wall.
Fire-stopping to be carried up to underside of roof covering above and below sarking felt.
NOTES:
1. Fire-stopping should be carried over the full thickness of the wall.
2. Fire-stopping should be extended into any eaves.
3. The compartment wall does not necessarily need to be constructed of masonry.
c. ANY BUILDING OR COMPARTMENT
The wall should be extended up through the roof for a height of at least 375mm above the top surface of the adjoining roof covering.
Where there is a height difference of at least 375mm between two roofs or where the roof coverings on either side of the wall are BROOF(t4) rated, the height of the upstand/parapet wall above the highest roof may be reduced to 200mm.
See paras 5.12 to 5.15
If a loadbearing wall is any of the following, guidance in other sections may also apply.
a. A compartment wall (including a wall common to two buildings): Section 7.
b. Enclosing a place of special fire hazard: Section 7.
c. Protecting a means of escape: Sections 2 and 3.
d. An external wall: Sections 10 and 11.
e. Enclosing a firefighting shaft: Section 15.
Fire resistance to protected shaft to be a maximum of REI 60
Fire resistance of construction to be a minimum of REI 30 (including fire doorsets that are a minimum of E 30 Sa)
Fire resistance of glazing to be a minimum of RE 30(including fire doorsets that are a minimum of E 30 Sa)
a. WITH CORRIDOR
b. WITH LOBBY
See para 7.25
Stairs and service shafts connecting compartments should be protected to restrict the spread of fire between the compartments. These are called protected shafts. Walls or floors surrounding a protected shaft are considered to be compartment walls or compartment floors.
An uninsulated glazed screen may be incorporated in the enclosure to a protected shaft between a stair and a lobby or corridor entered from the stair. The enclosure must conform to Diagram 7.2 and meet all of the following conditions.
a. The standard of fire resistance required for the protected stairway is not more than REI 60.
b. The glazed screen complies with the following.
i. It achieves a minimum rating of E 30.
ii. It complies with the guidance on limits on areas of uninsulated glazing in Appendix B, Table B5.
c. The lobby or corridor is enclosed with fire resisting construction achieving a minimum rating of REI 30.
A protected shaft containing a protected stairway and/or a lift should not also contain either of the following.
a. A pipe that conveys oil, other than in the mechanism of a hydraulic lift.
b. A ventilating duct. Two exceptions are as follows.
i. A duct provided for pressurising the protected stairway to keep it smoke free.
ii. A duct provided only to ventilate the protected stairway.
A pipe that is completely separated from a protected shaft by fire resisting construction is not considered to be contained within that shaft.
The external wall of a protected shaft does not normally need to have fire resistance. Situations where there are provisions are given in paragraph 3.63 (external walls of protected stairways, which may also be protected shafts) and paragraphs 15.8 to 15.11 (firefighting shafts).
Openings in other parts of the enclosure to a protected shaft should be limited to the following.
a. If a wall common to two or more buildings forms part of the enclosure, only the following openings should be made in that wall.
i. A fire doorset providing a means of escape, which has the same fire resistance as the wall and is fitted in accordance with the provisions in Appendix C.
ii. The passage of a pipe that meets the provisions in Section 9.
b. Other parts of the enclosure (other than an external wall) should only have openings for any of the following.
i. Fire doorsets of the appropriate fire resistance, fitted in accordance with the provisions in Appendix C.
ii. The passage of pipes which meet the provisions in Section 9.
iii. Inlets to, outlets from and openings for a ventilation duct (if the shaft contains or serves as a ventilating duct), meeting the provisions in Section 9.
iv. The passage of lift cables into a lift machine room (if the shaft contains a lift). If the machine room is at the bottom of the shaft, the openings should be as small as practicable.
If the fire resisting construction of a protected escape route is either of the following.
a. Not carried to full storey height.
b. At the top storey, not carried to the underside of the roof covering.
Then the cavity above or below the fire resisting construction should be either of the following.
i. Fitted with cavity barriers on the line of the enclosure.
ii. For cavities above the fire resisting construction, enclosed on the lower side by a fire resisting ceiling (minimum EI 30) that extends throughout the building, compartment or separated part (see Diagram 8.3).
If air handling ducts pass through fire-separating elements, the fire performance of the elements should be maintained using one or more of the following four methods. In most ductwork systems, a combination of the four methods is best.
a. Method 1 – thermally activated fire dampers.
b. Method 2 – fire resisting enclosures.
c. Method 3 – protection using fire resisting ductwork.
d. Method 4 – automatically activated fire and smoke dampers triggered by smoke detectors.
An ES classified fire and smoke damper which is activated by a suitable fire detection system (method 4) may also be used for protected escape routes.
Guidance on the design, installation and maintenance of measures to contain fires or slow their spread is given in Ensuring Best Practice for Passive Fire Protection in Buildings produced by the Association for Specialist Fire Protection (ASFP).
NOTE:
Ventilation ducts which serve other parts of the building should not supply or extract air directly to or from a protected escape route.
Ductwork enclosed in fire resisting construction classified EI X in accordance with BSEN13501-2 (fire exposure from the duct side), or fire resisting ductwork classified EIS X in accordance with BS EN 13501-3, where X is the fire resistance rating (in minutes) of the walls of the protected escape route
See para 9.16
ES leakage rated fire and smoke damper conforming to BS EN 13501-3/BS EN 1366-2
Smoke detection system in accordance with BS 5839-1 to activate ES damper
Ductwork passing through protected escape routes–method 4
NOTE:
Ventilation ducts which serve other parts of the building should not supply or extract air directly to or from a protected escape route.
See para 9.16
A fire and smoke damper should be provided where ductwork enters or leaves each section of the protected escape route it serves. It should be operated by a smoke detector or suitable fire detection system. Fire and smoke dampers should close when smoke is detected. Alternatively, the methods set out in paragraphs 9.16 and 9.17 and Diagrams 9.3 and 9.4 may be followed.
Where it is proposed to assess the classification of a product or system in lieu of carrying out a specific test (as in paragraph B1c), this should be done in accordance with the relevant standard for extended application for the test in question and should include details of the test evidence that has been used to support the assessment.
For performance classifications where there is no specific standard for extended
application, assessment reports should be produced in accordance with the principles of BS EN 15725 and should include details of the test evidence that has been used to support the assessment. Further information on best practice is provided in the Passive Fire Protection Forum’s Guide to Undertaking Technical Assessments of the Fire Performance of Construction Products Based on Fire Test Evidence.
NOTE: Regulation 7(2) limits components used in or on the external walls of certain buildings to materials achieving class A2-s1, d0 or class A1 (see Section 12).
Assessments cannot be used to demonstrate compliance with this requirement.
fire resistance
In the Secretary of State’s view, requirement B3 is met by achieving all of the following.
a. For defined periods, loadbearing elements of structure withstand the effects of fire without
loss of stability.
b. Compartmentation of buildings by fire resisting construction elements.
c. Automatic fire suppression is provided where it is necessary.
d. Protection of openings in fire-separating elements to maintain continuity of the fire separation.
e. Inhibition of the unseen spread of fire and smoke in cavities, in order to reduce the risk of
structural failure and spread of fire and smoke, where they pose a threat to the safety of people
in and around the building.
The extent to which any of these measures are necessary is dependent on the use of the building
and, in some cases, its size, and on the location of the elements of construction.
see Table B4
See Table C1
See Appendix C
NOTES:
1. BS EN 13501-2 Classification using data from fire resistance tests, excluding ventilation services.BS EN 13501-3
Classification using data from fire resistance tests on products and elements used in building service installations: fire resisting ducts and fire dampers. BS EN 13501-4 Classification using data from fire resistance tests on components of smoke control systems.
In the European classification:
‘R’ is the resistance to fire in terms of loadbearing capacity.
‘E’ is the resistance to fire in terms of integrity.
‘I’ is the resistance to fire in terms of insulation.
The national classifications do not automatically equate with the alternative classifications in the European column, therefore products cannot typically assume a European class unless they have been tested accordingly.
2. BS 476-20 for general principles,BS 476-21 for loadbearing elements,BS 476-22 for non-loadbearing elements,BS 476-23 for fire-protecting suspended ceilings and BS 476-24 for ventilation ducts.
3. Applies to loadbearing elements only (see paragraph B19).
4. Guidance on increasing the fire resistance of existing timber floors is given in BRE Digest 208.
5. Only if a suspended ceiling meets the appropriate provisions should it be relied on to add to the fire resistance of the floor.
6. Such walls may contain areas that do not need to be fire resisting (unprotected areas). See Section 11.
7. Unless needed as part of a wall in item 5a or 5b.
8. Except for any limitations on uninsulated glazed elements given in Table B5.
This section provides guidance on resisting fire spread over external walls; however, it does not deal with fire resistance of external walls. An external wall may need fire resistance to meet the provisions of Section 3 (Means of escape – flats), Section 6 (Loadbearing elements of structure – flats), Section 11 (Resisting fire spread from one building to another) or Section 15 (Access to buildings for firefighting personnel – flats).
The following assumptions enable a reasonable standard of resistance to the spread of fire to be specified.
a. The size of a fire depends on the compartmentation within the building. A fire may involve a complete compartment, but will not spread to other compartments.
b. The intensity of a fire is related to the building use, but can be moderated by a sprinkler system.
c. Fires in ‘residential’ and ‘assembly and recreation’ buildings (purpose groups 1, 2 and 5) represent a greater risk to life.
d. A building on the far side of the relevant boundary meets both of the following conditions.
i. Has a similar elevation to the one in question.
ii. Is the same distance as the one in question from the common boundary.
e. The radiated heat passing through any part of the fire resisting external wall may be discounted.
Area of fire resisting wall with materials more than 1mm thick and with a reaction to fire performance worse than class B-s3, d2 = a x b
Area of wall counted as unprotected area = 0.5a x b
Area of fire resisting wall with materials having a reaction to fire performance better than class B-s3, d2
See para 11.7
Parts of an external wall with less fire resistance than the appropriate amount given in Appendix B, Table B4, are called unprotected areas.
Where a fire resisting external wall has an external surface material that is worse than class B-s3, d2 and is more than 1mm thick, that part of the wall should be classified as an unprotected area equating to half its area (Diagram 11.4).
Unprotected areas should not exceed the result given by one of the methods in paragraph 11.16, and the rest of the wall (if any) should be fire resisting but only from the inside of the building.
Minimum fire resistance REI60 from both sides with E30 Sa fire doors
Minimum fire resistance REI 120 from accommodation side and REI60 from inside the shaft with E60 Sa fire doors
NOTES:
1.Outlets from a fire main should be located in the firefighting lobby or, in the case of a shaft serving flats, in the firefighting stairway (see Diagram b).
2.Smoke control should be provided in accordance with BS9999 or, where the firefighting shaft only serves flats, the provisions for smoke control given in paragraph 3.49 may be followed instead.
3.A firefighting lift is required if the building has a floor more than 18m above, or more than 10m below, fire service vehicle access level.
4.This diagram is only to illustrate the basic components and is not meant to represent the only acceptable layout. The firefighting shaft should be constructed generally in accordance with section 6 of BS 9999.
5.For the minimum fire resistance of lift doors see Table C1.
See paras 15.2,15.8 and 15.9
Outlet ducts or shafts, including any bulkheads over them (see Diagram 16.1), should be enclosed in construction of class A1 rating and fire resistance at least equal to that of the element through which they pass.
Any external escape stair should meet all of the following conditions (Diagram 2.7).
a. Doors to the stair should be fire resisting (minimum E 30), except for a single exit door from the building to the top landing of a downward-leading external stair.
b. Fire resisting construction (minimum RE 30) is required for the building envelope within the following zones, measured from the flights and landings of the external stair.
i. 1800mm horizontally.
ii. 9m vertically below.
iii. 1100mm above the top landing of the stair (except where the stair leads from basement to ground level).
c. Fire resisting construction (minimum RE 30) should be provided for any part of the building (including doors) within 1800mm of the escape route from the foot of the stair to a place of safety. This does not apply if there are alternative escape routes from the foot of the external escape stair.
d. Stairs more than 6m in height should be protected from adverse weather. Protection should prevent the build-up of snow or ice but does not require full enclosure.
e. Glazing in areas of fire resisting construction should be fixed shut and fire resisting (in terms of integrity, but not insulation) (minimum E 30).
See para 2.5
Fire resisting construction minimum REI 30
Fd Fire doorset minimum E 20
An alternative approach to that described in paragraph 2.21 would be to comply with all of the following.
a. Provide sprinkler protection to the open-plan areas.
b. Provide a fire resisting partition (minimum REI 30) and door (minimum E 20) to separate the ground storey from the upper storeys. The door should allow occupants of the loft room access to a first storey escape window.
c. Separate cooking facilities from the open-plan area with fire resisting construction (minimum REI 30).
See Diagram 2.1d. In addition to meeting the provisions in paragraph 2.5, the dwellinghouse should comply with either of the following.
a. Provide an alternative escape route from each storey more than 7.5m above ground level. At the first storey above 7.5m, the protected stairway should be separated from the lower storeys by fire resisting construction (minimum REI 30) if the alternative escape route is accessed via either of the following.
i. The protected stairway to an upper storey.
ii. A landing within the protected stairway enclosure to an alternative escape route on the same storey. The protected stairway at or about 7.5m above ground level should be separated from the lower storeys or levels by fire resisting construction (see Diagram 2.4).
b. Provide a sprinkler system throughout, designed and installed in accordance with BS 9251.
Fire resisting window(minimum RE30)
No fire resistance required for door
1100mm zone above top landing
6m max. height without weather protection
1800mm zone of fire resisting construction at side of stairway
Fire doorset(minimum E30)
See para 2.17
Configurations of stairs and external wall
Fire resisting construction
Fire resisting construction of adjacent building enclosure of protected stairway
Non-fire resisting construction
See para 3.63
No fire resistance required for door
1100mm zone above top landing
1100mm zone above top landing
6m maximum height of stair
Fire resisting window (minimum RE30)
1800mm zone of fire resisting construction at side of stair
Fire doorset (minimum E30)
Ground level or a roof or podium served by an independent stairway
6m maximum height of stair without weather protection
9m zone of fire resisting construction below stair
Ground level or a roof or podium served by an independent stairway
See para 3.68
See para 3.18
NOTE: Bathrooms do not need to have fire doorsets provided that the bathroom is separated by fire resisting construction from the adjacent rooms.
A fire doorset (minimum E 30 Sa) fitted with a self-closing device (and fire resisting screen, where required) should separate the dead-end portion of a common corridor from the rest of the corridor (Diagrams 3.7a, 3.8b and 3.8c).
Fire resistance test criteria are set out in Appendix C. Standards of performance are summarised in Table C1.
Guidance on door closing and ‘hold open’ devices for fire doorsets is set out in Appendix C.
Lift wells should comply with one of the following conditions.
a. Be sited within the enclosures of a protected stairway.
b. Be enclosed with fire resisting construction (minimum REI 30) when in a position that might prejudice the means of escape.
Fire doors between the garage and dwellinghouse to have a minimum fire resistance of E30 Sa and be fitted with a self-closing device
Wall and any floor between the garage and dwellinghouse to have a minimum fire resistance of REI 30 from the garage side
The door opening threshold should be a minimum of 100mm above garage floor or
Floor to fall away from door to the outside
See paras 5.6 and 5.7
Elements of structure such as structural frames, beams, columns, loadbearing walls (internal and external), floor structures and gallery structures should have, as a minimum, the fire resistance given in Appendix B, Table B3.
If one element of structure supports or stabilises another, as a minimum the supporting element should have the same fire resistance as the other element.
If a garage is attached to or forms an integral part of a dwellinghouse, the garage should be separated from the rest of the dwellinghouse by fire resisting construction (minimum REI 30) (Diagram 5.1).
Elements of structure such as structural frames, beams, columns, loadbearing walls (internal and external), floor structures and gallery structures should have, as a minimum, the fire resistance given in Appendix B, Table B3.
NOTE: If one element of structure supports or stabilises another, as a minimum the supporting element should have the same fire resistance as the other element.
In a converted building with a maximum of three storeys, a minimum REI 30 fire resistance could be accepted for elements of structure if the means of escape conform to the provisions of Section 3.
In a converted building with four or more storeys, the full standard of fire resistance given in Appendix B is necessary.
An uninsulated glazed screen may be incorporated in the enclosure to a protected shaft between a stair and a lobby or corridor entered from the stair. The enclosure must conform to Diagram 7.2 and meet all of the following conditions.
a. The standard of fire resistance required for the protected stairway is not more than REI 60.
b. The glazed screen complies with the following.
i. It achieves a minimum rating of E 30.
ii. It complies with the guidance on limits on areas of uninsulated glazing in Appendix B, Table B5.
c. The lobby or corridor is enclosed with fire resisting construction achieving a minimum rating of REI 30.
Compartment walls forming a separated part of a building should run the full height of the building in a continuous vertical plane.
Separated parts can be assessed independently to determine the appropriate standard of fire resistance in each. The two separated parts can have different standards of fire resistance.
If the fire resisting construction of a protected escape route is either of the following.
a. Not carried to full storey height.
b. At the top storey, not carried to the underside of the roof covering.
Then the cavity above or below the fire resisting construction should be either of the following.
i. Fitted with cavity barriers on the line of the enclosure.
ii. For cavities above the fire resisting construction, enclosed on the lower side by a fire resisting ceiling (minimum EI 30) that extends throughout the building, compartment or separated part (see Diagram 8.3).
Further information on fire resisting ductwork is given in the ASFP Blue Book.
Provide a proprietary, tested sealing system that will maintain the fire resistance of the wall, floor or cavity barrier.
a. Flue passing through compartment wall or floor
b. Flue built into compartment wall
Flue walls should have a fire resistance of at least one half of that required for the compartment wall or floor and be of class A1construction.
In each case flue walls should have a fire resistance of at least one half of that required for the compartment wall and be of class A1 construction.
See para 9.23
Performance of the resistance of roofs to external fire exposure is measured in terms of penetration through the roof construction and the spread of flame over its surface.
Common to all of the provisions of Part B of the Building Regulations is the property of fire
resistance. Fire resistance is a measure of one or more of the following.
a. Resistance to collapse (loadbearing capacity), which applies to loadbearing elements only,
denoted R in the European classification of the resistance to fire performance.
b. Resistance to fire penetration (integrity), denoted E in the European classification of the
resistance to fire performance.
c. Resistance to the transfer of excessive heat (insulation), denoted I in the European
classification of the resistance to fire performance.
The fire resistance necessary for different circumstances is set out in the following tables.
a. Table B3 gives the specific requirements for each element of structure.
b. Table B4 sets out the minimum periods of fire resistance for elements of structure.
c. Table B5 sets out limitations on the use of uninsulated fire resisting glazed elements.
The following guidance should be used when applying the fire resistance standards in Table B4.
a. If one element of structure supports or carries or gives stability to another, the fire resistance
of the supporting element should be no less than the minimum period of fire resistance for the
other element (whether that other element is loadbearing or not). In some circumstances, it
may be reasonable to vary this principle, for example:
i. if the supporting structure is in the open air and is not likely to be affected by the fire in
the building
ii. if the supporting structure is in a different compartment, with a fire-separating element
(that has the higher standard of fire resistance) between the supporting and the separated
structure
iii. if a plant room on the roof needs greater fire resistance than the elements of structure
that support it.
b. If an element of structure forms part of more than one building or compartment, that element
should be constructed to the standard of the higher of the relevant provisions.
c. If, due to the slope of the ground, one side of a basement is open at ground level (allowing
smoke to vent and providing access for firefighting) for elements of structure in that storey
it may be appropriate to adopt the standard of fire resistance that applies to above-ground
structures.
d. Although most elements of structure in a single storey building may not need fire resistance,
fire resistance is needed if one of the following applies to the element.
i. It is part of, or supports, an external wall, and there is provision in the guidance on
requirement B4 to limit the extent of openings and other unprotected areas in the wall.
ii. It is part of, or supports, a compartment wall, including a wall that is common to two or
more buildings.
iii. It supports a gallery.
All fire doorsets should have the performance shown in Table C1, based on one of the following.
a. Fire resistance in terms of integrity, for a period of minutes, when tested to BS 476-22, e.g. FD 30.
A suffix (S) is added for doorsets where restricted smoke leakage at ambient temperatures is
needed.
b. As determined with reference to Commission Decision 2000/367/EC regarding the
classification of the resistance to fire performance of construction products, construction
works and parts thereof. All fire doorsets should be classified in accordance with BS EN 13501-2,
tested to the relevant European method from the following.
i. BS EN 1634-1.
ii. BS EN 1634-2.
iii. BS EN 1634-3.
c. As determined with reference to European Parliament and Council Directive 95/16/EC (which
applies to lifts that permanently serve buildings and constructions and specified safety
components) on the approximation of laws of Member States relating to lifts (‘Lifts Directive’)
implementing the
Recommendations for the specification, design, construction, installation and maintenance of fire
doorsets constructed with non-metallic door leaves are given in BS 8214.
Guidance on timber fire resisting doorsets, in relation to the new European test standard, may be
found in Timber Fire Resisting Doorsets: Maintaining Performance Under the New European Test
Standard published by the Timber Research and Development Association (TRADA).
Guidance for metal doors is given in Code of Practice for Fire Resisting Metal Doorsets published by
the Door and Shutter Manufacturers’ Association (DSMA).
Two fire doorsets may be fitted in the same opening if each door is capable of closing the opening,
so the total fire resistance is the sum of their individual resistances. If the opening is provided as a
means of escape, both fire doorsets should be self-closing.
If one fire doorset is capable of being easily opened by hand and has a minimum of 30 minutes’ fire
resistance, the other fire doorset should comply with both of the following.
a. Be fitted with an automatic self-closing device.
b. Be held open by a fusible link.
fire resisting (Fire resistance)
see Table B4
See Table C1
See Appendix C
NOTES:
1. BS EN 13501-2 Classification using data from fire resistance tests, excluding ventilation services.BS EN 13501-3
Classification using data from fire resistance tests on products and elements used in building service installations: fire resisting ducts and fire dampers. BS EN 13501-4 Classification using data from fire resistance tests on components of smoke control systems.
In the European classification:
‘R’ is the resistance to fire in terms of loadbearing capacity.
‘E’ is the resistance to fire in terms of integrity.
‘I’ is the resistance to fire in terms of insulation.
The national classifications do not automatically equate with the alternative classifications in the European column, therefore products cannot typically assume a European class unless they have been tested accordingly.
2. BS 476-20 for general principles,BS 476-21 for loadbearing elements,BS 476-22 for non-loadbearing elements,BS 476-23 for fire-protecting suspended ceilings and BS 476-24 for ventilation ducts.
3. Applies to loadbearing elements only (see paragraph B19).
4. Guidance on increasing the fire resistance of existing timber floors is given in BRE Digest 208.
5. Only if a suspended ceiling meets the appropriate provisions should it be relied on to add to the fire resistance of the floor.
6. Such walls may contain areas that do not need to be fire resisting (unprotected areas). See Section 11.
7. Unless needed as part of a wall in item 5a or 5b.
8. Except for any limitations on uninsulated glazed elements given in Table B5.
This section provides guidance on resisting fire spread over external walls; however, it does not deal with fire resistance of external walls. An external wall may need fire resistance to meet the provisions of Section 3 (Means of escape – flats), Section 6 (Loadbearing elements of structure – flats), Section 11 (Resisting fire spread from one building to another) or Section 15 (Access to buildings for firefighting personnel – flats).
The following assumptions enable a reasonable standard of resistance to the spread of fire to be specified.
a. The size of a fire depends on the compartmentation within the building. A fire may involve a complete compartment, but will not spread to other compartments.
b. The intensity of a fire is related to the building use, but can be moderated by a sprinkler system.
c. Fires in ‘residential’ and ‘assembly and recreation’ buildings (purpose groups 1, 2 and 5) represent a greater risk to life.
d. A building on the far side of the relevant boundary meets both of the following conditions.
i. Has a similar elevation to the one in question.
ii. Is the same distance as the one in question from the common boundary.
e. The radiated heat passing through any part of the fire resisting external wall may be discounted.
Area of fire resisting wall with materials more than 1mm thick and with a reaction to fire performance worse than class B-s3, d2 = a x b
Area of wall counted as unprotected area = 0.5a x b
Area of fire resisting wall with materials having a reaction to fire performance better than class B-s3, d2
See para 11.7
Parts of an external wall with less fire resistance than the appropriate amount given in Appendix B, Table B4, are called unprotected areas.
Where a fire resisting external wall has an external surface material that is worse than class B-s3, d2 and is more than 1mm thick, that part of the wall should be classified as an unprotected area equating to half its area (Diagram 11.4).
Unprotected areas should not exceed the result given by one of the methods in paragraph 11.16, and the rest of the wall (if any) should be fire resisting but only from the inside of the building.
Minimum fire resistance REI60 from both sides with E30 Sa fire doors
Minimum fire resistance REI 120 from accommodation side and REI60 from inside the shaft with E60 Sa fire doors
NOTES:
1.Outlets from a fire main should be located in the firefighting lobby or, in the case of a shaft serving flats, in the firefighting stairway (see Diagram b).
2.Smoke control should be provided in accordance with BS9999 or, where the firefighting shaft only serves flats, the provisions for smoke control given in paragraph 3.49 may be followed instead.
3.A firefighting lift is required if the building has a floor more than 18m above, or more than 10m below, fire service vehicle access level.
4.This diagram is only to illustrate the basic components and is not meant to represent the only acceptable layout. The firefighting shaft should be constructed generally in accordance with section 6 of BS 9999.
5.For the minimum fire resistance of lift doors see Table C1.
See paras 15.2,15.8 and 15.9
Outlet ducts or shafts, including any bulkheads over them (see Diagram 16.1), should be enclosed in construction of class A1 rating and fire resistance at least equal to that of the element through which they pass.
Any external escape stair should meet all of the following conditions (Diagram 2.7).
a. Doors to the stair should be fire resisting (minimum E 30), except for a single exit door from the building to the top landing of a downward-leading external stair.
b. Fire resisting construction (minimum RE 30) is required for the building envelope within the following zones, measured from the flights and landings of the external stair.
i. 1800mm horizontally.
ii. 9m vertically below.
iii. 1100mm above the top landing of the stair (except where the stair leads from basement to ground level).
c. Fire resisting construction (minimum RE 30) should be provided for any part of the building (including doors) within 1800mm of the escape route from the foot of the stair to a place of safety. This does not apply if there are alternative escape routes from the foot of the external escape stair.
d. Stairs more than 6m in height should be protected from adverse weather. Protection should prevent the build-up of snow or ice but does not require full enclosure.
e. Glazing in areas of fire resisting construction should be fixed shut and fire resisting (in terms of integrity, but not insulation) (minimum E 30).
See para 2.5
Fire resisting construction minimum REI 30
Fd Fire doorset minimum E 20
An alternative approach to that described in paragraph 2.21 would be to comply with all of the following.
a. Provide sprinkler protection to the open-plan areas.
b. Provide a fire resisting partition (minimum REI 30) and door (minimum E 20) to separate the ground storey from the upper storeys. The door should allow occupants of the loft room access to a first storey escape window.
c. Separate cooking facilities from the open-plan area with fire resisting construction (minimum REI 30).
See Diagram 2.1d. In addition to meeting the provisions in paragraph 2.5, the dwellinghouse should comply with either of the following.
a. Provide an alternative escape route from each storey more than 7.5m above ground level. At the first storey above 7.5m, the protected stairway should be separated from the lower storeys by fire resisting construction (minimum REI 30) if the alternative escape route is accessed via either of the following.
i. The protected stairway to an upper storey.
ii. A landing within the protected stairway enclosure to an alternative escape route on the same storey. The protected stairway at or about 7.5m above ground level should be separated from the lower storeys or levels by fire resisting construction (see Diagram 2.4).
b. Provide a sprinkler system throughout, designed and installed in accordance with BS 9251.
Fire resisting window(minimum RE30)
No fire resistance required for door
1100mm zone above top landing
6m max. height without weather protection
1800mm zone of fire resisting construction at side of stairway
Fire doorset(minimum E30)
See para 2.17
Configurations of stairs and external wall
Fire resisting construction
Fire resisting construction of adjacent building enclosure of protected stairway
Non-fire resisting construction
See para 3.63
No fire resistance required for door
1100mm zone above top landing
1100mm zone above top landing
6m maximum height of stair
Fire resisting window (minimum RE30)
1800mm zone of fire resisting construction at side of stair
Fire doorset (minimum E30)
Ground level or a roof or podium served by an independent stairway
6m maximum height of stair without weather protection
9m zone of fire resisting construction below stair
Ground level or a roof or podium served by an independent stairway
See para 3.68
See para 3.18
NOTE: Bathrooms do not need to have fire doorsets provided that the bathroom is separated by fire resisting construction from the adjacent rooms.
A fire doorset (minimum E 30 Sa) fitted with a self-closing device (and fire resisting screen, where required) should separate the dead-end portion of a common corridor from the rest of the corridor (Diagrams 3.7a, 3.8b and 3.8c).
Any external escape stair should meet all of the following conditions (Diagram 3.11).
a. Doors to the stair should be fire resisting (minimum E 30) and be fitted with a self-closing device, except for a single exit door from the building to the top landing of a downward-leading external stair, provided it is the only door onto the landing.
b. Fire resisting construction (minimum RE 30) is required for the building envelope within the following zones, measured from the flights and landings of the external stair.
i. 1800mm above and horizontally.
ii. 9m vertically below.
iii. 1100mm above the top landing of the stair (except where the stair leads from basement to ground level).
c. Fire resisting construction (minimum RE 30) should be provided for any part of the building (including doors) within 1800mm of the escape route from the foot of the stair to a place of safety. This does not apply if there are alternative escape routes from the foot of the external escape stair.
d. Glazing in areas of fire resisting construction should be fixed shut and fire resisting (in terms of integrity but not insulation) (minimum E 30).
e. Stairs more than 6m in height above ground level (e.g. where they are provided above a podium) should be protected from adverse weather. Protection should prevent the build-up of snow or ice but does not require full enclosure.
Fire resistance test criteria are set out in Appendix C. Standards of performance are summarised in Table C1.
Fire doors between the garage and dwellinghouse to have a minimum fire resistance of E30 Sa and be fitted with a self-closing device
Wall and any floor between the garage and dwellinghouse to have a minimum fire resistance of REI 30 from the garage side
The door opening threshold should be a minimum of 100mm above garage floor or
Floor to fall away from door to the outside
See paras 5.6 and 5.7
Elements of structure such as structural frames, beams, columns, loadbearing walls (internal and external), floor structures and gallery structures should have, as a minimum, the fire resistance given in Appendix B, Table B3.
If one element of structure supports or stabilises another, as a minimum the supporting element should have the same fire resistance as the other element.
If a garage is attached to or forms an integral part of a dwellinghouse, the garage should be separated from the rest of the dwellinghouse by fire resisting construction (minimum REI 30) (Diagram 5.1).
Elements of structure such as structural frames, beams, columns, loadbearing walls (internal and external), floor structures and gallery structures should have, as a minimum, the fire resistance given in Appendix B, Table B3.
NOTE: If one element of structure supports or stabilises another, as a minimum the supporting element should have the same fire resistance as the other element.
In a converted building with a maximum of three storeys, a minimum REI 30 fire resistance could be accepted for elements of structure if the means of escape conform to the provisions of Section 3.
In a converted building with four or more storeys, the full standard of fire resistance given in Appendix B is necessary.
An uninsulated glazed screen may be incorporated in the enclosure to a protected shaft between a stair and a lobby or corridor entered from the stair. The enclosure must conform to Diagram 7.2 and meet all of the following conditions.
a. The standard of fire resistance required for the protected stairway is not more than REI 60.
b. The glazed screen complies with the following.
i. It achieves a minimum rating of E 30.
ii. It complies with the guidance on limits on areas of uninsulated glazing in Appendix B, Table B5.
c. The lobby or corridor is enclosed with fire resisting construction achieving a minimum rating of REI 30.
Compartment walls forming a separated part of a building should run the full height of the building in a continuous vertical plane.
Separated parts can be assessed independently to determine the appropriate standard of fire resistance in each. The two separated parts can have different standards of fire resistance.
Further information on fire resisting ductwork is given in the ASFP Blue Book.
The wall of a flue, duct containing flues or appliance ventilation duct(s) should have a fire resistance (REI) that is at least half of any compartment wall or compartment floor it passes through or is built into (Diagram 9.5).
Provide a proprietary, tested sealing system that will maintain the fire resistance of the wall, floor or cavity barrier.
a. Flue passing through compartment wall or floor
b. Flue built into compartment wall
Flue walls should have a fire resistance of at least one half of that required for the compartment wall or floor and be of class A1construction.
In each case flue walls should have a fire resistance of at least one half of that required for the compartment wall and be of class A1 construction.
See para 9.23
Performance of the resistance of roofs to external fire exposure is measured in terms of penetration through the roof construction and the spread of flame over its surface.
Common to all of the provisions of Part B of the Building Regulations is the property of fire
resistance. Fire resistance is a measure of one or more of the following.
a. Resistance to collapse (loadbearing capacity), which applies to loadbearing elements only,
denoted R in the European classification of the resistance to fire performance.
b. Resistance to fire penetration (integrity), denoted E in the European classification of the
resistance to fire performance.
c. Resistance to the transfer of excessive heat (insulation), denoted I in the European
classification of the resistance to fire performance.
The fire resistance necessary for different circumstances is set out in the following tables.
a. Table B3 gives the specific requirements for each element of structure.
b. Table B4 sets out the minimum periods of fire resistance for elements of structure.
c. Table B5 sets out limitations on the use of uninsulated fire resisting glazed elements.
All fire doorsets should have the performance shown in Table C1, based on one of the following.
a. Fire resistance in terms of integrity, for a period of minutes, when tested to BS 476-22, e.g. FD 30.
A suffix (S) is added for doorsets where restricted smoke leakage at ambient temperatures is
needed.
b. As determined with reference to Commission Decision 2000/367/EC regarding the
classification of the resistance to fire performance of construction products, construction
works and parts thereof. All fire doorsets should be classified in accordance with BS EN 13501-2,
tested to the relevant European method from the following.
i. BS EN 1634-1.
ii. BS EN 1634-2.
iii. BS EN 1634-3.
c. As determined with reference to European Parliament and Council Directive 95/16/EC (which
applies to lifts that permanently serve buildings and constructions and specified safety
components) on the approximation of laws of Member States relating to lifts (‘Lifts Directive’)
implementing the
Recommendations for the specification, design, construction, installation and maintenance of fire
doorsets constructed with non-metallic door leaves are given in BS 8214.
Guidance on timber fire resisting doorsets, in relation to the new European test standard, may be
found in Timber Fire Resisting Doorsets: Maintaining Performance Under the New European Test
Standard published by the Timber Research and Development Association (TRADA).
Guidance for metal doors is given in Code of Practice for Fire Resisting Metal Doorsets published by
the Door and Shutter Manufacturers’ Association (DSMA).
Two fire doorsets may be fitted in the same opening if each door is capable of closing the opening,
so the total fire resistance is the sum of their individual resistances. If the opening is provided as a
means of escape, both fire doorsets should be self-closing.
If one fire doorset is capable of being easily opened by hand and has a minimum of 30 minutes’ fire
resistance, the other fire doorset should comply with both of the following.
a. Be fitted with an automatic self-closing device.
b. Be held open by a fusible link.
fire risk assessment
The aim of this regulation is to ensure that the person responsible for the building has sufficient
information relating to fire safety to enable them to manage the building effectively. The aim of
regulation 38 will be achieved when the person responsible for the building has all the information
to enable them to do all of the following.
a. Understand and implement the fire safety strategy of the building.
b. Maintain any fire safety system provided in the building.
c. Carry out an effective fire risk assessment of the building.
Where Part B applies to existing buildings, particularly buildings of special architectural or historic interest for which the guidance in this document might prove too restrictive, some variation of the provisions in this document may be appropriate. In such cases, it is appropriate to assess the hazard and risk in the particular case and consider a range of fire safety features in that context.
If a lift delivers into a protected corridor or protected lobby serving sleeping accommodation and also serves a storey containing a high fire risk (such as a kitchen, communal areas, stores, etc.) then the lift should be separated from the high fire risk area(s) by a protected lobby or protected corridor (minimum REI 30).
fire safety - volume 1: dwellings. 2019 edition - for use in england
This approved document has been published in two volumes. Volume 1 deals solely with dwellings, including blocks of flats, while Volume 2 deals with all other types of building covered by the Building Regulations
fire safety - volume 2: buildings other than dwellings. 2019 edition - for use in england
In the Secretary of State’s view, requirement B2 is met by achieving a restricted spread of flame
over internal linings. The building fabric should make a limited contribution to fire growth,
including a low rate of heat release.
It is particularly important in circulation spaces, where linings may offer the main means by which
fire spreads and where rapid spread is most likely to prevent occupants from escaping.
Requirement B2 does not include guidance on the following.
a. Generation of smoke and fumes.
b. The upper surfaces of floors and stairs.
c. Furniture and fittings.
The external envelope of a building should not provide a medium for undue fire spread to
adjacent buildings or be readily ignited by fires in adjacent buildings. This intention can be met by
constructing external walls so that all of the following are satisfied.
a. The risk of ignition by an external source to the outside surface of the building is restricted.
b. The amount of thermal radiation that falls on a neighbouring building from window openings
and other unprotected areas in the building on fire is not enough to start a fire in the other
building.
c. Flame spread over the roof and/or fire penetration from external sources through the roof is
restricted.
The extent to which this is necessary depends on the use of the building and its position in relation
to adjacent buildings and therefore the site boundary.
This approved document has been published in two volumes. Volume 1 deals solely with dwellings, including blocks of flats, while Volume 2 deals with all other types of building covered by the Building Regulations
The provisions in this document have the following aims.
Requirement B1: When there is a fire, ensure both:
a. satisfactory means of sounding an alarm
b. satisfactory means of escape for people.
Requirement B2: Inhibit the spread of fire over internal linings of buildings.
Requirement B3: The building must be built such that all of the following are achieved in the event of a fire:
a. the premature collapse of the building is avoided
b. sufficient fire separation is provided within buildings and between adjoining buildings
c. automatic fire suppression is provided where necessary
d. the unseen spread of fire and smoke in cavities is restricted.
Requirement B4: Restrict both:
a. the potential for fire to spread over external walls and roofs (including compliance with regulations 6(4) and 7(2))
b. the spread of fire from one building to another.
Requirement B5: Ensure both:
a. satisfactory access for the fire service and its appliances
b. facilities in buildings to help firefighters save the lives of people in and around buildings.
Regulation 38: Provide fire safety information to building owners.
The records should include details of all of the following.
e. All of the following.
i. Fire detector heads.
ii. Smoke detector heads.
iii. Alarm call points.
iv. Detection/alarm control boxes.
v. Alarm sounders.
vi. Emergency communications systems.
vii. CCTV.
viii. Fire safety signage.
ix. Emergency lighting.
x. Fire extinguishers.
xi. Dry or wet fire mains and other firefighting equipment.
xii. Other interior facilities for the fire and rescue service.
xiii. Emergency control rooms.
xiv. Location of hydrants outside the building.
xv. Other exterior facilities for the fire and rescue service.
Paragraphs 3.6 to 3.23 deal with the means of escape within each flat. Paragraphs 3.25 to 3.89 deal with the means of escape in common areas of the building (including mixed use buildings in paragraphs 3.76 and 3.77). Guidance for live/work units is given in paragraph 3.24.
Every doorway or other exit providing access to a means of escape, other than exits in ordinary use (e.g. main entrances), should be distinctively and conspicuously marked by an exit sign in accordance with BS ISO 3864-1 and BS 5499-4. For this reason, blocks of flats with a single stair in regular use would not usually require any fire exit signage.
Advice on fire safety signs, including emergency escape signs, is given in the HSE publication Safety Signs and Signals: Guidance on Regulations.
Some buildings may require additional signs to comply with other legislation.
Cavities in the construction of a building provide a ready route for the spread of smoke and flame, which can present a greater danger as any spread is concealed. For the purpose of this document, a cavity is considered to be any concealed space.
Cavities in the construction of a building provide a ready route for the spread of smoke and flame, which can present a greater danger as any spread is concealed. For the purpose of this document, a cavity is considered to be any concealed space.
Except for doorsets listed in paragraph C12, all fire doorsets should be marked with one of the
following fire safety signs, complying with BS 5499-5, as appropriate.
a. To be kept closed when not in use – mark ‘Fire door keep shut’.
b. To be kept locked when not in use – mark ‘Fire door keep locked shut’.
c. Held open by an automatic release mechanism or free swing device – mark ‘Automatic fire door
keep clear’.
All fire doorsets should be marked on both sides, except fire doorsets to cupboards and service
ducts, which should be marked on the outside.
All fire doorsets, including to flat entrances and between a dwellinghouse and an integral garage,
should be fitted with a self-closing device, except for all of the following.
a. Fire doorsets to cupboards.
b. Fire doorsets to service ducts normally locked shut.
c. Fire doorsets within flats and dwellinghouses.
fire wall
External fire spread
B4.(1)The external walls of the building shall adequately resist the spread of fire over the walls and from one building to another, having regard to the height, use and position of the building.
(2)The roof of the building shall adequately resist the spread of fire over the roof and from one building to another, having regard to the use and position of the building.
Regulation 7 – Materials and workmanship
(1)Building work shall be carried out—
(a)with adequate and proper materials which—
(i)are appropriate for the circumstances in which they are used,
(ii)are adequately mixed or prepared, and
(iii)are applied, used or fixed so as adequately to perform the functions for which they are designed; and
(b)in a workmanlike manner.
(2)Subject to paragraph (3), building work shall be carried out so that materials which become part of an external wall, or specified attachment, of a relevant building are of European Classification A2-s1, d0 or A1, classified in accordance with BS EN 13501-1:2007+A1:2009 entitled “Fire classification of construction products and building elements. Classification using test data from reaction to fire tests” (ISBN 978 0 580 59861 6) published by the British Standards Institution on 30th March 2007 and amended in November 2009.
(3)Paragraph (2) does not apply to—
(a)cavity trays when used between two leaves of masonry;
(b)any part of a roof (other than any part of a roof which falls within paragraph (iv) of regulation 2(6))if that part is connected to an external wall;
(c)door frames and doors;
(d)electrical installations;
(e)insulation and water proofing materials used below ground level;
(f)intumescent and fire stopping materials where the inclusion of the materials is necessary to meet the requirements of Part B of Schedule 1;
(g)membranes;
(h)seals, gaskets, fixings, sealants and backer rods;
(i)thermal break materials where the inclusion of the materials is necessary to meet the thermal bridging requirements of Part L of Schedule 1; or
(j)window frames and glass.
(4)In this regulation—
(a)a “relevant building” means a building with a storey (not including roof-top plant areas or any storey consisting exclusively of plant rooms) at least 18 metres above ground level and which—
(i)contains one or more dwellings;
(ii)contains an institution; or
(iii)contains a room for residential purposes(excluding any room in a hostel, hotel or boarding house); and
(b)“above ground level” in relation to a storey means above ground level when measured from the lowest ground level adjoining the outside of a building to the top of the floor surface of the storey.
The external wall of a building should not provide a medium for fire spread if that is likely to be a risk to health and safety. Combustible materials and cavities in external walls and attachments to them can present such a risk, particularly in tall buildings. The guidance in this section is designed to reduce the risk of fire spread as well as the risk of ignition from flames coming from adjacent buildings.
This section provides guidance on resisting fire spread over external walls; however, it does not deal with fire resistance of external walls. An external wall may need fire resistance to meet the provisions of Section 3 (Means of escape – flats), Section 6 (Loadbearing elements of structure – flats), Section 11 (Resisting fire spread from one building to another) or Section 15 (Access to buildings for firefighting personnel – flats).
Best practice guidance for green walls (also called living walls) can be found in Fire Performance of Green Roofs and Walls, published by the Department for Communities and Local Government. Where regulation 7(2) applies, that regulation prevails over all the provisions in this paragraph.
The fire resistance of a wall depends on its distance from the relevant boundary (see Diagram 11.1). Separation distances are measured to boundaries to ensure that the location and design of buildings on adjoining sites have no influence on the building under consideration.
Area of fire resisting wall with materials more than 1mm thick and with a reaction to fire performance worse than class B-s3, d2 = a x b
Area of wall counted as unprotected area = 0.5a x b
Area of fire resisting wall with materials having a reaction to fire performance better than class B-s3, d2
See para 11.7
Parts of an external wall with less fire resistance than the appropriate amount given in Appendix B, Table B4, are called unprotected areas.
Where a fire resisting external wall has an external surface material that is worse than class B-s3, d2 and is more than 1mm thick, that part of the wall should be classified as an unprotected area equating to half its area (Diagram 11.4).
Unprotected areas should meet the conditions in Diagram 11.5, and the rest of the wall should be fire resisting from both sides.
External surface materials facing the boundary should be class B-s3, d2 or better.
Unprotected areas should not exceed the result given by one of the methods in paragraph 11.16, and the rest of the wall (if any) should be fire resisting but only from the inside of the building.
The external envelope of a building should not provide a medium for fire spread if it is likely to be a risk to health or safety. The use of combustible materials for cladding framework, or of combustible thermal insulation as an overcladding or in ventilated cavities, may present such a risk in tall buildings, even though the provisions for external surfaces in Diagram 40 may have been satisfied.
In a building with a storey 18m or more above ground level, insulation material used in ventilated cavities in the external wall construction should be of limited combustibility (see Appendix A). This restriction does not apply to masonry cavity wall construction which complies with Diagram 32 in Section 10. Advice on the use of thermal insulation material is given in the BRE Report Fire performance of external thermal insulation for walls of multi-storey buildings (BR 135, 1988).
Configurations of stairs and external wall
Fire resisting construction
Fire resisting construction of adjacent building enclosure of protected stairway
Non-fire resisting construction
See para 3.63
With some configurations of external wall, a fire in one part of a building could subject the external wall of a protected stairway to heat (for example, where the two are adjacent at an internal angle in the façade, as shown in Diagram 3.10).
a. CORRIDOR ACCESS WITHOUT DEAD ENDS
b. CORRIDOR ACCESS WITH DEAD ENDS
The central door may be omitted if maximum travel distance is not more than 15m.
1. The arrangements shown also apply to the top storey.
2. For further guidance on the fire rating of the fire doorsets from the corridor to the flat and/or stairway refer to Appendix C ,Table C1.
Fire doorset provided in accordance with paragraphs 3.50 to 3.53(An external wall vent or smoke shaft located anywhere in the shaded area)
See paras 3.27 and 3.36
Fire doors between the garage and dwellinghouse to have a minimum fire resistance of E30 Sa and be fitted with a self-closing device
Wall and any floor between the garage and dwellinghouse to have a minimum fire resistance of REI 30 from the garage side
The door opening threshold should be a minimum of 100mm above garage floor or
Floor to fall away from door to the outside
See paras 5.6 and 5.7
Elements of structure such as structural frames, beams, columns, loadbearing walls (internal and external), floor structures and gallery structures should have, as a minimum, the fire resistance given in Appendix B, Table B3.
To reduce the risk of fire spreading over the roof from one compartment to another, a 1500mm wide zone of the roof, either side of the wall, should have a covering classified as BROOF(t4), on a substrate or deck of a material rated class A2-s3, d2 or better, as set out in Diagram 5.2a.
Thermoplastic rooflights that, because of paragraph 12.7, are regarded as having a BROOF(t4) classification are not suitable for use in that zone.
a. ANY BUILDING OR COMPARTMENT
Roof covering over this distance to be designated BROOF(t4) rated on deck of material of class A2-s3, d2 or better. Roof covering and deck could be composite structure, e.g. profiled steel cladding.
Fire-stopping to be carried up to underside of roof covering, boarding or slab.
Roof covering to be designated BROOF(t4) rated for at least 1500mm either side of wall.
b. RESIDENTIAL (DWELLINGS) AND RESIDENTIAL (OTHER) A MAXIMUM OF 15M HIGH
Boarding (used as a substrate) or timber tiling battens may be carried over the wall provided that they are fully bedded in mortar (or other no less suitable material) where over the wall.
Thermoplastic insulation materials should not be carried over the wall.
Double-skinned insulated roof sheeting with a thermoplastic core should incorporate a band of material of class A2-s3, d2 at least 300mm wide centred over the wall.
Sarking felt may also be carried over the wall.
If roof support members pass through the wall, fire protection to these members for a distance of 1500mm on either side of the wall may be needed to delay distortion at the junction (see paragraph 5.9).
Double-skinned insulated roof sheeting should incorporate a band of material rated class A2-s3, d2 or better, a minimum of 300mm in width, centred over the wall.
If roof support members pass through the wall, fire protection to these members for a distance of 1500mm on either side of the wall may be needed to delay distortion at the junction (see paragraph 5.9).
Fire-stopping to be carried up to underside of roof covering, e.g. roof tiles.
Section X–X
Roof covering to be designated BROOF(t4) rated for at least this distance.
Roofing battens and sarking felt may be carried over the wall.
Fire-stopping to be carried up to underside of roof covering above and below sarking felt.
NOTES:
1. Fire-stopping should be carried over the full thickness of the wall.
2. Fire-stopping should be extended into any eaves.
3. The compartment wall does not necessarily need to be constructed of masonry.
c. ANY BUILDING OR COMPARTMENT
The wall should be extended up through the roof for a height of at least 375mm above the top surface of the adjoining roof covering.
Where there is a height difference of at least 375mm between two roofs or where the roof coverings on either side of the wall are BROOF(t4) rated, the height of the upstand/parapet wall above the highest roof may be reduced to 200mm.
See paras 5.12 to 5.15
Timber beams, joists, purlins and rafters may be built into or carried through a masonry or concrete compartment wall if the openings for them are both of the following.
a. As small as practicable.
b. Fire-stopped.
If trussed rafters bridge the wall, failure of the truss due to a fire in one compartment should not cause failure of the truss in another compartment.
Elements of structure such as structural frames, beams, columns, loadbearing walls (internal and external), floor structures and gallery structures should have, as a minimum, the fire resistance given in Appendix B, Table B3.
NOTE: If one element of structure supports or stabilises another, as a minimum the supporting element should have the same fire resistance as the other element.
All of the following should be provided as compartment walls and compartment floors and should have, as a minimum, the fire resistance given in Appendix B, Table B3.
a. Any floor (unless it is within a flat, i.e. between one storey and another within one individual dwelling).
b. Any wall separating a flat from another part of the building.
c. Any wall enclosing a refuse storage chamber.
d. Any wall common to two or more buildings.
At the junction with another compartment wall or an external wall, the fire resistance of the compartmentation should be maintained. Fire-stopping that meets the provisions in paragraphs 9.24 to 9.29 should be provided.
At the junction of a compartment floor and an external wall with no fire resistance, the external wall should be restrained at floor level. The restraint should reduce movement of the wall away from the floor if exposed to fire.
Compartment walls should be able to accommodate deflection of the floor, when exposed to fire, by either of the following means.
a. Between the wall and floor, provide a head detail that is capable of maintaining its integrity while deforming.
b. Design the wall so it maintains its integrity by resisting the additional vertical load from the floor above.
Where compartment walls are located within the middle half of a floor between vertical supports, the deflection may be assumed to be 40mm unless a smaller value can be justified by assessment. Outside this area, the limit can be reduced linearly to zero at the supports.
For steel beams that do not have the required fire resistance, reference should be made to SCI Publication P288.
The external wall of a protected shaft does not normally need to have fire resistance. Situations where there are provisions are given in paragraph 3.63 (external walls of protected stairways, which may also be protected shafts) and paragraphs 15.8 to 15.11 (firefighting shafts).
Openings in other parts of the enclosure to a protected shaft should be limited to the following.
a. If a wall common to two or more buildings forms part of the enclosure, only the following openings should be made in that wall.
i. A fire doorset providing a means of escape, which has the same fire resistance as the wall and is fitted in accordance with the provisions in Appendix C.
ii. The passage of a pipe that meets the provisions in Section 9.
b. Other parts of the enclosure (other than an external wall) should only have openings for any of the following.
i. Fire doorsets of the appropriate fire resistance, fitted in accordance with the provisions in Appendix C.
ii. The passage of pipes which meet the provisions in Section 9.
iii. Inlets to, outlets from and openings for a ventilation duct (if the shaft contains or serves as a ventilating duct), meeting the provisions in Section 9.
iv. The passage of lift cables into a lift machine room (if the shaft contains a lift). If the machine room is at the bottom of the shaft, the openings should be as small as practicable.
Timber beams, joists, purlins and rafters may be built into or carried through a masonry or concrete compartment wall if the openings for them are both of the following.
a. As small as practicable.
b. Fire-stopped.
If trussed rafters bridge the wall, failure of the truss due to a fire in one compartment should not cause failure of the truss in another compartment.
The wall of a flue, duct containing flues or appliance ventilation duct(s) should have a fire resistance (REI) that is at least half of any compartment wall or compartment floor it passes through or is built into (Diagram 9.5).
Provide a proprietary, tested sealing system that will maintain the fire resistance of the wall, floor or cavity barrier.
a. Flue passing through compartment wall or floor
b. Flue built into compartment wall
Flue walls should have a fire resistance of at least one half of that required for the compartment wall or floor and be of class A1construction.
In each case flue walls should have a fire resistance of at least one half of that required for the compartment wall and be of class A1 construction.
See para 9.23
fire-separating element
In the Secretary of State’s view, requirement B3 is met by achieving all of the following.
a. For defined periods, loadbearing elements of structure withstand the effects of fire without
loss of stability.
b. Compartmentation of buildings by fire resisting construction elements.
c. Automatic fire suppression is provided where it is necessary.
d. Protection of openings in fire-separating elements to maintain continuity of the fire separation.
e. Inhibition of the unseen spread of fire and smoke in cavities, in order to reduce the risk of
structural failure and spread of fire and smoke, where they pose a threat to the safety of people
in and around the building.
The extent to which any of these measures are necessary is dependent on the use of the building
and, in some cases, its size, and on the location of the elements of construction.
Basic information on the location of fire protection measures may be sufficient. An as-built plan of the building should be provided showing all of the following.
a. Escape routes – this should include exit capacity (i.e. the maximum allowable number of people for each storey and for the building).
b. Location of fire-separating elements (including cavity barriers in walk-in spaces).
c. Fire doorsets, fire doorsets fitted with a self-closing device and other doors equipped with relevant hardware.
d. Locations of fire and/or smoke detector heads, alarm call points, detection/alarm control boxes, alarm sounders, fire safety signage, emergency lighting, fire extinguishers, dry or wet fire mains and other firefighting equipment, and hydrants outside the building.
e. Any sprinkler systems, including isolating valves and control equipment.
f. Any smoke control systems, or ventilation systems with a smoke control function, including mode of operation and control systems.
g. Any high risk areas (e.g. heating machinery).
The records should include details of all of the following. d. All passive fire safety measures, including all of the following. e. All of the following.
a. The fire safety strategy, including all assumptions in the design of the fire safety systems (such as fire load). Any risk assessments or risk analysis.
b. All assumptions in the design of the fire safety arrangements for the management of the building.
c. All of the following.
i. Escape routes (including occupant load and capacity of escape routes).
ii. Any provision to enable the evacuation of disabled people.
iii. Escape strategy (e.g. simultaneous or phased).
iv. Muster points.
i. Compartmentation (i.e. location of fire-separating elements).
ii. Cavity barriers.
iii. Fire doorsets, including fire doorsets fitted with a self-closing device and other doors equipped with relevant hardware (e.g. electronic security locks).
iv. Duct dampers.
v. Fire shutters.
i. Fire detector heads.
ii. Smoke detector heads.
iii. Alarm call points.
iv. Detection/alarm control boxes.
v. Alarm sounders.
vi. Emergency communications systems.
vii. CCTV.
viii. Fire safety signage.
ix. Emergency lighting.
x. Fire extinguishers.
xi. Dry or wet fire mains and other firefighting equipment.
xii. Other interior facilities for the fire and rescue service.
xiii. Emergency control rooms.
xiv. Location of hydrants outside the building.
xv. Other exterior facilities for the fire and rescue service.
f. All active fire safety measures, including both of the following.
i. Sprinkler system(s) design, including isolating valves and control equipment.
ii. Smoke control system(s) (or heating, ventilation and air conditioning system with a smoke control function) design, including mode of operation and control systems.
g. Any high risk areas (e.g. heating machinery) and particular hazards.
h. Plans of the building as built, showing the locations of the above.
i. Both of the following.
i. Specifications of any fire safety equipment provided, including all of the following.
• Operational details.
• Operators’ manuals.
• Software.
• System zoning.
• Routine inspection, testing and maintenance schedules.
ii. Records of any acceptance or commissioning tests.
j. Any other details appropriate for the specific building.
The records should include details of all of the following.
d. All passive fire safety measures, including all of the following.
i. Compartmentation (i.e. location of fire-separating elements).
ii. Cavity barriers.
iii. Fire doorsets, including fire doorsets fitted with a self-closing device and other doors equipped with relevant hardware (e.g. electronic security locks).
iv. Duct dampers.
v. Fire shutters.
The records should include details of all of the following.
d. All passive fire safety measures, including all of the following.
i. Compartmentation (i.e. location of fire-separating elements).
A lift well connecting different compartments should form a protected shaft (see Section 7).
Lift wells should comply with one of the following conditions.
a. Be sited within the enclosures of a protected stairway.
b. Be enclosed with fire resisting construction (minimum REI 30) when in a position that might prejudice the means of escape.
Fire resisting construction enclosing these places should achieve minimum REI 30. These walls and floors are not compartment walls and compartment floors.
Stairs and service shafts connecting compartments should be protected to restrict the spread of fire between the compartments. These are called protected shafts. Walls or floors surrounding a protected shaft are considered to be compartment walls or compartment floors.
Every joint, imperfect fit and opening for services through a fire-separating element should be sealed with fire-stopping to ensure that the fire resistance of the element is not impaired. Fire-stopping delays the spread of fire and, generally, the spread of smoke as well.
If air handling ducts pass through fire-separating elements, the fire performance of the elements should be maintained using one or more of the following four methods. In most ductwork systems, a combination of the four methods is best.
a. Method 1 – thermally activated fire dampers.
b. Method 2 – fire resisting enclosures.
c. Method 3 – protection using fire resisting ductwork.
d. Method 4 – automatically activated fire and smoke dampers triggered by smoke detectors.
Where ducts pass between fire-separating elements to serve multiple flats or dwellings, fire dampers or fire and smoke dampers should be actuated by both of the following.
a. Smoke detector-controlled automatic release mechanisms.
b. Thermally actuated devices.
Both fire dampers and fire and smoke dampers should be all of the following.
a. Sited within the thickness of the fire-separating elements.
b. Securely fixed.
c. Sited such that, in a fire, expansion of the ductwork would not push the fire damper through the structure.
Pipes passing through a fire-separating element, unless in a protected shaft, should meet one of the alternatives A, B or C below.
In addition to any other provisions in this section, both of the following conditions should be met.
a. Joints between fire-separating elements should be fire-stopped.
b. Openings through a fire resisting element for pipes, ducts, conduits or cable should be all of the following.
i. As few as possible.
ii. As small as practicable.
iii. Fire-stopped (allowing thermal movement in the case of a pipe or duct).
NOTE: The fire-stopping around fire dampers, fire resisting ducts, fire and smoke dampers and smoke control ducts should be in accordance with the manufacturer or supplier’s installation instructions.
The following guidance should be used when applying the fire resistance standards in Table B4.
a. If one element of structure supports or carries or gives stability to another, the fire resistance
of the supporting element should be no less than the minimum period of fire resistance for the
other element (whether that other element is loadbearing or not). In some circumstances, it
may be reasonable to vary this principle, for example:
i. if the supporting structure is in the open air and is not likely to be affected by the fire in
the building
ii. if the supporting structure is in a different compartment, with a fire-separating element
(that has the higher standard of fire resistance) between the supporting and the separated
structure
iii. if a plant room on the roof needs greater fire resistance than the elements of structure
that support it.
b. If an element of structure forms part of more than one building or compartment, that element
should be constructed to the standard of the higher of the relevant provisions.
c. If, due to the slope of the ground, one side of a basement is open at ground level (allowing
smoke to vent and providing access for firefighting) for elements of structure in that storey
it may be appropriate to adopt the standard of fire resistance that applies to above-ground
structures.
d. Although most elements of structure in a single storey building may not need fire resistance,
fire resistance is needed if one of the following applies to the element.
i. It is part of, or supports, an external wall, and there is provision in the guidance on
requirement B4 to limit the extent of openings and other unprotected areas in the wall.
ii. It is part of, or supports, a compartment wall, including a wall that is common to two or
more buildings.
iii. It supports a gallery.
fire-stop (Fire-stopping)
In buildings that include a ‘residential’ purpose (purpose groups 1 and 2) with a storey 11m or more in height (see Diagram D6 in Appendix D) balconies should meet either of the following conditions.
a. Only contain materials achieving class A1 or A2-s1, d0, except for any of the following.
i. Cavity trays when used between two leaves of masonry.
ii. Intumescent and fire-stopping materials where the inclusion of the materials is necessary to meet the requirements of Part B of Schedule 1 to the Building Regulations 2010.
iii. Membranes.
iv. Seals, gaskets, fixings, sealants and backer rods.
v. Thermal break materials where the inclusion of the materials is necessary to meet the thermal bridging requirements of Part L of Schedule 1 to the Building Regulations 2010.
vi. Any material achieving class A1fl or A2fl-s1 when it forms the top horizontal floor layer of a balcony and is provided with an imperforate substrate under it which extends to the full size of the class A1fl or A2fl-s1 material.
vii. Electrical installations.
viii. Fibre optic cables.
b. Achieve both of the following conditions.
Have an imperforate soffit which extends to the full area of the balcony, achieves a minimum REI 30 rating and is constructed of materials achieving class A2-s1, d0 or better.
ii. Materials achieving class B-s1, d0 or worse extending beyond the boundary of a single
compartment should include a band of material rated class A2-s1, d0 or better, a minimum of 300mm in width centred on that boundary line.
Where regulation 7(2) applies, that regulation prevails over all the provisions in this paragraph.
All of the following precautions should be taken to avoid the spread of smoke and fire to the protected stairway.
a. Transfer grilles should not be fitted in any wall, door, floor or ceiling of the stair enclosure.
b. Any duct passing through the stair enclosure should be rigid steel. Joints between the ductwork and stair enclosure should be fire-stopped.
c. Ventilation ducts supplying or extracting air directly to or from a protected stairway should not serve other areas as well.
d. Any system of mechanical ventilation which recirculates air and which serves both the stair and other areas should be designed to shut down on the detection of smoke within the system.
e. For ducted warm air heating systems, a room thermostat should be sited in the living room. It should be mounted at a height between 1370mm and 1830mm above the floor. The maximum setting should be 27°C.
NOTE: Ventilation ducts passing through compartment walls should comply with the guidance in Section 9.
For systems circulating air only within an individual flat, take all of the following precautions.
a. Transfer grilles should not be fitted in any wall, door, floor or ceiling of the enclosure.
b. Any duct passing through the enclosure should be rigid steel. Joints between the ductwork and enclosure should be fire-stopped.
c. Ventilation ducts serving the enclosure should not serve any other areas.
d. Any system of mechanical ventilation which recirculates air and which serves both the stair and other areas should be designed to shut down on the detection of smoke within the system.
e. For ducted warm air heating systems, a room thermostat should be sited in the living room. It should be mounted at a height between 1370mm and 1830mm above the floor. The maximum setting should be 27°C.
NOTE: Ventilation ducts passing through compartment walls should comply with the guidance in Section 9.
A compartment wall should achieve both of the following.
a. Meet the underside of the roof covering or deck, with fire-stopping to maintain the continuity of fire resistance.
b. Be continued across any eaves.
To reduce the potential for fire spread, cavity barriers should be provided for both of the following.
a. To divide cavities.
b. To close the edges of cavities.
Cavity barriers should not be confused with fire-stopping details (Section 9).
a. ANY BUILDING OR COMPARTMENT
Roof covering over this distance to be designated BROOF(t4) rated on deck of material of class A2-s3, d2 or better. Roof covering and deck could be composite structure, e.g. profiled steel cladding.
Fire-stopping to be carried up to underside of roof covering, boarding or slab.
Roof covering to be designated BROOF(t4) rated for at least 1500mm either side of wall.
b. RESIDENTIAL (DWELLINGS) AND RESIDENTIAL (OTHER) A MAXIMUM OF 15M HIGH
Boarding (used as a substrate) or timber tiling battens may be carried over the wall provided that they are fully bedded in mortar (or other no less suitable material) where over the wall.
Thermoplastic insulation materials should not be carried over the wall.
Double-skinned insulated roof sheeting with a thermoplastic core should incorporate a band of material of class A2-s3, d2 at least 300mm wide centred over the wall.
Sarking felt may also be carried over the wall.
If roof support members pass through the wall, fire protection to these members for a distance of 1500mm on either side of the wall may be needed to delay distortion at the junction (see paragraph 5.9).
Double-skinned insulated roof sheeting should incorporate a band of material rated class A2-s3, d2 or better, a minimum of 300mm in width, centred over the wall.
If roof support members pass through the wall, fire protection to these members for a distance of 1500mm on either side of the wall may be needed to delay distortion at the junction (see paragraph 5.9).
Fire-stopping to be carried up to underside of roof covering, e.g. roof tiles.
Section X–X
Roof covering to be designated BROOF(t4) rated for at least this distance.
Roofing battens and sarking felt may be carried over the wall.
Fire-stopping to be carried up to underside of roof covering above and below sarking felt.
NOTES:
1. Fire-stopping should be carried over the full thickness of the wall.
2. Fire-stopping should be extended into any eaves.
3. The compartment wall does not necessarily need to be constructed of masonry.
c. ANY BUILDING OR COMPARTMENT
The wall should be extended up through the roof for a height of at least 375mm above the top surface of the adjoining roof covering.
Where there is a height difference of at least 375mm between two roofs or where the roof coverings on either side of the wall are BROOF(t4) rated, the height of the upstand/parapet wall above the highest roof may be reduced to 200mm.
See paras 5.12 to 5.15
Cavity barriers should be tightly fitted to a rigid construction and mechanically fixed in position. If this is not possible (e.g. where a cavity barrier joins to slates, tiles, corrugated sheeting or similar materials) the junction should be fire-stopped.
NOTES:
1. Materials used to close the cavity in this arrangement do not need to achieve a specific performance in relation to fire resistance.
2. Domestic meter cupboards may be installed provided that the following conditions are met:
a. There are no more than two cupboards per dwelling
b. The openings in the outer wall leaf are not bigger than 800X500mm for each cupboard
c. The inner leaf is not penetrated except by a sleeve not more than 80X80mm, which is fire-stopped.
3. Materials achieving class B-s3, d2 or worse may be placed within the cavity.
See para 5.18
Timber beams, joists, purlins and rafters may be built into or carried through a masonry or concrete compartment wall if the openings for them are both of the following.
a. As small as practicable.
b. Fire-stopped.
If trussed rafters bridge the wall, failure of the truss due to a fire in one compartment should not cause failure of the truss in another compartment.
At the junction with another compartment wall or an external wall, the fire resistance of the compartmentation should be maintained. Fire-stopping that meets the provisions in paragraphs 9.24 to 9.29 should be provided.
Timber beams, joists, purlins and rafters may be built into or carried through a masonry or concrete compartment wall if the openings for them are both of the following.
a. As small as practicable.
b. Fire-stopped.
If trussed rafters bridge the wall, failure of the truss due to a fire in one compartment should not cause failure of the truss in another compartment.
Fire-stopping (same resistance as compartment)
Cavity barriers
NOTE:
1. See paragraph 8.5
See para 8.2
To reduce the potential for fire spread, cavity barriers should be provided for both of the following.
a. To divide cavities.
b. To close the edges of cavities.
See Diagram 8.1. Cavity barriers should not be confused with fire-stopping details (Section 9).
NOTES:
1. Materials used to close the cavity in this arrangement do not need to achieve a specific performance in relation to fire resistance.
2. Domestic meter cupboards may be installed provided that the following conditions are met:
a. There are no more than two cupboards per dwelling
b. The openings in the outer wall leaf are not bigger than 800X500mm for each cupboard
c. The inner leaf is not penetrated except by a sleeve not more than 80X80mm, which is fire-stopped.
3. Materials achieving class B-s3, d2 or worse may be placed within the cavity.
See para 8.3
The insulation should make contact with both skins of sheeting. See also Diagram 5.2a regarding the need for fire-stopping where such roofs pass over the top of a compartment wall.
See para 8.7
In divided corridors (paragraph 3.25 and following) with cavities, fire-stopping should be provided to prevent alternative escape routes being affected by fire and/or smoke.
NOTES:
1. The enclosure should meet all of the following conditions.
a. Be bounded by a compartment wall or floor, an outside wall, an intermediate floor or a casing(see specification at 2 below).
b. Have internal surfaces (except framing members)of class B-s3, d2 or better.
Note: when a classification includes ‘s3, d2’, this means that there is no limit set for smoke production and/or flaming droplets/particles).
c. Not have an access panel which opens into a circulation space or bed room.
d. Be used only for drainage or water supply or vent pipes for a drainage system.
2.The casing should meet all the following conditions.
a. Be imperforate except for an opening for a pipe
or an access panel.
b. Not be of sheet metal.
c. Not have fire resistance less than E 30 (including any access panel).
3.The opening for a pipe, in either the element of structure or the casing, should be as small as possible and fire-stopped around the pipe.
See para 9.4 and Table 9.1
Every joint, imperfect fit and opening for services through a fire-separating element should be sealed with fire-stopping to ensure that the fire resistance of the element is not impaired. Fire-stopping delays the spread of fire and, generally, the spread of smoke as well.
NOTES:
1.Make the opening in the structure as small as possible and provide fire-stopping between pipe and structure.
2.See Table 9.1 for materials specification.
3. The sleeve should be class A1 rated.
See para 9.5
In addition to any other provisions in this section, both of the following conditions should be met.
a. Joints between fire-separating elements should be fire-stopped.
b. Openings through a fire resisting element for pipes, ducts, conduits or cable should be all of the following.
i. As few as possible.
ii. As small as practicable.
iii. Fire-stopped (allowing thermal movement in the case of a pipe or duct).
NOTE: The fire-stopping around fire dampers, fire resisting ducts, fire and smoke dampers and smoke control ducts should be in accordance with the manufacturer or supplier’s installation instructions.
Materials used for fire-stopping should be reinforced with (or supported by) materials rated class A2-s3, d2 or better to prevent displacement in both of the following cases.
a. Where the unsupported span is greater than 100mm.
b. Where non-rigid materials are used (unless subjected to appropriate fire resistance testing to show their suitability).
Proprietary, tested fire-stopping and sealing systems are available and may be used. Different materials suit different situations and not all are suitable in every situation.
Other fire-stopping materials include the following. a. Cement mortar. b. Gypsum-based plaster. c. Cement-based or gypsum-based vermiculite/perlite mixes. d. Glass fibre, crushed rock, blast furnace slag or ceramic-based products (with or without resin binders). e. Intumescent mastics. These may be used in situations appropriate to the particular material. Not all materials will be suitable in every situation.
Where a proprietary sealing system is not used, fire-stop around the pipe, keeping the opening for the pipe as small as possible. The nominal internal diameter of the pipe should not exceed the relevant dimension given in Table 9.1. The diameter given in Table 9.1 for pipes of specification (b) used in situation 2 or 3 assumes that the pipes are part of an above-ground drainage system and are enclosed as shown in Diagram 9.1. If they are not, the smaller diameter given for situation 5 should be used.
firefighting lift
Minimum fire resistance REI60 from both sides with E30 Sa fire doors
Minimum fire resistance REI 120 from accommodation side and REI60 from inside the shaft with E60 Sa fire doors
NOTES:
1.Outlets from a fire main should be located in the firefighting lobby or, in the case of a shaft serving flats, in the firefighting stairway (see Diagram b).
2.Smoke control should be provided in accordance with BS9999 or, where the firefighting shaft only serves flats, the provisions for smoke control given in paragraph 3.49 may be followed instead.
3.A firefighting lift is required if the building has a floor more than 18m above, or more than 10m below, fire service vehicle access level.
4.This diagram is only to illustrate the basic components and is not meant to represent the only acceptable layout. The firefighting shaft should be constructed generally in accordance with section 6 of BS 9999.
5.For the minimum fire resistance of lift doors see Table C1.
See paras 15.2,15.8 and 15.9
Minimum fire resistance REI60 from both sides with E30 Sa fire doors
Minimum fire resistance REI 120 from accommodation side and REI60 from inside the shaft with E60 Sa fire doors
NOTES:
1.Outlets from a fire main should be located in the firefighting lobby or, in the case of a shaft serving flats, in the firefighting stairway (see Diagram b).
2.Smoke control should be provided in accordance with BS9999 or, where the firefighting shaft only serves flats, the provisions for smoke control given in paragraph 3.49 may be followed instead.
3.A firefighting lift is required if the building has a floor more than 18m above, or more than 10m below, fire service vehicle access level.
4.This diagram is only to illustrate the basic components and is not meant to represent the only acceptable layout. The firefighting shaft should be constructed generally in accordance with section 6 of BS 9999.
5.For the minimum fire resistance of lift doors see Table C1.
See paras 15.2,15.8 and 15.9
A firefighting lift installation includes all of the following.
a. Lift car.
b. Lift well.
c. Lift machinery space.
d. Lift control system.
e. Lift communications system.
The lift shaft should be constructed in accordance with Section 6 of BS 9999.
Firefighting lift installations should conform to BS EN 81-72 and BS EN 81-20.
A firefighting lift installation includes all of the following.
a. Lift car.
b. Lift well.
c. Lift machinery space.
d. Lift control system.
e. Lift communications system.
The lift shaft should be constructed in accordance with Section 6 of BS 9999.
Firefighting lift installations should conform to BS EN 81-72 and BS EN 81-20.
The fire and rescue service should be able to manually open and close rolling shutters without the use of a ladder.
A building with a storey more than 18m above the fire and rescue service vehicle access level should have one or more firefighting shafts, each containing a firefighting lift (Diagram 15.1). The number and location of firefighting shafts should comply with paragraphs 15.4 to 15.7. Firefighting shafts are not required to serve a basement that is not large or deep enough to need one (see paragraph 15.3 and Diagram 15.2).
A building with a storey more than 18m above the fire and rescue service vehicle access level should have one or more firefighting shafts, each containing a firefighting lift (Diagram 15.1). The number and location of firefighting shafts should comply with paragraphs 15.4 to 15.7. Firefighting shafts are not required to serve a basement that is not large or deep enough to need one (see paragraph 15.3 and Diagram 15.2).
A building with basement storeys should have firefighting shafts in accordance with the following.
a. There is a basement more than 10m below the fire and rescue service vehicle access level. The firefighting shafts should contain firefighting lifts.
b. There are two or more basement storeys, each with a minimum area of 900m2. The firefighting shafts do not need to include firefighting lifts.
The building’s height and size determine whether firefighting shafts also serve upper storeys.
A building with basement storeys should have firefighting shafts in accordance with the following.
a. There is a basement more than 10m below the fire and rescue service vehicle access level. The firefighting shafts should contain firefighting lifts.
b. There are two or more basement storeys, each with a minimum area of 900m2. The firefighting shafts do not need to include firefighting lifts.
The building’s height and size determine whether firefighting shafts also serve upper storeys.
Firefighting stairs and firefighting lifts should be approached from either of the following.
a. A firefighting lobby.
b. A protected corridor or protected lobby that complies with the following guidance.
i. Means of escape (Section 3).
ii. Compartmentation (Section 7).
Both the stair and lobby of the firefighting shaft should be provided with a means of venting smoke and heat (see clause 27.1 of BS 9999).
Only services associated with the firefighting shaft, such as ventilation systems and lighting for the firefighting shafts, should pass through or be contained within the firefighting shaft.
Doors of a firefighting lift landing should be a maximum of 7.5m from the door to the firefighting stair (Diagram 15.1).
Firefighting stairs and firefighting lifts should be approached from either of the following.
a. A firefighting lobby.
b. A protected corridor or protected lobby that complies with the following guidance.
i. Means of escape (Section 3).
ii. Compartmentation (Section 7).
Both the stair and lobby of the firefighting shaft should be provided with a means of venting smoke and heat (see clause 27.1 of BS 9999).
Only services associated with the firefighting shaft, such as ventilation systems and lighting for the firefighting shafts, should pass through or be contained within the firefighting shaft.
Doors of a firefighting lift landing should be a maximum of 7.5m from the door to the firefighting stair (Diagram 15.1).
The records should include details of all of the following.
e. All of the following.
i. Fire detector heads.
ii. Smoke detector heads.
iii. Alarm call points.
iv. Detection/alarm control boxes.
v. Alarm sounders.
vi. Emergency communications systems.
vii. CCTV.
viii. Fire safety signage.
ix. Emergency lighting.
x. Fire extinguishers.
xi. Dry or wet fire mains and other firefighting equipment.
xii. Other interior facilities for the fire and rescue service.
xiii. Emergency control rooms.
xiv. Location of hydrants outside the building.
xv. Other exterior facilities for the fire and rescue service.
A passenger lift serving any storey more than 4.5m above ground level should be in either of the following.
a. The enclosure to the protected stairway, as described in paragraph 2.5.
b. A fire resisting lift shaft (minimum REI 30).
A passenger lift serving any storey more than 4.5m above ground level should be in either of the following.
a. The enclosure to the protected stairway, as described in paragraph 2.5.
b. A fire resisting lift shaft (minimum REI 30).
A lift well connecting different compartments should form a protected shaft (see Section 7).
A lift well connecting different compartments should form a protected shaft (see Section 7).
In basements and enclosed car parks, the lift should be within the enclosure of a protected stairway. Otherwise, the lift should be approached only via a protected lobby or protected corridor (minimum REI 30).
In basements and enclosed car parks, the lift should be within the enclosure of a protected stairway. Otherwise, the lift should be approached only via a protected lobby or protected corridor (minimum REI 30).
If a lift delivers into a protected corridor or protected lobby serving sleeping accommodation and also serves a storey containing a high fire risk (such as a kitchen, communal areas, stores, etc.) then the lift should be separated from the high fire risk area(s) by a protected lobby or protected corridor (minimum REI 30).
If a lift delivers into a protected corridor or protected lobby serving sleeping accommodation and also serves a storey containing a high fire risk (such as a kitchen, communal areas, stores, etc.) then the lift should be separated from the high fire risk area(s) by a protected lobby or protected corridor (minimum REI 30).
Lift machine rooms should be sited over the lift well where possible. Where buildings or part of a building with only one stairway make this arrangement impractical, the lift machine room should be sited outside the protected stairway.
Lift machine rooms should be sited over the lift well where possible. Where buildings or part of a building with only one stairway make this arrangement impractical, the lift machine room should be sited outside the protected stairway.
Lift wells should comply with one of the following conditions.
a. Be sited within the enclosures of a protected stairway.
b. Be enclosed with fire resisting construction (minimum REI 30) when in a position that might prejudice the means of escape.
Lift wells should comply with one of the following conditions.
a. Be sited within the enclosures of a protected stairway.
b. Be enclosed with fire resisting construction (minimum REI 30) when in a position that might prejudice the means of escape.
Guidance on the control of flame spread is given in the following sections.
a. Stairs and landings: Sections 2 and 3 (escape stairs) and Section 15 (firefighting shafts).
b. Exposed surfaces above fire-protecting suspended ceilings: Section 8.
c. Enclosures to above-ground drainage system pipes: Section 9.
Openings should be limited to the following.
a. Fire doorsets with a minimum E 30 rating, fitted in accordance with Appendix C.
b. The passage of pipes that follow the provisions in Section 9.
c. The passage of cables or conduits containing one or more cables.
d. Openings fitted with a suitably mounted and appropriate fire damper.
e. Ducts that are either of the following.
i. Fire resisting (minimum E 30).
ii. Fitted with a suitably mounted and appropriate fire damper where they pass through the cavity barrier.
NOTE: For further guidance on openings in cavity barriers see Section 9.
All fire doorsets should have the performance shown in Table C1, based on one of the following.
a. Fire resistance in terms of integrity, for a period of minutes, when tested to BS 476-22, e.g. FD 30.
A suffix (S) is added for doorsets where restricted smoke leakage at ambient temperatures is
needed.
b. As determined with reference to Commission Decision 2000/367/EC regarding the
classification of the resistance to fire performance of construction products, construction
works and parts thereof. All fire doorsets should be classified in accordance with BS EN 13501-2,
tested to the relevant European method from the following.
i. BS EN 1634-1.
ii. BS EN 1634-2.
iii. BS EN 1634-3.
c. As determined with reference to European Parliament and Council Directive 95/16/EC (which
applies to lifts that permanently serve buildings and constructions and specified safety
components) on the approximation of laws of Member States relating to lifts (‘Lifts Directive’)
implementing the
Except for doorsets listed in paragraph C12, all fire doorsets should be marked with one of the
following fire safety signs, complying with BS 5499-5, as appropriate.
a. To be kept closed when not in use – mark ‘Fire door keep shut’.
b. To be kept locked when not in use – mark ‘Fire door keep locked shut’.
c. Held open by an automatic release mechanism or free swing device – mark ‘Automatic fire door
keep clear’.
All fire doorsets should be marked on both sides, except fire doorsets to cupboards and service
ducts, which should be marked on the outside.
The following fire doorsets are not required to comply with paragraph C11.
a. Doors to and within flats and dwellinghouses.
b. Bedroom doors in ‘residential (other)’ (purpose group 2(b)) premises.
c. Lift entrance/landing doors.
firefighting lobby
Minimum fire resistance REI60 from both sides with E30 Sa fire doors
Minimum fire resistance REI 120 from accommodation side and REI60 from inside the shaft with E60 Sa fire doors
NOTES:
1.Outlets from a fire main should be located in the firefighting lobby or, in the case of a shaft serving flats, in the firefighting stairway (see Diagram b).
2.Smoke control should be provided in accordance with BS9999 or, where the firefighting shaft only serves flats, the provisions for smoke control given in paragraph 3.49 may be followed instead.
3.A firefighting lift is required if the building has a floor more than 18m above, or more than 10m below, fire service vehicle access level.
4.This diagram is only to illustrate the basic components and is not meant to represent the only acceptable layout. The firefighting shaft should be constructed generally in accordance with section 6 of BS 9999.
5.For the minimum fire resistance of lift doors see Table C1.
See paras 15.2,15.8 and 15.9
Firefighting stairs and firefighting lifts should be approached from either of the following.
a. A firefighting lobby.
b. A protected corridor or protected lobby that complies with the following guidance.
i. Means of escape (Section 3).
ii. Compartmentation (Section 7).
Both the stair and lobby of the firefighting shaft should be provided with a means of venting smoke and heat (see clause 27.1 of BS 9999).
Only services associated with the firefighting shaft, such as ventilation systems and lighting for the firefighting shafts, should pass through or be contained within the firefighting shaft.
Doors of a firefighting lift landing should be a maximum of 7.5m from the door to the firefighting stair (Diagram 15.1).
In buildings designed for phased evacuation or progressive horizontal evacuation, if the lift well is not within the enclosures of a protected stairway, its entrance should be separated at every storey by a protected lobby (minimum REI 30).
In basements and enclosed car parks, the lift should be within the enclosure of a protected stairway. Otherwise, the lift should be approached only via a protected lobby or protected corridor (minimum REI 30).
If a lift delivers into a protected corridor or protected lobby serving sleeping accommodation and also serves a storey containing a high fire risk (such as a kitchen, communal areas, stores, etc.) then the lift should be separated from the high fire risk area(s) by a protected lobby or protected corridor (minimum REI 30).
Further guidance on the construction of firefighting stairs is given in Section 15 (see also paragraph 3.60). Dimensional constraints on the design of stairs are given in Approved Document K.
firefighting shaft
Flats
1. Within the enclosures of a protected entrance hall or protected landing, or within fire resisting separation shown in Section 3, Diagram 3.4.
2. Within either:
a. the enclosures of a protected stairway
b. fire resisting separation shown in Diagram 2.2.
3. Within fire resisting separation either:
a. shown in Diagram 2.4
b. described in paragraph 2.16b.
4. Existing window between an attached/integral garage and the dwellinghouse.
5. Adjacent to an external escape stair (see paragraph 2.17 and Diagram 2.7) or roof escape route (see paragraph 2.13).
6. Between residential/sleeping accommodation and a common escape route (corridor, lobby or stair).
7. Between a protected stairway(1)and either:
a. the accommodation
b. a corridor that is not a protected corridor other than in item 6 above.
8. Between either:
a. a protected stairway(1)and a protected lobby or protected corridor
b. accommodation and a protected lobby other than in item 6 above.
9. Between the accommodation and a protected corridor that forms a dead end,other than in item 6 above.
10.Between accommodation and any other corridor, or sub-dividing corridors,other than in item 6 above.
11. Beside an external escape route.
Table B5
see Table B3
Table B5
12. Beside an external escape stair (see paragraph 3.68 and Diagram 3.11) or roof escape route (see paragraph 3.30).
NOTES:
Items 1 and 8 apply also to single storey buildings.
Fire resisting glass should be marked with the name of the manufacturer and the name of the product.
Further guidance can be found in A Guide to Best Practice in the Specification and Use of Fire-resistant Glazed Systems published by the Glass and Glazing Federation.
1. If the protected stairway is also a protected shaft or a firefighting stair (see Section 15), there may be further
restrictions on the use of glazed elements.
2. Measured vertically from the landing floor level or the stair pitch line.
3. The 100mm limit is intended to reduce the risk of fire spreading from a floor covering.
Buildings with firefighting shafts should have fire mains provided in both of the following.
a. The firefighting stairs.
b. Where necessary, in protected stairways.
The criteria for providing firefighting shafts and fire mains are given in Section 15.
Buildings without firefighting shafts should be provided with fire mains where fire service vehicle access is not provided in accordance with paragraph 13.2(a). In these cases, the fire mains should be located within the protected stairway enclosure, with a maximum hose distance of 45m from the fire main outlet to the furthest point inside each flat, measured on a route suitable for laying a hose.
Minimum fire resistance REI60 from both sides with E30 Sa fire doors
Minimum fire resistance REI 120 from accommodation side and REI60 from inside the shaft with E60 Sa fire doors
NOTES:
1.Outlets from a fire main should be located in the firefighting lobby or, in the case of a shaft serving flats, in the firefighting stairway (see Diagram b).
2.Smoke control should be provided in accordance with BS9999 or, where the firefighting shaft only serves flats, the provisions for smoke control given in paragraph 3.49 may be followed instead.
3.A firefighting lift is required if the building has a floor more than 18m above, or more than 10m below, fire service vehicle access level.
4.This diagram is only to illustrate the basic components and is not meant to represent the only acceptable layout. The firefighting shaft should be constructed generally in accordance with section 6 of BS 9999.
5.For the minimum fire resistance of lift doors see Table C1.
See paras 15.2,15.8 and 15.9
All firefighting shafts should have fire mains with outlet connections and valves at every storey.
A building with a storey more than 18m above the fire and rescue service vehicle access level should have one or more firefighting shafts, each containing a firefighting lift (Diagram 15.1). The number and location of firefighting shafts should comply with paragraphs 15.4 to 15.7. Firefighting shafts are not required to serve a basement that is not large or deep enough to need one (see paragraph 15.3 and Diagram 15.2).
Buildings in which firefighting shafts should be provided,
showing which storeys need to be served >18m >10m
a. Any building The upper storeys in any building with a storey more than 18m above fire service vehicle access level
b. Any building The basement storeys in any building with a basement more than 10m below fire service vehicle access level
c. Any building The basement storey(s) in any building with two or more basements each exceeding 900m2
Fire service vehicle access level
Two or more basement storeys each exceeding 900m2
Extent of firefighting Extent of firefighting lift stair
NOTES:
1.Height excludes any top storey(s) consisting exclusively of plant rooms.
2.Firefighting shafts should serve all floors through which they pass.
See para 15.2
A building with basement storeys should have firefighting shafts in accordance with the following.
a. There is a basement more than 10m below the fire and rescue service vehicle access level. The firefighting shafts should contain firefighting lifts.
b. There are two or more basement storeys, each with a minimum area of 900m2. The firefighting shafts do not need to include firefighting lifts.
The building’s height and size determine whether firefighting shafts also serve upper storeys.
Firefighting shafts should serve all storeys through which they pass.
In buildings where a firefighting shaft is required, a minimum of two firefighting shafts should be provided in either of the following situations.
a. A building that has both of the following.
i. A storey with a floor area of 900m2 or more.
ii. A storey 18m or more above the fire and rescue service vehicle access level.
b. A building with a basement storey which is more than 900m2.
Firefighting shafts and protected stairways should be positioned such that every part of each storey more than 18m above the fire and rescue service vehicle access level complies with the maximum distances given in paragraph 15.7. Distances should be measured from the fire main outlet on a route suitable for laying a hose.
NOTE: If the internal layout is not known, the distance should be measured at two-thirds of the direct distance.
In any building, the hose laying distance should meet all of the following conditions.
a. A maximum of 60m from the fire main outlet in a firefighting shaft (see Diagram 15.3).
b. Additionally, where sprinklers have not been provided in accordance with Appendix E, the hose laying distance should be a maximum of 45m from a fire main outlet in a protected stairway (although this does not imply that the protected stairway needs to be designed as a firefighting shaft (see Diagram 15.3)).
Firefighting stairs and firefighting lifts should be approached from either of the following.
a. A firefighting lobby.
b. A protected corridor or protected lobby that complies with the following guidance.
i. Means of escape (Section 3).
ii. Compartmentation (Section 7).
Both the stair and lobby of the firefighting shaft should be provided with a means of venting smoke and heat (see clause 27.1 of BS 9999).
Only services associated with the firefighting shaft, such as ventilation systems and lighting for the firefighting shafts, should pass through or be contained within the firefighting shaft.
Doors of a firefighting lift landing should be a maximum of 7.5m from the door to the firefighting stair (Diagram 15.1).
Firefighting shafts should achieve a minimum fire resistance of REI 120. A minimum of REI 60 is acceptable for either of the following (see Diagram 15.1).
a. Constructions separating the firefighting shaft from the rest of the building.
b. Constructions separating the firefighting stair, firefighting lift shaft and firefighting lobby.
A lift well connecting different compartments should form a protected shaft (see Section 7).
In buildings designed for phased evacuation or progressive horizontal evacuation, if the lift well is not within the enclosures of a protected stairway, its entrance should be separated at every storey by a protected lobby (minimum REI 30).
In basements and enclosed car parks, the lift should be within the enclosure of a protected stairway. Otherwise, the lift should be approached only via a protected lobby or protected corridor (minimum REI 30).
Lift machine rooms should be sited over the lift well where possible. Where buildings or part of a building with only one stairway make this arrangement impractical, the lift machine room should be sited outside the protected stairway.
Further guidance on the construction of firefighting stairs is given in Section 15 (see also paragraph 3.60). Dimensional constraints on the design of stairs are given in Approved Document K.
Guidance on the control of flame spread is given in the following sections.
a. Stairs and landings: Sections 2 and 3 (escape stairs) and Section 15 (firefighting shafts).
b. Exposed surfaces above fire-protecting suspended ceilings: Section 8.
c. Enclosures to above-ground drainage system pipes: Section 9.
If a loadbearing wall is any of the following, guidance in other sections may also apply.
a. A compartment wall (including a wall common to two buildings): Section 7.
b. Enclosing a place of special fire hazard: Section 7.
c. Protecting a means of escape: Sections 2 and 3.
d. An external wall: Sections 10 and 11.
e. Enclosing a firefighting shaft: Section 15.
Any stair or other shaft passing directly from one compartment to another should be enclosed in a protected shaft. Protected shafts should be used for the following only, but may also include sanitary accommodation and washrooms.
a. Stairs.
b. Lifts.
c. Escalators.
d. Chutes.
e. Ducts.
f. Pipes.
g. Additional provisions apply for both of the following.
i. Protected shafts that are protected stairways: Sections 2 to 4.
ii. Stairs that are also firefighting stairs: Section 15.
The external wall of a protected shaft does not normally need to have fire resistance. Situations where there are provisions are given in paragraph 3.63 (external walls of protected stairways, which may also be protected shafts) and paragraphs 15.8 to 15.11 (firefighting shafts).
Openings in other parts of the enclosure to a protected shaft should be limited to the following.
a. If a wall common to two or more buildings forms part of the enclosure, only the following openings should be made in that wall.
i. A fire doorset providing a means of escape, which has the same fire resistance as the wall and is fitted in accordance with the provisions in Appendix C.
ii. The passage of a pipe that meets the provisions in Section 9.
b. Other parts of the enclosure (other than an external wall) should only have openings for any of the following.
i. Fire doorsets of the appropriate fire resistance, fitted in accordance with the provisions in Appendix C.
ii. The passage of pipes which meet the provisions in Section 9.
iii. Inlets to, outlets from and openings for a ventilation duct (if the shaft contains or serves as a ventilating duct), meeting the provisions in Section 9.
iv. The passage of lift cables into a lift machine room (if the shaft contains a lift). If the machine room is at the bottom of the shaft, the openings should be as small as practicable.
firefighting stair
Buildings with firefighting shafts should have fire mains provided in both of the following.
a. The firefighting stairs.
b. Where necessary, in protected stairways.
The criteria for providing firefighting shafts and fire mains are given in Section 15.
Buildings in which firefighting shafts should be provided,
showing which storeys need to be served >18m >10m
a. Any building The upper storeys in any building with a storey more than 18m above fire service vehicle access level
b. Any building The basement storeys in any building with a basement more than 10m below fire service vehicle access level
c. Any building The basement storey(s) in any building with two or more basements each exceeding 900m2
Fire service vehicle access level
Two or more basement storeys each exceeding 900m2
Extent of firefighting Extent of firefighting lift stair
NOTES:
1.Height excludes any top storey(s) consisting exclusively of plant rooms.
2.Firefighting shafts should serve all floors through which they pass.
See para 15.2
Firefighting stairs and firefighting lifts should be approached from either of the following.
a. A firefighting lobby.
b. A protected corridor or protected lobby that complies with the following guidance.
i. Means of escape (Section 3).
ii. Compartmentation (Section 7).
Both the stair and lobby of the firefighting shaft should be provided with a means of venting smoke and heat (see clause 27.1 of BS 9999).
Only services associated with the firefighting shaft, such as ventilation systems and lighting for the firefighting shafts, should pass through or be contained within the firefighting shaft.
Doors of a firefighting lift landing should be a maximum of 7.5m from the door to the firefighting stair (Diagram 15.1).
Firefighting shafts should achieve a minimum fire resistance of REI 120. A minimum of REI 60 is acceptable for either of the following (see Diagram 15.1).
a. Constructions separating the firefighting shaft from the rest of the building.
b. Constructions separating the firefighting stair, firefighting lift shaft and firefighting lobby.
Heat and smoke from basement fires vented via stairs can inhibit access for firefighting personnel. This may be reduced by providing smoke outlets, or smoke vents, which allow heat and smoke to escape from the basement levels to the open air. They can also be used by the fire and rescue service to let cooler air into the basements (Diagram 16.1).
In buildings designed for phased evacuation or progressive horizontal evacuation, if the lift well is not within the enclosures of a protected stairway, its entrance should be separated at every storey by a protected lobby (minimum REI 30).
In basements and enclosed car parks, the lift should be within the enclosure of a protected stairway. Otherwise, the lift should be approached only via a protected lobby or protected corridor (minimum REI 30).
If a lift delivers into a protected corridor or protected lobby serving sleeping accommodation and also serves a storey containing a high fire risk (such as a kitchen, communal areas, stores, etc.) then the lift should be separated from the high fire risk area(s) by a protected lobby or protected corridor (minimum REI 30).
Lift machine rooms should be sited over the lift well where possible. Where buildings or part of a building with only one stairway make this arrangement impractical, the lift machine room should be sited outside the protected stairway.
Section 7 provides guidance on avoiding the spread of fire between storeys. For a stair that is also a firefighting stair, guidance in Section 15 should be followed.
In buildings with more than three storeys above the ground storey, stairs may serve the flats and other occupancies if all of the following apply.
a. The flat is ancillary to the main use of the building.
b. The flat has an independent alternative escape route.
c. The stair is separated from occupancies on lower storeys by a protected lobby (minimum REI 30) at each of those storeys.
d. The stair enclosure has at least the same standard of fire resistance as the structural elements of the building (see Appendix B, Table B4); if the stair is a firefighting stair, it should comply with the provisions in Section 15 (see also paragraph 3.60).
e. Any automatic fire detection and alarm system fitted in the main part of the building also covers all flats.
f. Any security measures in any parts of the building do not prevent escape at all material times.
Further guidance on the construction of firefighting stairs is given in Section 15 (see also paragraph 3.60). Dimensional constraints on the design of stairs are given in Approved Document K.
Guidance on the control of flame spread is given in the following sections.
a. Stairs and landings: Sections 2 and 3 (escape stairs) and Section 15 (firefighting shafts).
b. Exposed surfaces above fire-protecting suspended ceilings: Section 8.
c. Enclosures to above-ground drainage system pipes: Section 9.
Any stair or other shaft passing directly from one compartment to another should be enclosed in a protected shaft. Protected shafts should be used for the following only, but may also include sanitary accommodation and washrooms.
a. Stairs.
b. Lifts.
c. Escalators.
d. Chutes.
e. Ducts.
f. Pipes.
g. Additional provisions apply for both of the following.
i. Protected shafts that are protected stairways: Sections 2 to 4.
ii. Stairs that are also firefighting stairs: Section 15.
fireplace recess
Guidance on door closing and ‘hold open’ devices for fire doorsets is set out in Appendix C.
Any door opening towards a corridor or a stair should be recessed to prevent its swing encroaching on the effective width.
first fix
Fixed ladders should not be provided as a means of escape for members of the public. They should only be provided where a conventional stair is impractical, such as for access to plant rooms which are not normally occupied.
flanking transmission
If one element of structure supports or stabilises another, as a minimum the supporting element should have the same fire resistance as the other element.
flat
While many of the provisions in this approved document for means of escape from flats are applicable to sheltered housing, the nature of the occupancy may necessitate some additional fire protection measures. The extent of such measures will depend on the form of the development. For example, a group of specially adapted bungalows or two storey flats, with few communal facilities, will not need to be treated differently from other single storey or two storey dwellinghouses or flats.
The fire detection and alarm systems in flats should connect to a central monitoring point or alarm
receiving centre. The systems should alert the warden or supervisor and identify the individual flat
where a fire has been detected.
Cavity barriers should be provided in accordance with Section 5 in dwellinghouses and Section 8 in flats.
To assist the fire service to identify each floor in a block of flats with a top storey more than 11m above ground level (see Diagram D6), floor identification signs and flat indicator signs should be provided.
For flats more than 4.5m above ground level, a balcony outside an alternative exit should be a common balcony meeting the conditions described in paragraph 3.22.
The internal arrangement of single storey or multi-storey flats should comply with paragraphs 3.15 to 3.17. Alternatively, the guidance in paragraphs 3.18 to 3.22 may be followed.
Where a flat is accessed via the common parts of a block of flats it may be necessary to provide a protected entrance hall to meet the provisions of paragraph 3.28 and Diagram 3.9.
A person escaping through the common area, if confronted by the effects of a fire in another flat, should be able to turn away from it and make a safe escape via an alternative route.
See para 3.18
Flat entrance
Kitchen area
Bath
The following paragraphs deal with means of escape from the entrance doors of flats to a final exit.
Flats may be served by an external stair if the provisions in paragraphs 3.66 to 3.69 are followed.
Access to an external escape stair may be via a flat roof, provided the flat roof meets the requirements of paragraph 3.30.
In buildings with a maximum of three storeys above the ground storey, stairs may serve both flats and other occupancies, provided that the stairs are separated from each occupancy by protected lobbies (minimum REI 30) at each storey.
flight
Any external escape stair should meet all of the following conditions (Diagram 2.7).
a. Doors to the stair should be fire resisting (minimum E 30), except for a single exit door from the building to the top landing of a downward-leading external stair.
b. Fire resisting construction (minimum RE 30) is required for the building envelope within the following zones, measured from the flights and landings of the external stair.
i. 1800mm horizontally.
ii. 9m vertically below.
iii. 1100mm above the top landing of the stair (except where the stair leads from basement to ground level).
c. Fire resisting construction (minimum RE 30) should be provided for any part of the building (including doors) within 1800mm of the escape route from the foot of the stair to a place of safety. This does not apply if there are alternative escape routes from the foot of the external escape stair.
d. Stairs more than 6m in height should be protected from adverse weather. Protection should prevent the build-up of snow or ice but does not require full enclosure.
e. Glazing in areas of fire resisting construction should be fixed shut and fire resisting (in terms of integrity, but not insulation) (minimum E 30).
Any external escape stair should meet all of the following conditions (Diagram 3.11).
a. Doors to the stair should be fire resisting (minimum E 30) and be fitted with a self-closing device, except for a single exit door from the building to the top landing of a downward-leading external stair, provided it is the only door onto the landing.
b. Fire resisting construction (minimum RE 30) is required for the building envelope within the following zones, measured from the flights and landings of the external stair.
i. 1800mm above and horizontally.
ii. 9m vertically below.
iii. 1100mm above the top landing of the stair (except where the stair leads from basement to ground level).
c. Fire resisting construction (minimum RE 30) should be provided for any part of the building (including doors) within 1800mm of the escape route from the foot of the stair to a place of safety. This does not apply if there are alternative escape routes from the foot of the external escape stair.
d. Glazing in areas of fire resisting construction should be fixed shut and fire resisting (in terms of integrity but not insulation) (minimum E 30).
e. Stairs more than 6m in height above ground level (e.g. where they are provided above a podium) should be protected from adverse weather. Protection should prevent the build-up of snow or ice but does not require full enclosure.
The flights and landings of escape stairs should be constructed of materials achieving class A2-s3, d2 or better in all of the following situations.
a. If the escape stair is the only stair in a building with more than three storeys.
b. If the escape stair is within a basement storey.
c. If the escape stair serves any storey that has a floor level more than 18m above ground or access level.
d. If the escape stair is an external escape stair, except where the stair connects the ground storey or ground level with a floor or flat roof a maximum of 6m above or below ground level.
e. If the escape stair is a firefighting stair.
Materials achieving class B-s3, d2 or worse may be added to the top horizontal surface, except on firefighting stairs.
Single steps on escape routes should be prominently marked. A single step on the line of a doorway is acceptable, subject to paragraph 3.107.
floating layer
Relevant metal composite materials are defined (in regulation 2(6)(c)) as any panel or sheet, having a thickness of no more than 10mm which is composed of a number of layers two or more of which are made of metal, alloy or metal compound and one or more of which is a substantial layer made of a material having a gross calorific value of more than 35MJ/kg when tested in accordance with BS EN ISO 1716. A substantial layer is defined as a layer which is at least 1mm thick or has a mass per unit area of at least 1kg/m².
Unprotected areas should meet the conditions in Diagram 11.5, and the rest of the wall should be fire resisting from both sides.
External surface materials facing the boundary should be class B-s3, d2 or better.
Unprotected areas should not exceed the result given by one of the methods in paragraph 11.16, and the rest of the wall (if any) should be fire resisting but only from the inside of the building.
Firefighting shafts should achieve a minimum fire resistance of REI 120. A minimum of REI 60 is acceptable for either of the following (see Diagram 15.1).
a. Constructions separating the firefighting shaft from the rest of the building.
b. Constructions separating the firefighting stair, firefighting lift shaft and firefighting lobby.
A fire doorset (minimum E 30 Sa) fitted with a self-closing device (and fire resisting screen, where required) should separate the dead-end portion of a common corridor from the rest of the corridor (Diagrams 3.7a, 3.8b and 3.8c).
The surface linings of walls and ceilings should meet the classifications in Table 4.1.
Cavity barriers are not required between double-skinned corrugated or profiled insulated roof sheeting, if the sheeting complies with all of the following.
a. The sheeting is rated class A2-s3, d2 or better.
b. Both surfaces of the insulating layer are rated class C-s3, d2 or better.
c. Both surfaces of the insulating layer make contact with the inner and outer skins of cladding (Diagram 8.4).
floor
The combined clear cross-sectional area of all smoke outlets should be a minimum of 1/40 of the area of the floor of the storey they serve.
Provide a proprietary, tested sealing system that will maintain the fire resistance of the wall, floor or cavity barrier.
floor 01
NOTES:
1. As an alternative to using the values in the table, the floor space factor may be determined by reference to actual data taken from similar premises. Where appropriate, the data should reflect the average occupant density at a peak trading time of year.
2. Where accommodation is not directly covered by the descriptions given, a reasonable value based on a similar use may be selected.
3. Where any part of the building is to be used for more than one type of accommodation, the most onerous factor(s) should be applied. Where the building contains different types of accommodation, the occupancy of each different area should be calculated using the relevant space factor.
4. For detailed guidance on appropriate floor space factors for concourses in sports grounds refer to Concourses published by the Football Licensing Authority.
5. Alternatively the occupant number may be taken as the number of fixed seats provided, if the occupants will normally be seated.
6. Shops excluding those under item 10, but including: supermarkets and department stores (main sales areas), shops for personal services, such as hairdressing, and shops for the delivery or collection of goods for cleaning, repair or other treatment or for members of the public themselves carrying out such cleaning, repair or other treatment.
7. Shops (excluding those in covered shopping complexes but including department stores) trading predominantly in furniture, floor coverings, cycles, prams, large domestic appliances or other bulky goods, or trading on a wholesale self-selection basis (cash and carry).
To assist the fire service to identify each floor in a block of flats with a top storey more than 11m above ground level (see Diagram D6), floor identification signs and flat indicator signs should be provided.
The combined clear cross-sectional area of all smoke outlets should be a minimum of 1/40 of the area of the floor of the storey they serve.
Air circulation systems which circulate air within an individual dwellinghouse with a floor more than
4.5m above ground level should meet the guidance given in paragraph 2.9.
A ramp forming part of an escape route should meet the provisions in Approved Document M. Any sloping floor or tier should have a pitch of not more than 35 degrees to the horizontal.
Fire doors between the garage and dwellinghouse to have a minimum fire resistance of E30 Sa and be fitted with a self-closing device
Wall and any floor between the garage and dwellinghouse to have a minimum fire resistance of REI 30 from the garage side
The door opening threshold should be a minimum of 100mm above garage floor or
Floor to fall away from door to the outside
See paras 5.6 and 5.7
If a floor is also a compartment floor, see Section 7.
Provide a proprietary, tested sealing system that will maintain the fire resistance of the wall, floor or cavity barrier.
floor 02
NOTES:
1. As an alternative to using the values in the table, the floor space factor may be determined by reference to actual data taken from similar premises. Where appropriate, the data should reflect the average occupant density at a peak trading time of year.
2. Where accommodation is not directly covered by the descriptions given, a reasonable value based on a similar use may be selected.
3. Where any part of the building is to be used for more than one type of accommodation, the most onerous factor(s) should be applied. Where the building contains different types of accommodation, the occupancy of each different area should be calculated using the relevant space factor.
4. For detailed guidance on appropriate floor space factors for concourses in sports grounds refer to Concourses published by the Football Licensing Authority.
5. Alternatively the occupant number may be taken as the number of fixed seats provided, if the occupants will normally be seated.
6. Shops excluding those under item 10, but including: supermarkets and department stores (main sales areas), shops for personal services, such as hairdressing, and shops for the delivery or collection of goods for cleaning, repair or other treatment or for members of the public themselves carrying out such cleaning, repair or other treatment.
7. Shops (excluding those in covered shopping complexes but including department stores) trading predominantly in furniture, floor coverings, cycles, prams, large domestic appliances or other bulky goods, or trading on a wholesale self-selection basis (cash and carry).
To assist the fire service to identify each floor in a block of flats with a top storey more than 11m above ground level (see Diagram D6), floor identification signs and flat indicator signs should be provided.
The combined clear cross-sectional area of all smoke outlets should be a minimum of 1/40 of the area of the floor of the storey they serve.
Air circulation systems which circulate air within an individual dwellinghouse with a floor more than
4.5m above ground level should meet the guidance given in paragraph 2.9.
A ramp forming part of an escape route should meet the provisions in Approved Document M. Any sloping floor or tier should have a pitch of not more than 35 degrees to the horizontal.
Fire doors between the garage and dwellinghouse to have a minimum fire resistance of E30 Sa and be fitted with a self-closing device
Wall and any floor between the garage and dwellinghouse to have a minimum fire resistance of REI 30 from the garage side
The door opening threshold should be a minimum of 100mm above garage floor or
Floor to fall away from door to the outside
See paras 5.6 and 5.7
If a floor is also a compartment floor, see Section 7.
At the junction of a compartment floor and an external wall with no fire resistance, the external wall should be restrained at floor level. The restraint should reduce movement of the wall away from the floor if exposed to fire.
Provide a proprietary, tested sealing system that will maintain the fire resistance of the wall, floor or cavity barrier.
flue box
Final exits should avoid outlets of basement smoke vents and openings to transformer chambers, refuse chambers, boiler rooms and similar risks.
fluepipe
NOTES:
1.There are restrictions on the use of plastic rooflights in the guidance to requirement B2 in Section 4.
2.Surrounding roof covering to be a material of class A2-s3, d3 or better for at least 3m distance.
3.Where Diagram 5.2a or 5.2b applies, rooflights should be at least 1500mm from the compartment wall.
See paras 12.5 and 12.6
The performance of rooflights is specified in a similar way to the performance of roof coverings. Plastic rooflights may also be used.
A pipe with a maximum nominal internal diameter of 160mm may be used with a sleeve made out of a high melting point metal, as shown in Diagram 9.2, if the pipe is made of one of the following.
a. Lead.
b. Aluminium.
c. Aluminium alloy.
d. Fibre-cement.
e. uPVC (pipes should also comply with either BS 4514 or BS 5255).
A high melting point metal means any metal (such as cast iron, copper or steel) which, if exposed to a temperature of 800°C, will not soften or fracture to the extent that flame or hot gas will pass through the wall of the pipe.
For the systems described in paragraph E5, both of the following apply if pumps are used to draw
water from two tanks.
a. Each pump should be able to draw water from either tank.
b. Any one pump, or either tank, should be able to be isolated.
The sprinkler water supplies should not be used as connections for other services or other fixed
firefighting systems.
following edge (of door)
People should be able to rapidly leave the area around the building. Direct access to a street, passageway, walkway or open space should be available. The route away from the building should comply with the following.
a. Be well defined.
b. If necessary, have suitable guarding.
Doors should be readily openable to avoid undue delay to people escaping. Doors on escape routes (both within and from the building) should comply with paragraphs 3.91 to 3.98. Guidance on door closing and ‘hold open’ devices for fire doorsets is set out in Appendix C.
NOTE: Paragraphs 3.91 to 3.98 do not apply to flat entrance doors.
In general, doors on escape routes (whether or not the doors are fire doorsets) should be either of the following.
a. Not fitted with a lock, latch or bolt fastenings.
b. Fitted only with simple fastenings that are all of the following.
i. Easy to operate; it should be apparent how to undo the fastening.
ii. Operable from the side approached by people escaping.
iii. Operable without a key.
iv. Operable without requiring people to manipulate more than one mechanism.
Doors may be fitted with hardware to allow them to be locked when rooms are empty.
If a secure door is operated by code or combination keypad, swipe or proximity card, biometric data, etc., a security mechanism override should be possible from the side approached by people escaping.
Electrically powered locks should return to the unlocked position in all of the following situations.
a. If the fire detection and alarm system operates.
b. If there is loss of power or system error.
c. If the security mechanism override is activated.
Security mechanism overrides for electrically powered locks should be a Type A call point, as described in BS 7273-4. The call point should be positioned on the side approached by people escaping. If the door provides escape in either direction, a call point should be installed on both sides of the door.
All doors on escape routes should be hung to meet both of the following conditions.
a. Open by a minimum of 90 degrees.
b. Open with a swing that complies with both of the following.
i. Is clear of any change of floor level, other than a threshold or single step on the line of the doorway.
ii. Does not reduce the effective width of any escape route across a landing.
Any door opening towards a corridor or a stair should be recessed to prevent its swing encroaching on the effective width.
Doors should contain vision panels in both of the following situations.
a. Where doors on escape routes divide corridors.
b. Where doors are hung to swing both ways.
Approved Document M contains guidance about vision panels in doors across accessible corridors and Approved Document K contains guidance about the safety of glazing.
Where revolving doors, automatic doors and turnstiles are placed across escape routes they should comply with one of the following.
a. They are automatic doors of the required width and comply with one of the following conditions.
i. Their failsafe system provides outward opening from any open position.
ii. They have a monitored failsafe system to open the doors if the mains electricity supply fails.
iii. They failsafe to the open position if the power fails.
b. Non-automatic swing doors of the required width are provided immediately adjacent to the revolving or automatic door or turnstile.
forms
The unprotected area of the external wall of a stairway forming a protected shaft may be disregarded for separation distance purposes
Roofs pitched at an angle of less than 70 degrees may be disregarded for separation distance purposes
Represents an unprotected area of not more than 1m2 which may consist of two or more smaller areas within an area of 1000mm X 1000mm
Represents an area of not more than 0.1m2
See para 11.11
Where a flat roof forms part of a means of escape, it should comply with all of the following.
a. It should be part of the same building from which escape is being made.
b. The route across the roof should lead to a storey exit or external escape route.
c. The part of the roof (including its supporting structure) forming the escape route, and any opening within 3m of the escape route, should be of fire resisting construction (minimum REI 30).
Where a flat roof forms part of a means of escape, it should comply with all of the following.
a. It should be part of the same building from which escape is being made.
b. The route across the roof should lead to a storey exit or external escape route.
c. The part of the roof (including its supporting structure) forming the escape route, and any opening within 3m of the escape route, should be of fire resisting construction (minimum REI 30).
Ancillary accommodation should not be located in, or entered from, a protected lobby or protected corridor forming the only common escape route on that storey.
A ramp forming part of an escape route should meet the provisions in Approved Document M. Any sloping floor or tier should have a pitch of not more than 35 degrees to the horizontal.
a. DIFFUSER FORMING PART OF CEILING
b. DIFFUSER IN FITTING BELOW AND NOT FORMING PART OF CEILING
See para 4.15
Cavity barriers in a stud wall or partition, or provided around openings, may be formed of any of the following.
a. Steel, a minimum of 0.5mm thick.
b. Timber, a minimum of 38mm thick.
c. Polythene-sleeved mineral wool, or mineral wool slab, under compression when installed in the cavity.
d. Calcium silicate, cement-based or gypsum-based boards, a minimum of 12mm thick.
These do not necessarily achieve the performance specified in paragraph 5.20.
NOTE: Cavity barriers provided around openings may be formed by the window or door frame, if the frame is constructed of steel or timber of the minimum thickness in (a) or (b), as appropriate.
If a garage is attached to or forms an integral part of a dwellinghouse, the garage should be separated from the rest of the dwellinghouse by fire resisting construction (minimum REI 30) (Diagram 5.1).
framed wall
External fire spread
B4.(1)The external walls of the building shall adequately resist the spread of fire over the walls and from one building to another, having regard to the height, use and position of the building.
(2)The roof of the building shall adequately resist the spread of fire over the roof and from one building to another, having regard to the use and position of the building.
Regulation 7 – Materials and workmanship
(1)Building work shall be carried out—
(a)with adequate and proper materials which—
(i)are appropriate for the circumstances in which they are used,
(ii)are adequately mixed or prepared, and
(iii)are applied, used or fixed so as adequately to perform the functions for which they are designed; and
(b)in a workmanlike manner.
(2)Subject to paragraph (3), building work shall be carried out so that materials which become part of an external wall, or specified attachment, of a relevant building are of European Classification A2-s1, d0 or A1, classified in accordance with BS EN 13501-1:2007+A1:2009 entitled “Fire classification of construction products and building elements. Classification using test data from reaction to fire tests” (ISBN 978 0 580 59861 6) published by the British Standards Institution on 30th March 2007 and amended in November 2009.
(3)Paragraph (2) does not apply to—
(a)cavity trays when used between two leaves of masonry;
(b)any part of a roof (other than any part of a roof which falls within paragraph (iv) of regulation 2(6))if that part is connected to an external wall;
(c)door frames and doors;
(d)electrical installations;
(e)insulation and water proofing materials used below ground level;
(f)intumescent and fire stopping materials where the inclusion of the materials is necessary to meet the requirements of Part B of Schedule 1;
(g)membranes;
(h)seals, gaskets, fixings, sealants and backer rods;
(i)thermal break materials where the inclusion of the materials is necessary to meet the thermal bridging requirements of Part L of Schedule 1; or
(j)window frames and glass.
(4)In this regulation—
(a)a “relevant building” means a building with a storey (not including roof-top plant areas or any storey consisting exclusively of plant rooms) at least 18 metres above ground level and which—
(i)contains one or more dwellings;
(ii)contains an institution; or
(iii)contains a room for residential purposes(excluding any room in a hostel, hotel or boarding house); and
(b)“above ground level” in relation to a storey means above ground level when measured from the lowest ground level adjoining the outside of a building to the top of the floor surface of the storey.
For the purposes of this requirement, a wall does not include any of the following.
a. Doors and door frames.
b. Window frames and frames in which glazing is fitted.
c. Architraves, cover moulds, picture rails, skirtings and similar narrow members.
d. Fireplace surrounds, mantle shelves and fitted furniture.
Elements of structure such as structural frames, beams, columns, loadbearing walls (internal and external), floor structures and gallery structures should have, as a minimum, the fire resistance given in Appendix B, Table B3.
Cavity barriers in a stud wall or partition, or provided around openings, may be formed of any of the following.
a. Steel, a minimum of 0.5mm thick.
b. Timber, a minimum of 38mm thick.
c. Polythene-sleeved mineral wool, or mineral wool slab, under compression when installed in the cavity.
d. Calcium silicate, cement-based or gypsum-based boards, a minimum of 12mm thick.
These do not necessarily achieve the performance specified in paragraph 5.20.
NOTE: Cavity barriers provided around openings may be formed by the window or door frame, if the frame is constructed of steel or timber of the minimum thickness in (a) or (b), as appropriate.
Elements of structure such as structural frames, beams, columns, loadbearing walls (internal and external), floor structures and gallery structures should have, as a minimum, the fire resistance given in Appendix B, Table B3.
NOTE: If one element of structure supports or stabilises another, as a minimum the supporting element should have the same fire resistance as the other element.
free area
Free area measured at right angles to air flow
Free area for louvred vent = a1+a2+a3+a4+a5
For some low rise buildings, the provisions in paragraphs 3.26 and 3.27 may be modified and the use of a single stair, protected in accordance with Diagram 3.9, may be permitted where all of the following apply.
a. The top storey of the building is a maximum of 11m above ground level.
b. No more than three storeys are above the ground storey.
c. The stair does not connect to a covered car park, unless the car park is open sided (as defined in Section 11 of Approved Document B Volume 2).
d. The stair does not serve offices, stores or other ancillary accommodation. If it does, they should be separated from the stair by a protected lobby or protected corridor (minimum REI 30) with a minimum 0.4m2 of permanent ventilation, or be protected from the ingress of smoke by a mechanical smoke control system.
NOTE: For refuse chutes and storage see paragraphs 3.55 to 3.58.
e. Either of the following is provided for the fire and rescue service.
i. A high-level openable vent with a free area of at least 1m2 at each storey.
ii. A single openable vent with a free area of at least 1m2 at the head of the stair, operable remotely at the fire and rescue service access level.
Smoke vents should comply with one of the following.
a. They should be located on an external wall with minimum free area of 1.5m2.
b. They should discharge into a vertical smoke shaft, closed at the base, that meets all of the following criteria.
i. The shaft should conform to the following conditions.
• Have a minimum cross-sectional area of 1.5m2 (minimum dimension 0.85m in any direction).
• Open at roof level, minimum 0.5m above any surrounding structures within 2m of it horizontally.
• Extend a minimum of 2.5m above the ceiling of the highest storey served by the shaft.
ii. The free area of all the following vents should be a minimum of 1m2 in the following places.
• From the corridor or lobby into the shaft.
• At the opening at the head of the shaft.
• At all internal locations within the shaft (e.g. safety grilles).
iii. The smoke shaft should be constructed from a class A1 material. All vents should either be a smoke leakage (Sa) rated fire doorset (see Appendix C, Table C1, item 2.e for minimum fire resistance) or fitted with a smoke control damper achieving the same period of fire resistance and designed to operate as described below. The shaft should be vertical from base to head, with a maximum of 4m at a maximum inclined angle of 30 degrees.
iv. If smoke is detected in the common corridor or lobby, both of the following should occur.
• Simultaneous opening of vents on the storey where the fire is located, at the top of the smoke shaft and to the stair.
• Vents from the corridors or lobbies on all other storeys should remain closed, even if smoke is subsequently detected on storeys other than where the fire is located.
A vent to the outside with a minimum free area of 1m2 should be provided from the top storey of the stair.
a. SMALL SINGLE STAIR BUILDING
*If smoke control is provided in the lobby, the travel distance can be increased to 7.5m maximum(see Diagram 3.7, example b).
b. SMALL SINGLE STAIR BUILDING WITH NO MORE THAN TWO FLATS PER STOREY
The door between stair and lobby should be free from security fastenings.
If the flats have protected entrance halls, the lobby between the common stair and flat entrance is not essential.
NOTES:
1. The arrangements shown also apply to the top storey.
2. If the travel distance across the lobby in diagram (a) exceeds 4.5m, Diagram 3.7 applies.
3. Where,in Diagram (b), the lobby between the common stair and the dwelling is omitted in smal lsingle stair buildings, an automatic opening vent with a free area of at least 1m2 is required at the top of the stair,which is operated automatically on detection of smoke at any storey in the stair.
4. For further guidance on the fire rating of the fire doorsets from the corridor to the flat and/or stairway refer to Appendix C, Table C1.
Fire resisting construction
Openable vent at high level for fire service use (1.0m2 minimum free area); see paragraph 3.28eSee para 3.28
Diagram 3.9
The free area of a smoke ventilator should be measured by either of the following.
a. The declared aerodynamic free area in accordance with BS EN 12101-2.
b. The total unobstructed cross-sectional area (geometric free area), measured in the plane where
the area is at a minimum and at right angles to the direction of air flow (Diagram D7).
gallery
NOTES:
1.In assembly buildings (purpose group 5), a gallery is included as a storey, but not if it is a loading gallery, fly gallery, stage grid, lighting bridge, or any gallery provided for similar purposes, or for maintenance and repair.
2.In other purpose group buildings, galleries are not counted as a storey.
3.For the definition of basement, see Appendix A.
A gallery should comply with one of the following.
a. It should be provided with an alternative exit.
b. It should be provided with an emergency escape window, as described in paragraph 2.10, where the gallery floor is a maximum of 4.5m above ground level.
c. It should meet all the conditions shown in Diagram 2.6.
NOTES:
1. This diagram does not apply where the gallery is provided with one of the following:
i. An alternative escape route
ii. An emergency escape window (where the gallery floor is not more than 4.5m above ground level).
2. Any cooking facilities within a room containing a gallery should comply with one of the following conditions:
i. Be enclosed with fire resisting construction
ii. Be remote from the stair to the gallery and positioned such that they do not prejudice escape from the gallery.
See para 2.15
NOTES:
1. This diagram does not apply where the gallery is provided with one of the following:
i. An alternative escape route
ii. An emergency escape window (where the gallery floor is not more than 4.5m above ground level).
2. Any cooking facilities within a room containing a gallery should comply with one of the following conditions:
i. Be enclosed with fire resisting construction
ii. Be remote from the stair to the gallery and positioned such that they do not prejudice escape from the gallery.
See para 3.13
A gallery should comply with one of the following.
a. It should be provided with an alternative exit.
b. It should be provided with an emergency escape window, as described in paragraph 3.6, where the gallery floor is a maximum of 4.5m above ground level.
c. It should meet the conditions shown in Diagram 3.1.
All doors on escape routes should be hung to meet both of the following conditions.
a. Open by a minimum of 90 degrees.
b. Open with a swing that complies with both of the following.
i. Is clear of any change of floor level, other than a threshold or single step on the line of the doorway.
ii. Does not reduce the effective width of any escape route across a landing.
Elements of structure such as structural frames, beams, columns, loadbearing walls (internal and external), floor structures and gallery structures should have, as a minimum, the fire resistance given in Appendix B, Table B3.
Elements of structure such as structural frames, beams, columns, loadbearing walls (internal and external), floor structures and gallery structures should have, as a minimum, the fire resistance given in Appendix B, Table B3.
NOTE: If one element of structure supports or stabilises another, as a minimum the supporting element should have the same fire resistance as the other element.
gateway points
Where Part B applies to existing buildings, particularly buildings of special architectural or historic interest for which the guidance in this document might prove too restrictive, some variation of the provisions in this document may be appropriate. In such cases, it is appropriate to assess the hazard and risk in the particular case and consider a range of fire safety features in that context.
Sprinkler systems installed in buildings can reduce the risk to life and significantly reduce the
degree of damage caused by fire within a building.
general
see Table B4
See Table C1
See Appendix C
NOTES:
1. BS EN 13501-2 Classification using data from fire resistance tests, excluding ventilation services.BS EN 13501-3
Classification using data from fire resistance tests on products and elements used in building service installations: fire resisting ducts and fire dampers. BS EN 13501-4 Classification using data from fire resistance tests on components of smoke control systems.
In the European classification:
‘R’ is the resistance to fire in terms of loadbearing capacity.
‘E’ is the resistance to fire in terms of integrity.
‘I’ is the resistance to fire in terms of insulation.
The national classifications do not automatically equate with the alternative classifications in the European column, therefore products cannot typically assume a European class unless they have been tested accordingly.
2. BS 476-20 for general principles,BS 476-21 for loadbearing elements,BS 476-22 for non-loadbearing elements,BS 476-23 for fire-protecting suspended ceilings and BS 476-24 for ventilation ducts.
3. Applies to loadbearing elements only (see paragraph B19).
4. Guidance on increasing the fire resistance of existing timber floors is given in BRE Digest 208.
5. Only if a suspended ceiling meets the appropriate provisions should it be relied on to add to the fire resistance of the floor.
6. Such walls may contain areas that do not need to be fire resisting (unprotected areas). See Section 11.
7. Unless needed as part of a wall in item 5a or 5b.
8. Except for any limitations on uninsulated glazed elements given in Table B5.
Provisions covering access and facilities for the fire service are to safeguard the health and safety of
people in and around the building. Their extent depends on the size and use of the building. Most
firefighting is carried out within the building. In the Secretary of State’s view, requirement B5 is met
by achieving all of the following.
a. External access enabling fire appliances to be used near the building.
b. Access into and within the building for firefighting personnel to both:
i. search for and rescue people
ii. fight fire.
c. Provision for internal fire facilities for firefighters to complete their tasks.
d. Ventilation of heat and smoke from a fire in a basement.
If an alternative approach is taken to providing the means of escape, outside the scope of this
approved document, additional provisions for firefighting access may be required. Where deviating
from the general guidance, it is advisable to seek advice from the fire and rescue service as early as
possible (even if there is no statutory duty to consult).
e. A facility to store building information for firefighters to complete their tasks.
Minimum fire resistance REI60 from both sides with E30 Sa fire doors
Minimum fire resistance REI 120 from accommodation side and REI60 from inside the shaft with E60 Sa fire doors
NOTES:
1.Outlets from a fire main should be located in the firefighting lobby or, in the case of a shaft serving flats, in the firefighting stairway (see Diagram b).
2.Smoke control should be provided in accordance with BS9999 or, where the firefighting shaft only serves flats, the provisions for smoke control given in paragraph 3.49 may be followed instead.
3.A firefighting lift is required if the building has a floor more than 18m above, or more than 10m below, fire service vehicle access level.
4.This diagram is only to illustrate the basic components and is not meant to represent the only acceptable layout. The firefighting shaft should be constructed generally in accordance with section 6 of BS 9999.
5.For the minimum fire resistance of lift doors see Table C1.
See paras 15.2,15.8 and 15.9
In general, doors on escape routes (whether or not the doors are fire doorsets) should be either of the following.
a. Not fitted with a lock, latch or bolt fastenings.
b. Fitted only with simple fastenings that are all of the following.
i. Easy to operate; it should be apparent how to undo the fastening.
ii. Operable from the side approached by people escaping.
iii. Operable without a key.
iv. Operable without requiring people to manipulate more than one mechanism.
Doors may be fitted with hardware to allow them to be locked when rooms are empty.
If a secure door is operated by code or combination keypad, swipe or proximity card, biometric data, etc., a security mechanism override should be possible from the side approached by people escaping.
Thermoplastic materials that do not meet the classifications in Table 4.1 can be used as described in paragraphs 4.13 to 4.17. No guidance for European fire test performance is currently available, because there is no generally accepted test and classification procedure.
Thermoplastic materials are defined in Appendix B, paragraph B11. Classifications used here are explained in paragraph B13.
Rooflights should meet the following classifications, according to material. No guidance for European fire test performance is currently available, because there is no generally accepted test and classification procedure.
a. Non-plastic rooflights should meet the relevant classification in Table 4.1.
b. Plastic rooflights, if the limitations in Table 4.2 and Table 12.2 are observed, should be a minimum class D-s3, d2 rating. Otherwise they should meet the relevant classification in Table 4.1.
Every joint, imperfect fit and opening for services through a fire-separating element should be sealed with fire-stopping to ensure that the fire resistance of the element is not impaired. Fire-stopping delays the spread of fire and, generally, the spread of smoke as well.
general access stair
The flights and landings of escape stairs should be constructed of materials achieving class A2-s3, d2 or better in all of the following situations.
a. If the escape stair is the only stair in a building with more than three storeys.
b. If the escape stair is within a basement storey.
c. If the escape stair serves any storey that has a floor level more than 18m above ground or access level.
d. If the escape stair is an external escape stair, except where the stair connects the ground storey or ground level with a floor or flat roof a maximum of 6m above or below ground level.
e. If the escape stair is a firefighting stair.
Materials achieving class B-s3, d2 or worse may be added to the top horizontal surface, except on firefighting stairs.
The flights and landings of escape stairs should be constructed of materials achieving class A2-s3, d2 or better in all of the following situations.
a. If the escape stair is the only stair in a building with more than three storeys.
b. If the escape stair is within a basement storey.
c. If the escape stair serves any storey that has a floor level more than 18m above ground or access level.
d. If the escape stair is an external escape stair, except where the stair connects the ground storey or ground level with a floor or flat roof a maximum of 6m above or below ground level.
e. If the escape stair is a firefighting stair.
Materials achieving class B-s3, d2 or worse may be added to the top horizontal surface, except on firefighting stairs.
Helical stairs and spiral stairs may form part of an escape route provided they are designed in accordance with BS 5395-2. If they are intended to serve members of the public, stairs should be type E (public) stairs.
Helical stairs and spiral stairs may form part of an escape route provided they are designed in accordance with BS 5395-2. If they are intended to serve members of the public, stairs should be type E (public) stairs.
ground floor
Height of top storey measured from upper floor surface of top floor to ground level on lowest side of building
Height of top storey excludes roof-top plant areas and any top storeys consisting exclusively of plant rooms
NOTES:
For single storey buildings, the periods under the heading ‘Up to 5’ apply. If single storey buildings have basements, for the basement storeys the period appropriate to their depth applies.
* For the floor over a basement or, if there is more than one basement, the floor over the topmost basement, the higher of the period for the basement storey and the period for the ground or upper storey applies.
† For compartment walls that separate buildings, the period is increased to a minimum of 60 minutes.
+ For any floor that does not contribute to the support of the building within a flat of more than one storey, the period is reduced to 30 minutes.
§ For flat conversions, refer to paragraphs 6.5 to 6.7 regarding the acceptability of 30 minutes.
‡ For elements that do not form part of the structural frame, the period is reduced to 90 minutes.
# For elements that protect the means of escape, the period is increased to 30 minutes.
1. Refer to note 1, Table B3 for the specific provisions of test.
2. Blocks of flats with a floor more than 30m above ground level should be fitted with a sprinkler system in accordance with Appendix E.
NOTE:
Sprinklers only need to be provided within the individual flats, they are not required in the common areas such as stairs, corridors or landings when these areas are fire sterile.
3.‘With sprinkler system’ means that the building is fitted throughout with an automatic sprinkler system in accordance with Appendix E.
4. Very large (over 18m in height or with a 10m deep basement) or unusual dwellinghouses are outside the scope of the guidance provided with regard to dwellinghouses.
5. A minimum of 30 minutes in the case of three storey dwellinghouses, increased to 60 minutes minimum for compartment walls separating buildings.
6. Buildings within the ‘office’, ‘shop and commercial’, ‘assembly and recreation’, ‘industrial’ and ‘storage and other non-residential’ (except car parks for light vehicles) purpose groups (purpose groups 3 to 7(a)) require sprinklers where there is a top storey above 30m.
The sprinkler system should be provided in accordance with Appendix E.
7. The car park should comply with the relevant provisions in the guidance on requirement B3, Section 11 of
Approved Document B Volume 2.
8. For the purposes of meeting the Building Regulations, the following types of steel elements are deemed to have satisfied the minimum period of fire resistance of 15 minutes when tested to the European test method.
i. Beams supporting concrete floors, maximum Hp/A=230m-1 operating under full design load.
ii. Free-standing columns, maximum Hp/A=180m-1 operating under full design load.
iii. Wind bracing and struts, maximum Hp/A=210m-1 operating under full design load.
Guidance is also available in BS EN 1993-1-2.
Volume 1 purpose groups
Purpose for which the building or compartment of a building is intended to be used
Residential(dwellings)
1(a)(1)Flat.
1(b)(2)Dwellinghouse that contains a habitable storey with a floor level a minimum of 4.5m above ground level up to a maximum of 18m.
(3)1(c)(2)(4)Dwellinghouse that does not contain a habitable storey with a floor level a minimum of 4.5m above ground level.
To assist the fire service to identify each floor in a block of flats with a top storey more than 11m above ground level (see Diagram D6), floor identification signs and flat indicator signs should be provided.
Air circulation systems which circulate air within an individual dwellinghouse with a floor more than
4.5m above ground level should meet the guidance given in paragraph 2.9.
guarding
A balcony or flat roof intended to form part of an escape route should be provided with guarding etc. in accordance with Approved Document K.
A balcony or flat roof intended to form part of an escape route should be provided with guarding etc. in accordance with Approved Document K.
Where a storey or part of a building has multiple escape routes available, one may be over a flat roof that complies with all of the following.
a. It should be part of the same building from which escape is being made.
b. The route across the roof should lead to a storey exit or external escape route.
c. The part of the roof (including its supporting structure) forming the escape route, and any opening within 3m of the escape route, should be of fire resisting construction (minimum REI 30).
d. The route should be clearly defined and guarded by walls and/or protective barriers to protect against falling.
Where a storey or part of a building has multiple escape routes available, one may be over a flat roof that complies with all of the following.
d. The route should be clearly defined and guarded by walls and/or protective barriers to protect against falling.
habitable room
A fire detection and alarm system should be installed where either of the
following applies.
a. A new habitable room is provided above or below the ground storey.
b. A new habitable room is provided at the ground storey, without a final exit.
A fire detection and alarm system should be installed where either of the
following applies.
a. A new habitable room is provided above or below the ground storey.
b. A new habitable room is provided at the ground storey, without a final exit.
Basement storeys containing habitable rooms should have one of the following.
a. An emergency escape window or external door providing escape from the basement (paragraph 2.10).
b. A protected stairway (paragraph 2.5a) leading from the basement to a final exit.
Basement storeys containing habitable rooms should have one of the following.
a. An emergency escape window or external door providing escape from the basement (paragraph 2.10).
b. A protected stairway (paragraph 2.5a) leading from the basement to a final exit.
All habitable rooms (excluding kitchens) should have either of the following.
a. An opening directly onto a hall leading to a final exit.
b. An emergency escape window or door, as described in paragraph 3.6.
All habitable rooms (excluding kitchens) should have either of the following.
a. An opening directly onto a hall leading to a final exit.
b. An emergency escape window or door, as described in paragraph 3.6.
All habitable rooms (excluding kitchens) should have either of the following.
a. An emergency escape window or external door, as described in paragraph 3.6.
b. In multi-storey flats, direct access to a protected internal stairway (minimum REI 30) leading to an exit from the flat.
All habitable rooms (excluding kitchens) should have either of the following.
a. An emergency escape window or external door, as described in paragraph 3.6.
b. In multi-storey flats, direct access to a protected internal stairway (minimum REI 30) leading to an exit from the flat.
One of the following approaches should be adopted, observing the inner room restrictions described in paragraphs 3.7 and 3.8.
a. Provide a protected entrance hall (minimum REI 30) serving all habitable rooms that meets the conditions shown in Diagram 3.2.
b. Plan the flat to meet the conditions shown in Diagram 3.3, so that both of the following apply.
i. The travel distance from the flat entrance door to any point in any habitable room is a maximum of 9m.
ii. Cooking facilities are remote from the main entrance door and do not impede the escape route from anywhere in the flat.
c. Provide an alternative exit from the flat complying with paragraph 3.19.
One of the following approaches should be adopted, observing the inner room restrictions described in paragraphs 3.7 and 3.8.
a. Provide a protected entrance hall (minimum REI 30) serving all habitable rooms that meets the conditions shown in Diagram 3.2.
b. Plan the flat to meet the conditions shown in Diagram 3.3, so that both of the following apply.
i. The travel distance from the flat entrance door to any point in any habitable room is a maximum of 9m.
ii. Cooking facilities are remote from the main entrance door and do not impede the escape route from anywhere in the flat.
c. Provide an alternative exit from the flat complying with paragraph 3.19.
Where access from any habitable room to the entrance hall or flat entrance is impossible without passing through another room, all of the following conditions should be met (Diagram 3.4).
a. Bedrooms should be separated from living accommodation by fire resisting construction (minimum REI 30) and fire doorsets (minimum E 20).
b. The alternative exit should be in the part of the flat that contains the bedrooms.
Where access from any habitable room to the entrance hall or flat entrance is impossible without passing through another room, all of the following conditions should be met (Diagram 3.4).
a. Bedrooms should be separated from living accommodation by fire resisting construction (minimum REI 30) and fire doorsets (minimum E 20).
b. The alternative exit should be in the part of the flat that contains the bedrooms.
When multi-storey flats do not have their own external entrance at ground level, adopt one of the following approaches.
a. Approach 1 – provide at least one alternative exit from each habitable room that is not on the entrance storey of the flat (Diagram 3.5 and paragraph 3.22).
b. Approach 2 – provide at least one alternative exit from each storey that is not the entrance storey of the flat. All habitable rooms should have direct access to a protected landing (Diagram 3.6 and paragraph 3.22).
Approach 3 – provide a protected stairway plus a sprinkler system in accordance with Appendix E (smoke alarms should also be provided in accordance with Section 1).
d. Approach 4 – if the vertical distance between the entrance storey of the flat and any of the storeys above or below does not exceed 7.5m, provide all of the following.
i. A protected stairway.
ii. Additional smoke alarms in all habitable rooms.
iii. A heat alarm in any kitchen.
When multi-storey flats do not have their own external entrance at ground level, adopt one of the following approaches.
a. Approach 1 – provide at least one alternative exit from each habitable room that is not on the entrance storey of the flat (Diagram 3.5 and paragraph 3.22).
b. Approach 2 – provide at least one alternative exit from each storey that is not the entrance storey of the flat. All habitable rooms should have direct access to a protected landing (Diagram 3.6 and paragraph 3.22).
Approach 3 – provide a protected stairway plus a sprinkler system in accordance with Appendix E (smoke alarms should also be provided in accordance with Section 1).
d. Approach 4 – if the vertical distance between the entrance storey of the flat and any of the storeys above or below does not exceed 7.5m, provide all of the following.
i. A protected stairway.
ii. Additional smoke alarms in all habitable rooms.
iii. A heat alarm in any kitchen.
Basement storeys containing habitable rooms should have one of the following.
a. An emergency escape window or external door providing escape from the basement (see paragraph 3.6).
b. A protected stairway (minimum REI 30) leading from the basement to a final exit.
Basement storeys containing habitable rooms should have one of the following.
a. An emergency escape window or external door providing escape from the basement (see paragraph 3.6).
b. A protected stairway (minimum REI 30) leading from the basement to a final exit.
handrail
A stair of acceptable width for everyday use will be sufficient for escape purposes. If it is also a firefighting stair, it should be at least 1100mm wide. The width is the clear width between the walls or balustrades. Any handrails and strings intruding into that width by a maximum of 100mm on each side may be ignored.
Width is measured according to the following.
a. For a door (or doorway), the clear width when the door is open (Diagram D1).
b. For an escape route, either of the following.
i. When the route is defined by walls: the width at 1500mm above finished floor level.
ii. Elsewhere: the minimum width of passage available between any fixed obstructions.
c. For a stair, the clear width between the walls or balustrades. On escape routes and stairs,
handrails and strings intruding into the width by a maximum of 100mm on each side may be
ignored. Rails used for guiding a stair-lift may be ignored, but it should be possible to park the
lift’s chair or carriage in a position that does not obstruct the stair or landing.
health & safety strategy
Lift machine rooms should be sited over the lift well where possible. Where buildings or part of a building with only one stairway make this arrangement impractical, the lift machine room should be sited outside the protected stairway.
hearth
In the Secretary of State’s view, requirement B3 is met by achieving all of the following.
a. For defined periods, loadbearing elements of structure withstand the effects of fire without
loss of stability.
b. Compartmentation of buildings by fire resisting construction elements.
c. Automatic fire suppression is provided where it is necessary.
d. Protection of openings in fire-separating elements to maintain continuity of the fire separation.
e. Inhibition of the unseen spread of fire and smoke in cavities, in order to reduce the risk of
structural failure and spread of fire and smoke, where they pose a threat to the safety of people
in and around the building.
The extent to which any of these measures are necessary is dependent on the use of the building
and, in some cases, its size, and on the location of the elements of construction.
The external envelope of a building should not contribute to undue fire spread from one part of a
building to another part. This intention can be met by constructing external walls so that both of
the following are satisfied.
a. The risk of ignition by an external source to the outside surface of the building and spread of
fire over the outside surface is restricted.
b. The materials used to construct external walls, and attachments to them, and how they are
assembled do not contribute to the rate of fire spread up the outside of the building.
The extent to which this is necessary depends on the height and use of the building.
Provisions covering access and facilities for the fire service are to safeguard the health and safety of
people in and around the building. Their extent depends on the size and use of the building. Most
firefighting is carried out within the building. In the Secretary of State’s view, requirement B5 is met
by achieving all of the following.
a. External access enabling fire appliances to be used near the building.
b. Access into and within the building for firefighting personnel to both:
i. search for and rescue people
ii. fight fire.
c. Provision for internal fire facilities for firefighters to complete their tasks.
d. Ventilation of heat and smoke from a fire in a basement.
If an alternative approach is taken to providing the means of escape, outside the scope of this
approved document, additional provisions for firefighting access may be required. Where deviating
from the general guidance, it is advisable to seek advice from the fire and rescue service as early as
possible (even if there is no statutory duty to consult).
e. A facility to store building information for firefighters to complete their tasks.
The external surfaces (i.e. outermost external material) of external walls should comply with the provisions in Table 10.1. The provisions in Table 10.1 apply to each wall individually in relation to its proximity to the relevant boundary.
NOTES:
None of the above designations are suitable for protected stairways.
Polycarbonate and uPVC rooflights that achieve a class C-s3, d2 rating by test (see paragraph 12.7) may be regarded as having a BROOF(t4) classification.
Where Diagram 5.2a or 5.2b applies, rooflights should be a minimum of 1500mm from the compartment wall.
If double-skinned or laminate products have upper and lower surfaces of different materials, the greater distance applies.
1. See also the guidance to requirement B2 in Section 4.
2. The designation of external roof surfaces is explained in Appendix B.
3. Single-skinned rooflight only, in the case of non-thermoplastic material.
4. The rooflight should also meet the provisions of Diagram 12.1.
NOTES:
1. Fire appliances are not standardised. The building control body may, in consultation with the local fire and rescue service, use other dimensions.
2. The road base can be designed to 12.5 tonne capacity. Structures such as bridges should have the full 17-tonne capacity. The weight of high reach appliances is distributed over a number of axles, so infrequent use of a route designed to accommodate 12.5 tonnes should not cause damage.
For the purposes of requirements B2 and B4, thermoplastic materials should be classified as TP(a)
rigid, TP(a) flexible or TP(b), as follows:
a. TP(a) rigid
i. rigid solid uPVC sheet
ii. solid (as distinct from double- or multi-skinned) polycarbonate sheet a minimum of 3mm
thick
iii. multi-skinned rigid sheet made from uPVC or polycarbonate that has a class 1 rating when
tested to BS 476-7
iv. any other rigid thermoplastic product, a specimen of which (at the thickness of the
product as put on the market), when tested to BS 2782-0 Method 508A, performs so that
both:
• the test flame extinguishes before the first mark
• the duration of flaming or afterglow does not exceed 5 seconds following removal of
the burner.
b. TP(a) flexible
Flexible products a maximum of 1mm thick that comply with the Type C requirements
of BS 5867-2 when tested to BS 5438 Test 2 with the flame applied to the surface of the
specimens for 5, 15, 20 and 30 seconds respectively, but excluding the cleansing procedure; and
c. TP(b)
i. rigid solid polycarbonate sheet products a maximum of 3mm thick, or multi-skinned
polycarbonate sheet products that do not qualify as TP(a) by test
ii. other products which, when a specimen of the material between 1.5 and 3mm thick is
tested in accordance with BS 2782-0 Method 508A, have a maximum rate of burning of
50mm/minute.
NOTE: If it is not possible to cut or machine a 3mm thick specimen from the product, then a 3mm
Any test evidence used to demonstrate the fire performance classification of a product or system should be carefully checked to ensure that it is applicable to the intended use. Small differences in detail, such as fixing method, joints, dimensions, the introduction of insulation materials and air gaps (ventilated or not), can significantly affect the performance.
heating and ventilation designer
The records should include details of all of the following. d. All passive fire safety measures, including all of the following. e. All of the following.
a. The fire safety strategy, including all assumptions in the design of the fire safety systems (such as fire load). Any risk assessments or risk analysis.
b. All assumptions in the design of the fire safety arrangements for the management of the building.
c. All of the following.
i. Escape routes (including occupant load and capacity of escape routes).
ii. Any provision to enable the evacuation of disabled people.
iii. Escape strategy (e.g. simultaneous or phased).
iv. Muster points.
i. Compartmentation (i.e. location of fire-separating elements).
ii. Cavity barriers.
iii. Fire doorsets, including fire doorsets fitted with a self-closing device and other doors equipped with relevant hardware (e.g. electronic security locks).
iv. Duct dampers.
v. Fire shutters.
i. Fire detector heads.
ii. Smoke detector heads.
iii. Alarm call points.
iv. Detection/alarm control boxes.
v. Alarm sounders.
vi. Emergency communications systems.
vii. CCTV.
viii. Fire safety signage.
ix. Emergency lighting.
x. Fire extinguishers.
xi. Dry or wet fire mains and other firefighting equipment.
xii. Other interior facilities for the fire and rescue service.
xiii. Emergency control rooms.
xiv. Location of hydrants outside the building.
xv. Other exterior facilities for the fire and rescue service.
f. All active fire safety measures, including both of the following.
i. Sprinkler system(s) design, including isolating valves and control equipment.
ii. Smoke control system(s) (or heating, ventilation and air conditioning system with a smoke control function) design, including mode of operation and control systems.
g. Any high risk areas (e.g. heating machinery) and particular hazards.
h. Plans of the building as built, showing the locations of the above.
i. Both of the following.
i. Specifications of any fire safety equipment provided, including all of the following.
• Operational details.
• Operators’ manuals.
• Software.
• System zoning.
• Routine inspection, testing and maintenance schedules.
ii. Records of any acceptance or commissioning tests.
j. Any other details appropriate for the specific building.
The records should include details of all of the following.
f. All active fire safety measures, including both of the following.
i. Sprinkler system(s) design, including isolating valves and control equipment.
ii. Smoke control system(s) (or heating, ventilation and air conditioning system with a smoke control function) design, including mode of operation and control systems.
height
Height of building
Height of top storey measured from upper floor surface of top floor to ground level on lowest side of building
Height of top storey excludes roof-top plant areas and any top storeys consisting exclusively of plant rooms
In buildings that include a ‘residential’ purpose (purpose groups 1 and 2) with a storey 11m or more in height (see Diagram D6 in Appendix D) balconies should meet either of the following conditions.
a. Only contain materials achieving class A1 or A2-s1, d0, except for any of the following.
i. Cavity trays when used between two leaves of masonry.
ii. Intumescent and fire-stopping materials where the inclusion of the materials is necessary to meet the requirements of Part B of Schedule 1 to the Building Regulations 2010.
iii. Membranes.
iv. Seals, gaskets, fixings, sealants and backer rods.
v. Thermal break materials where the inclusion of the materials is necessary to meet the thermal bridging requirements of Part L of Schedule 1 to the Building Regulations 2010.
vi. Any material achieving class A1fl or A2fl-s1 when it forms the top horizontal floor layer of a balcony and is provided with an imperforate substrate under it which extends to the full size of the class A1fl or A2fl-s1 material.
vii. Electrical installations.
viii. Fibre optic cables.
b. Achieve both of the following conditions.
Have an imperforate soffit which extends to the full area of the balcony, achieves a minimum REI 30 rating and is constructed of materials achieving class A2-s1, d0 or better.
ii. Materials achieving class B-s1, d0 or worse extending beyond the boundary of a single
compartment should include a band of material rated class A2-s1, d0 or better, a minimum of 300mm in width centred on that boundary line.
Where regulation 7(2) applies, that regulation prevails over all the provisions in this paragraph.
Regulation 7(1A) prohibits the use of relevant metal composite materials in the external walls of all buildings of any height.
In relation to buildings of any height or use, consideration should be given to the choice of materials (including their extent and arrangement) used for the external wall, or attachments to the wall (e.g. balconies, etc.), to reduce the risk of fire spread over the wall.
In a building with a storey 18m or more in height (see Diagram D6 in Appendix D) any insulation product, filler material (such as the core materials of metal composite panels, sandwich panels and window spandrel panels but not including gaskets, sealants and similar) etc. used in the construction of an external wall should be class A2-s3, d2 or better (see Appendix B). This restriction does not apply to masonry cavity wall construction which complies with Diagram 8.2 in Section 8. Where regulation 7(2) applies, that regulation prevails over all the provisions in this paragraph.
In buildings that include a ‘residential’ purpose (purpose groups 1 and 2) with a storey 11m or more in height (see Diagram D6 in Appendix D) any insulation product, filler material (such as the core materials of metal composite panels, sandwich panels and window spandrel panels but not including gaskets, sealants and similar) etc. used in the construction of an external wall should be class A2-s1, d0 or better (see Appendix B). This restriction does not apply to masonry cavity wall construction which complies with Diagram 8.2 in Section 8. Where regulation 7(2) applies, that regulation prevails over all the provisions in this paragraph.
Where escape from a dwellinghouse is to an enclosed space with exit only possible through other buildings (e.g. a courtyard or back garden), the length of the space should exceed whichever is the greater of the following.
a. The height of the dwellinghouse above ground level (x).
b. Where a rear extension is provided, the height of the extension (y).
See para 2.10
A lift shaft serving storeys above ground level should not serve any basement, if either of the following applies.
a. There is only one escape stair serving storeys above ground level and smoke from a basement fire would adversely affect escape routes in the upper storeys.
b. The lift shaft is within the enclosure to an escape stair that terminates at ground level.
No fire resistance required for door
1100mm zone above top landing
1100mm zone above top landing
6m maximum height of stair
Fire resisting window (minimum RE30)
1800mm zone of fire resisting construction at side of stair
Fire doorset (minimum E30)
Ground level or a roof or podium served by an independent stairway
6m maximum height of stair without weather protection
9m zone of fire resisting construction below stair
Ground level or a roof or podium served by an independent stairway
See para 3.68
A multi-storey flat with an independent external entrance at ground level is similar to a dwellinghouse and means of escape should be planned on the basis of Section 2, depending on the height of the top storey above ground level.
As an alternative to the provisions of paragraphs 5.12 to 5.14, the compartment wall may extend through the roof for a minimum of either of the following (see Diagram 5.2c).
a. Where the height difference between the two roofs is less than 375mm, 375mm above the top surface of the adjoining roof covering.
b. 200mm above the top surface of the adjoining roof covering where either of the following applies.
i. The height difference between the two roofs is 375mm or more.
ii. The roof coverings either side of the wall are of a material classified as BROOF(t4).
Compartment walls not described in paragraphs 7.8 and 7.9 should run the full height of the storey in which they are situated.
As an alternative to the provisions of paragraph 7.16 or 7.17, the compartment wall may extend through the roof for a minimum of either of the following (see Diagram 5.2c).
a. Where the height difference between the two roofs is less than 375mm, 375mm above the top surface of the adjoining roof covering.
b. 200mm above the top surface of the adjoining roof covering where either of the following applies.
i. The height difference between the two roofs is 375mm or more.
ii. The roof coverings either side of the wall are of a material classified as BROOF(t4).
Compartment walls forming a separated part of a building should run the full height of the building in a continuous vertical plane.
Separated parts can be assessed independently to determine the appropriate standard of fire resistance in each. The two separated parts can have different standards of fire resistance.
If the fire resisting construction of a protected escape route is either of the following.
a. Not carried to full storey height.
b. At the top storey, not carried to the underside of the roof covering.
Then the cavity above or below the fire resisting construction should be either of the following.
i. Fitted with cavity barriers on the line of the enclosure.
ii. For cavities above the fire resisting construction, enclosed on the lower side by a fire resisting ceiling (minimum EI 30) that extends throughout the building, compartment or separated part (see Diagram 8.3).
helical stair
Further guidance on the construction of firefighting stairs is given in Section 15 (see also paragraph 3.60). Dimensional constraints on the design of stairs are given in Approved Document K.
Helical stairs and spiral stairs may form part of an escape route provided they are designed in accordance with BS 5395-2. If they are intended to serve members of the public, stairs should be type E (public) stairs.
high-usage entrance door
Where there are multiple main uses that are not ancillary to one another (for example, shops with independent offices above), each use should be assigned to a purpose group in its own right.
Where there is doubt as to which purpose group is appropriate, the more onerous guidance should be applied.
Smoke alarms should be mains operated and conform to BS EN 14604.
Heat alarms should be mains operated and conform to BS 5446-2.
For flats, either of the following provisions should be made.
a. Provide access for a pumping appliance to within 45m of all points inside each flat of a block, measured along the route of the hose. Every elevation to which vehicle access is provided should have a suitable door(s), not less than 750mm wide, giving access to the interior of the building. Door(s) should be provided such that there is no more than 60m between each door and/or the end of that elevation (e.g. a 150m elevation would need at least two doors).
b. Provide fire mains in accordance with paragraphs 13.5 and 13.6.
Buildings with firefighting shafts should have fire mains provided in both of the following.
a. The firefighting stairs.
b. Where necessary, in protected stairways.
The criteria for providing firefighting shafts and fire mains are given in Section 15.
Blocks of flats (purpose group 1(a)) with a top storey more than 11m above ground level (see Diagram D6 in Appendix D) should be provided with a secure information box.
NOTE: Consideration should also be given to other buildings with large, complex or uncommon layouts where the provision of a secure information box may be beneficial.
Firefighting stairs and firefighting lifts should be approached from either of the following.
a. A firefighting lobby.
b. A protected corridor or protected lobby that complies with the following guidance.
i. Means of escape (Section 3).
ii. Compartmentation (Section 7).
Both the stair and lobby of the firefighting shaft should be provided with a means of venting smoke and heat (see clause 27.1 of BS 9999).
Only services associated with the firefighting shaft, such as ventilation systems and lighting for the firefighting shafts, should pass through or be contained within the firefighting shaft.
Doors of a firefighting lift landing should be a maximum of 7.5m from the door to the firefighting stair (Diagram 15.1).
Where a new storey is added through conversion to create a storey above 4.5m, both of the following should apply.
a. The full extent of the escape route should be addressed.
b. Fire resisting doors (minimum E 20) and partitions (minimum REI 30) should be provided, including upgrading the existing doors where necessary.
NOTE: Where the layout is open plan, new partitions should be provided to enclose the escape route (Diagram 2.2).
Where it is undesirable to replace existing doors because of historical or architectural merit, the possibility of retaining, and where necessary upgrading, them should be investigated.
One of the following approaches should be adopted, observing the inner room restrictions described in paragraphs 3.7 and 3.8.
a. Provide a protected entrance hall (minimum REI 30) serving all habitable rooms that meets the conditions shown in Diagram 3.2.
b. Plan the flat to meet the conditions shown in Diagram 3.3, so that both of the following apply.
i. The travel distance from the flat entrance door to any point in any habitable room is a maximum of 9m.
ii. Cooking facilities are remote from the main entrance door and do not impede the escape route from anywhere in the flat.
c. Provide an alternative exit from the flat complying with paragraph 3.19.
Where access from any habitable room to the entrance hall or flat entrance is impossible without passing through another room, all of the following conditions should be met (Diagram 3.4).
a. Bedrooms should be separated from living accommodation by fire resisting construction (minimum REI 30) and fire doorsets (minimum E 20).
b. The alternative exit should be in the part of the flat that contains the bedrooms.
When multi-storey flats do not have their own external entrance at ground level, adopt one of the following approaches.
a. Approach 1 – provide at least one alternative exit from each habitable room that is not on the entrance storey of the flat (Diagram 3.5 and paragraph 3.22).
b. Approach 2 – provide at least one alternative exit from each storey that is not the entrance storey of the flat. All habitable rooms should have direct access to a protected landing (Diagram 3.6 and paragraph 3.22).
Approach 3 – provide a protected stairway plus a sprinkler system in accordance with Appendix E (smoke alarms should also be provided in accordance with Section 1).
d. Approach 4 – if the vertical distance between the entrance storey of the flat and any of the storeys above or below does not exceed 7.5m, provide all of the following.
i. A protected stairway.
ii. Additional smoke alarms in all habitable rooms.
iii. A heat alarm in any kitchen.
Any alternative exit from a flat should comply with all of the following.
a. It should be remote from the main entrance door to the flat.
b. It should lead to a final exit, via a common stair if necessary, through one of the following.
i. A door to an access corridor, access lobby or common balcony.
ii. An internal private stair leading to an access corridor, access lobby or common balcony at another level.
iii. A door to a common stair.
iv. A door to an external stair.
v. A door to an escape route over a flat roof.
Any access route leading to a final exit or common stair should comply with the provisions for means of escape in the common parts of a flat (see paragraph 3.25).
The following paragraphs deal with means of escape from the entrance doors of
flats to a final exit. They do not apply to flats with a top storey that is a maximum
of 4.5m above ground level (designed in accordance with paragraphs 3.15 to 3.17).
Reference should also be made to the following.
a. Requirement B3 regarding compartment walls and protected shafts.
b. Requirement B5 regarding access for the fire and rescue service.
The following paragraphs deal with means of escape from the entrance doors of flats to a final exit.
A protected stairway should not be used for anything else, except a lift well or electricity meters.
Doors should be readily openable to avoid undue delay to people escaping. Doors on escape routes (both within and from the building) should comply with paragraphs 3.91 to 3.98. Guidance on door closing and ‘hold open’ devices for fire doorsets is set out in Appendix C.
NOTE: Paragraphs 3.91 to 3.98 do not apply to flat entrance doors.
In general, doors on escape routes (whether or not the doors are fire doorsets) should be either of the following.
a. Not fitted with a lock, latch or bolt fastenings.
b. Fitted only with simple fastenings that are all of the following.
i. Easy to operate; it should be apparent how to undo the fastening.
ii. Operable from the side approached by people escaping.
iii. Operable without a key.
iv. Operable without requiring people to manipulate more than one mechanism.
Doors may be fitted with hardware to allow them to be locked when rooms are empty.
If a secure door is operated by code or combination keypad, swipe or proximity card, biometric data, etc., a security mechanism override should be possible from the side approached by people escaping.
Electrically powered locks should return to the unlocked position in all of the following situations.
a. If the fire detection and alarm system operates.
b. If there is loss of power or system error.
c. If the security mechanism override is activated.
Security mechanism overrides for electrically powered locks should be a Type A call point, as described in BS 7273-4. The call point should be positioned on the side approached by people escaping. If the door provides escape in either direction, a call point should be installed on both sides of the door.
Any door opening towards a corridor or a stair should be recessed to prevent its swing encroaching on the effective width.
Doors should contain vision panels in both of the following situations.
a. Where doors on escape routes divide corridors.
b. Where doors are hung to swing both ways.
Approved Document M contains guidance about vision panels in doors across accessible corridors and Approved Document K contains guidance about the safety of glazing.
Where revolving doors, automatic doors and turnstiles are placed across escape routes they should comply with one of the following.
a. They are automatic doors of the required width and comply with one of the following conditions.
i. Their failsafe system provides outward opening from any open position.
ii. They have a monitored failsafe system to open the doors if the mains electricity supply fails.
iii. They failsafe to the open position if the power fails.
b. Non-automatic swing doors of the required width are provided immediately adjacent to the revolving or automatic door or turnstile.
The following fire doorsets are not required to comply with paragraph C11.
a. Doors to and within flats and dwellinghouses.
b. Bedroom doors in ‘residential (other)’ (purpose group 2(b)) premises.
c. Lift entrance/landing doors.
If a self-closing device would be considered to interfere with the normal approved use of the
building, self-closing fire doors may be held open by one of the following.
a. A fusible link, but not if the doorset is in an opening provided as a means of escape unless it
complies with paragraph C7.
b. An automatic release mechanism activated by an automatic fire detection and alarm system.
c. A door closer delay device.
hot water storage system package
An alternative source of water should be supplied where any of the following apply.
a. No piped water supply is available.
b. Pressure and flow in the water main are insufficient.
c. An alternative source of supply is proposed.
importer
In the Secretary of State’s view, requirement B2 is met by achieving a restricted spread of flame
over internal linings. The building fabric should make a limited contribution to fire growth,
including a low rate of heat release.
It is particularly important in circulation spaces, where linings may offer the main means by which
fire spreads and where rapid spread is most likely to prevent occupants from escaping.
Requirement B2 does not include guidance on the following.
a. Generation of smoke and fumes.
b. The upper surfaces of floors and stairs.
c. Furniture and fittings.
in use
External fire spread
B4.(1)The external walls of the building shall adequately resist the spread of fire over the walls and from one building to another, having regard to the height, use and position of the building.
(2)The roof of the building shall adequately resist the spread of fire over the roof and from one building to another, having regard to the use and position of the building.
Regulation 7 – Materials and workmanship
(1)Building work shall be carried out—
(a)with adequate and proper materials which—
(i)are appropriate for the circumstances in which they are used,
(ii)are adequately mixed or prepared, and
(iii)are applied, used or fixed so as adequately to perform the functions for which they are designed; and
(b)in a workmanlike manner.
(2)Subject to paragraph (3), building work shall be carried out so that materials which become part of an external wall, or specified attachment, of a relevant building are of European Classification A2-s1, d0 or A1, classified in accordance with BS EN 13501-1:2007+A1:2009 entitled “Fire classification of construction products and building elements. Classification using test data from reaction to fire tests” (ISBN 978 0 580 59861 6) published by the British Standards Institution on 30th March 2007 and amended in November 2009.
(3)Paragraph (2) does not apply to—
(a)cavity trays when used between two leaves of masonry;
(b)any part of a roof (other than any part of a roof which falls within paragraph (iv) of regulation 2(6))if that part is connected to an external wall;
(c)door frames and doors;
(d)electrical installations;
(e)insulation and water proofing materials used below ground level;
(f)intumescent and fire stopping materials where the inclusion of the materials is necessary to meet the requirements of Part B of Schedule 1;
(g)membranes;
(h)seals, gaskets, fixings, sealants and backer rods;
(i)thermal break materials where the inclusion of the materials is necessary to meet the thermal bridging requirements of Part L of Schedule 1; or
(j)window frames and glass.
(4)In this regulation—
(a)a “relevant building” means a building with a storey (not including roof-top plant areas or any storey consisting exclusively of plant rooms) at least 18 metres above ground level and which—
(i)contains one or more dwellings;
(ii)contains an institution; or
(iii)contains a room for residential purposes(excluding any room in a hostel, hotel or boarding house); and
(b)“above ground level” in relation to a storey means above ground level when measured from the lowest ground level adjoining the outside of a building to the top of the floor surface of the storey.
Fire safety information 38.
(1) This regulation applies where building work—
(a) consists of or includes the erection or extension of a relevant building; or
(b) is carried out in connection with a relevant change of use of a building, and Part B of Schedule 1 imposes a requirement in relation to the work.
(2) The person carrying out the work shall give fire safety information to the responsible person not later than the date of completion of the work, or the date of occupation of the building or extension, whichever is the earlier.
(3) In this regulation—
(a) “fire safety information” means information relating to the design and construction of the building or extension, and the services, fittings and equipment provided in or in connection with the building or extension which will assist the responsible person to operate and maintain the building or extension with reasonable safety;
(b) a “relevant building” is a building to which the Regulatory Reform (Fire Safety) Order 2005 applies, or will apply after the completion of building work;
(c) a “relevant change of use” is a material change of use where, after the change of use takes place, the Regulatory Reform (Fire Safety) Order 2005 will apply, or continue to apply, to the building; and
(d) “responsible person” has the meaning given by article 3 of the Regulatory Reform (Fire Safety) Order 2005.
Building uses are classified within different purpose groups, which represent different levels of hazard (see Table 0.1). A purpose group can apply to a whole building or a compartment within the building, and should relate to the main use of the building or compartment.
Where a building or compartment has more than one use, it is appropriate to assign each different use to its own purpose group in the following situations.
a. If the ancillary use is a flat.
b. If both of the following apply.
i. The building or compartment has an area of more than 280m2.
ii. The ancillary use relates to an area that is more than one-fifth of the total floor area of the building or compartment.
c. In ‘shop and commercial’ (purpose group 4) buildings or compartments, if the ancillary use is storage and both of the following apply.
i. The building or compartment has an area of more than 280m2.
ii. The storage area comprises more than one-third of the total floor area of the building or compartment.
Where a complex mix of uses exists, the effect that one use may have on another in terms of risk should be considered. It could be necessary to use guidance from both volumes, apply other guidance (such as from HTM 05-02 or Building Bulletin 100), and/or apply special measures to reduce the risk.
Regulations 5(k) and 6(3) provide that, where the use of a building is changed such that the building becomes a building described in regulation 7(4), the construction of the external walls, and specified attachments, must be investigated and, where necessary, work must be carried out to ensure they only contain materials achieving class A2-s1, d0 or class A1, other than those exempted by regulation 7(3).
NOTES:
The notional boundary should be set in the area between the two buildings using the following rules:
1. The notional boundary is assumed to exist in the space between the buildings and is positioned so that one of the buildings would comply with the provisions for space separation having regard to the amount of its unprotected area. In practice, if one of the buildings is existing, the position of the boundary will be set by the space separation factors for that building.
2. The siting of the new building, or the second building if both are new, can then be checked to see that it also complies, using the notional boundary as the relevant boundary for the second building.
Notional boundary
Site boundary
Compliance with the provisions for space separation in respect of building A
Compliance with the provisions for space separation in respect of building B
See para 11.5
NOTES:
1. Fire appliances are not standardised. The building control body may, in consultation with the local fire and rescue service, use other dimensions.
2. The road base can be designed to 12.5 tonne capacity. Structures such as bridges should have the full 17-tonne capacity. The weight of high reach appliances is distributed over a number of axles, so infrequent use of a route designed to accommodate 12.5 tonnes should not cause damage.
The external envelope of a building should not provide a medium for fire spread if it is likely to be a risk to health or safety. The use of combustible materials for cladding framework, or of combustible thermal insulation as an overcladding or in ventilated cavities, may present such a risk in tall buildings, even though the provisions for external surfaces in Diagram 40 may have been satisfied.
In a building with a storey 18m or more above ground level, insulation material used in ventilated cavities in the external wall construction should be of limited combustibility (see Appendix A). This restriction does not apply to masonry cavity wall construction which complies with Diagram 32 in Section 10. Advice on the use of thermal insulation material is given in the BRE Report Fire performance of external thermal insulation for walls of multi-storey buildings (BR 135, 1988).
Insulating core panels consist of an inner core of insulation sandwiched between, and bonded to, a membrane, such as galvanised steel or aluminium.
Where they are used internally they can present particular problems with regard to fire spread and should meet all of the following conditions.
a. Panels should be sealed to prevent exposure of the core to a fire. This includes at joints and where services penetrate the panel.
b. In high fire risk areas, such as kitchens, places of special fire hazard, or in proximity to where hot works occur, only class A1 cored panels should be used.
c. Fixing systems for all panels should be designed to take account of the potential for the panel to delaminate. For instance, where panels are used to form a suspended ceiling, the fixing should pass through the panel and support it from the lower face.
Thermoplastic materials that do not meet the classifications in Table 4.1 can be used as described in paragraphs 4.13 to 4.17. No guidance for European fire test performance is currently available, because there is no generally accepted test and classification procedure.
Thermoplastic materials are defined in Appendix B, paragraph B11. Classifications used here are explained in paragraph B13.
If air handling ducts pass through fire-separating elements, the fire performance of the elements should be maintained using one or more of the following four methods. In most ductwork systems, a combination of the four methods is best.
a. Method 1 – thermally activated fire dampers.
b. Method 2 – fire resisting enclosures.
c. Method 3 – protection using fire resisting ductwork.
d. Method 4 – automatically activated fire and smoke dampers triggered by smoke detectors.
Materials used for fire-stopping should be reinforced with (or supported by) materials rated class A2-s3, d2 or better to prevent displacement in both of the following cases.
a. Where the unsupported span is greater than 100mm.
b. Where non-rigid materials are used (unless subjected to appropriate fire resistance testing to show their suitability).
Where a proprietary sealing system is not used, fire-stop around the pipe, keeping the opening for the pipe as small as possible. The nominal internal diameter of the pipe should not exceed the relevant dimension given in Table 9.1. The diameter given in Table 9.1 for pipes of specification (b) used in situation 2 or 3 assumes that the pipes are part of an above-ground drainage system and are enclosed as shown in Diagram 9.1. If they are not, the smaller diameter given for situation 5 should be used.
This document uses the European classification system for reaction to fire set out in BS EN 13501-1;
however, there may be some products lawfully on the market using the classification system set
out in previous editions. Where this is the case, Table B1 can be used for the purposes of this
document.
NOTE: The national classifications do not automatically equate with the transposed classifications
in the ‘BS EN 13501-1 classification’ column, therefore products cannot typically assume a European
class unless they have been tested accordingly.
NOTE: A classification of s3, d2 indicates that no limit is set for production of smoke and/or
flaming droplets/particles. If a performance for production of smoke and/or flaming droplets/
particles is specified, then only the European classes can be used. For example, a national class may
not be used as an alternative to a classification which includes s1, d0.
This document uses the European classification system for roof covering set out in BS EN 13501-5; however, there may be some products lawfully on the market using the classification system set out in previous editions. Where this is the case, Table B2 can be used for the purposes of this document.
This document uses the European classification system for fire resistance set out in BS EN 13501-2 to 4; however, there may be some products lawfully on the market using the classification system set out in previous editions. In those situations the alternative classifications given in Table B3 can be used.
Where it is proposed to assess the classification of a product or system in lieu of carrying out a specific test (as in paragraph B1c), this should be done in accordance with the relevant standard for extended application for the test in question and should include details of the test evidence that has been used to support the assessment.
For performance classifications where there is no specific standard for extended
application, assessment reports should be produced in accordance with the principles of BS EN 15725 and should include details of the test evidence that has been used to support the assessment. Further information on best practice is provided in the Passive Fire Protection Forum’s Guide to Undertaking Technical Assessments of the Fire Performance of Construction Products Based on Fire Test Evidence.
NOTE: Regulation 7(2) limits components used in or on the external walls of certain buildings to materials achieving class A2-s1, d0 or class A1 (see Section 12).
Assessments cannot be used to demonstrate compliance with this requirement.
To reduce the testing burden on manufacturers, BS EN 13238 defines a number of standard substrates that produce test results representative of different end use applications. The classification for reaction to fire achieved during testing is only valid when the product is used within this field of application, i.e. when the product is fixed to a substrate of that class in its end use. The standard substrate selected for testing should take account of the intended end use applications (field of application) of the product and represent end use substrates that have a density of a minimum of 75 of the standard substrate's nominal density.
For the systems described in paragraph E5, both of the following apply if pumps are used to draw
water from two tanks.
a. Each pump should be able to draw water from either tank.
b. Any one pump, or either tank, should be able to be isolated.
The sprinkler water supplies should not be used as connections for other services or other fixed
firefighting systems.
information management
The aim of this regulation is to ensure that the person responsible for the building has sufficient
information relating to fire safety to enable them to manage the building effectively. The aim of
regulation 38 will be achieved when the person responsible for the building has all the information
to enable them to do all of the following.
a. Understand and implement the fire safety strategy of the building.
b. Maintain any fire safety system provided in the building.
c. Carry out an effective fire risk assessment of the building.
information manager
The aim of this regulation is to ensure that the person responsible for the building has sufficient
information relating to fire safety to enable them to manage the building effectively. The aim of
regulation 38 will be achieved when the person responsible for the building has all the information
to enable them to do all of the following.
a. Understand and implement the fire safety strategy of the building.
b. Maintain any fire safety system provided in the building.
c. Carry out an effective fire risk assessment of the building.
inner room
a. Surface area: roofs and rooflights In each case measure the visible area
b. Floor area: Room, garage, conservatory or outbuilding, measure to inner surface of enclosing walls
c. Floor area: Storey, part or compartment, measure to inner surface of enclosing walls and include internal walls and partitions
An inner room is permitted when it is one of the following.
a. A kitchen.
b. A laundry or utility room.
c. A dressing room.
d. A bathroom, WC or shower room.
e. Any room on a storey that is a maximum of 4.5m above ground level which is provided with an emergency escape window as described in paragraph 2.10.
f. A gallery that complies with paragraph 2.15.
A room accessed only via an inner room (an inner inner room) is acceptable when all of the following apply.
a. It complies with paragraph 2.11.
b. The access rooms each have a smoke alarm (see Section 1).
c. None of the access rooms is a kitchen.
One of the following approaches should be adopted, observing the inner room restrictions described in paragraphs 3.7 and 3.8.
a. Provide a protected entrance hall (minimum REI 30) serving all habitable rooms that meets the conditions shown in Diagram 3.2.
b. Plan the flat to meet the conditions shown in Diagram 3.3, so that both of the following apply.
i. The travel distance from the flat entrance door to any point in any habitable room is a maximum of 9m.
ii. Cooking facilities are remote from the main entrance door and do not impede the escape route from anywhere in the flat.
c. Provide an alternative exit from the flat complying with paragraph 3.19.
See para 3.19
NOTE: The bedrooms are not classified as inner rooms because escape is possible in two directions.
Fire doorset
Fire resisting construction (minimum REI 30) between living and bedroom accommodation
Alternative exit
An inner room is permitted when it is one of the following.
a. A kitchen.
b. A laundry or utility room.
c. A dressing room.
d. A bathroom, WC or shower room.
e. Any room on a storey that is a maximum of 4.5m above ground level which is provided with an emergency escape window as described in paragraph 3.6.
f. A gallery that complies with paragraph 3.13.
A room accessed only via an inner room (an inner inner room) is acceptable when all of the following apply.
a. It complies with paragraph 3.7.
b. The access rooms each have a smoke alarm (see Section 1).
c. None of the access rooms is a kitchen.
installation instructions
In addition to any other provisions in this section, both of the following conditions should be met.
a. Joints between fire-separating elements should be fire-stopped.
b. Openings through a fire resisting element for pipes, ducts, conduits or cable should be all of the following.
i. As few as possible.
ii. As small as practicable.
iii. Fire-stopped (allowing thermal movement in the case of a pipe or duct).
NOTE: The fire-stopping around fire dampers, fire resisting ducts, fire and smoke dampers and smoke control ducts should be in accordance with the manufacturer or supplier’s installation instructions.
instruction
In addition to any other provisions in this section, both of the following conditions should be met.
a. Joints between fire-separating elements should be fire-stopped.
b. Openings through a fire resisting element for pipes, ducts, conduits or cable should be all of the following.
i. As few as possible.
ii. As small as practicable.
iii. Fire-stopped (allowing thermal movement in the case of a pipe or duct).
NOTE: The fire-stopping around fire dampers, fire resisting ducts, fire and smoke dampers and smoke control ducts should be in accordance with the manufacturer or supplier’s installation instructions.
intermittent operation
Each flat in a block should have alarms as set out in paragraphs 1.1 to 1.4. With effective compartmentation, a communal fire alarm system is not normally needed. In some buildings, detectors in common parts of the building may need to operate smoke control or other fire protection systems but do not usually sound an audible warning.
Smoke alarms should be mains operated and conform to BS EN 14604.
A protected circuit to operate equipment during a fire should achieve all of the following.
a. Cables should achieve PH 30 classification when tested in accordance with BS EN 50200 (incorporating Annex E) or an equivalent standard.
b. It should only pass through parts of the building in which the fire risk is negligible.
c. It should be separate from any circuit provided for another purpose.
In general, doors on escape routes (whether or not the doors are fire doorsets) should be either of the following.
a. Not fitted with a lock, latch or bolt fastenings.
b. Fitted only with simple fastenings that are all of the following.
i. Easy to operate; it should be apparent how to undo the fastening.
ii. Operable from the side approached by people escaping.
iii. Operable without a key.
iv. Operable without requiring people to manipulate more than one mechanism.
Doors may be fitted with hardware to allow them to be locked when rooms are empty.
If a secure door is operated by code or combination keypad, swipe or proximity card, biometric data, etc., a security mechanism override should be possible from the side approached by people escaping.
Under fire conditions, ventilation and air-conditioning systems should be compatible with smoke control systems and need to be considered in their respective design.
The performance requirement is in terms of integrity (E) for a period of minutes. An additional
classification of Sa is used for all doors where restricted smoke leakage at ambient temperatures is
needed.
internal floor
Elements of structure such as structural frames, beams, columns, loadbearing walls (internal and external), floor structures and gallery structures should have, as a minimum, the fire resistance given in Appendix B, Table B3.
Elements of structure such as structural frames, beams, columns, loadbearing walls (internal and external), floor structures and gallery structures should have, as a minimum, the fire resistance given in Appendix B, Table B3.
NOTE: If one element of structure supports or stabilises another, as a minimum the supporting element should have the same fire resistance as the other element.
internal wall
Internal fire spread (linings)
B2.(1) To inhibit the spread of fire within the building, the internal linings shall —
(a) adequately resist the spread of flame over their surfaces; and
(b) have, if ignited, either a rate of heat release or a rate of fire growth, which is reasonable in the circumstances.
(2) In this paragraph “internal linings” means the materials or products used in lining any partition, wall, ceiling or other internal structure.
In every case measure the volume contained by all of the following.
a. Under surface of roof.
b. Upper surface of lowest floor.
c. Inner surface of enclosing walls.
When there is not an outer enclosingwall, measure to the outermost edge of the floor slab.
The measured volume should include internal walls and partitions.
a. Cubic capacity of a building Internal wall or partition
b. Cubic capacity of compartments or separated part of a building
Diagram D2 Cubic capacity
With some configurations of external wall, a fire in one part of a building could subject the external wall of a protected stairway to heat (for example, where the two are adjacent at an internal angle in the façade, as shown in Diagram 3.10).
If a protected stairway projects beyond, is recessed from or is in an internal angle of the adjoining external wall of the building, then the minimum distance between an unprotected area of the building enclosure and an unprotected area of the stair enclosure should be 1800mm.
Elements of structure such as structural frames, beams, columns, loadbearing walls (internal and external), floor structures and gallery structures should have, as a minimum, the fire resistance given in Appendix B, Table B3.
Cavity barriers should be provided at all of the following locations.
a. At the edges of cavities, including around openings (such as windows, doors and exit/entry points for services).
b. At the junction between an external cavity wall and every compartment floor and compartment wall.
c. At the junction between an internal cavity wall and every compartment floor, compartment wall or other wall or door assembly forming a fire resisting barrier.
This does not apply where a wall meets the conditions of Diagram 5.3.
Elements of structure such as structural frames, beams, columns, loadbearing walls (internal and external), floor structures and gallery structures should have, as a minimum, the fire resistance given in Appendix B, Table B3.
NOTE: If one element of structure supports or stabilises another, as a minimum the supporting element should have the same fire resistance as the other element.
Cavity barriers should be provided at all of the following locations.
a. At the edges of cavities, including around openings (such as windows, doors and exit/entry points for services).
b. At the junction between an external cavity wall and every compartment floor and compartment wall.
c. At the junction between an internal cavity wall and every compartment floor, compartment wall or other wall or door assembly forming a fire resisting barrier.
This does not apply where a wall meets the conditions of Diagram 8.2.
interstitial condensation
Relevant metal composite materials are defined (in regulation 2(6)(c)) as any panel or sheet, having a thickness of no more than 10mm which is composed of a number of layers two or more of which are made of metal, alloy or metal compound and one or more of which is a substantial layer made of a material having a gross calorific value of more than 35MJ/kg when tested in accordance with BS EN ISO 1716. A substantial layer is defined as a layer which is at least 1mm thick or has a mass per unit area of at least 1kg/m².
Standard substrates include gypsum plasterboard (BS EN 520) with a density of 700+/-100kg/m3,
calcium silicate board (BS EN 14306) 870+/-50kg/m3 and fibre-cement board 1800+/-200kg/m3.
NOTE: Standard calcium silicate board is not representative of gypsum plasterboard end use (due
to the paper layer), but would be representative of most gypsum plasters (with densities of more
than 650kg/m3).
NOTE: Classifications based on tests using a plasterboard substrate
introduction
Any test evidence used to demonstrate the fire performance classification of a product or system should be carefully checked to ensure that it is applicable to the intended use. Small differences in detail, such as fixing method, joints, dimensions, the introduction of insulation materials and air gaps (ventilated or not), can significantly affect the performance.
isolation
For the systems described in paragraph E5, both of the following apply if pumps are used to draw
water from two tanks.
a. Each pump should be able to draw water from either tank.
b. Any one pump, or either tank, should be able to be isolated.
The sprinkler water supplies should not be used as connections for other services or other fixed
firefighting systems.
junction
Cavity barriers should be provided at all of the following locations.
a. At the edges of cavities, including around openings (such as windows, doors and exit/entry points for services).
b. At the junction between an external cavity wall and every compartment floor and compartment wall.
c. At the junction between an internal cavity wall and every compartment floor, compartment wall or other wall or door assembly forming a fire resisting barrier.
This does not apply where a wall meets the conditions of Diagram 5.3.
a. ANY BUILDING OR COMPARTMENT
Roof covering over this distance to be designated BROOF(t4) rated on deck of material of class A2-s3, d2 or better. Roof covering and deck could be composite structure, e.g. profiled steel cladding.
Fire-stopping to be carried up to underside of roof covering, boarding or slab.
Roof covering to be designated BROOF(t4) rated for at least 1500mm either side of wall.
b. RESIDENTIAL (DWELLINGS) AND RESIDENTIAL (OTHER) A MAXIMUM OF 15M HIGH
Boarding (used as a substrate) or timber tiling battens may be carried over the wall provided that they are fully bedded in mortar (or other no less suitable material) where over the wall.
Thermoplastic insulation materials should not be carried over the wall.
Double-skinned insulated roof sheeting with a thermoplastic core should incorporate a band of material of class A2-s3, d2 at least 300mm wide centred over the wall.
Sarking felt may also be carried over the wall.
If roof support members pass through the wall, fire protection to these members for a distance of 1500mm on either side of the wall may be needed to delay distortion at the junction (see paragraph 5.9).
Double-skinned insulated roof sheeting should incorporate a band of material rated class A2-s3, d2 or better, a minimum of 300mm in width, centred over the wall.
If roof support members pass through the wall, fire protection to these members for a distance of 1500mm on either side of the wall may be needed to delay distortion at the junction (see paragraph 5.9).
Fire-stopping to be carried up to underside of roof covering, e.g. roof tiles.
Section X–X
Roof covering to be designated BROOF(t4) rated for at least this distance.
Roofing battens and sarking felt may be carried over the wall.
Fire-stopping to be carried up to underside of roof covering above and below sarking felt.
NOTES:
1. Fire-stopping should be carried over the full thickness of the wall.
2. Fire-stopping should be extended into any eaves.
3. The compartment wall does not necessarily need to be constructed of masonry.
c. ANY BUILDING OR COMPARTMENT
The wall should be extended up through the roof for a height of at least 375mm above the top surface of the adjoining roof covering.
Where there is a height difference of at least 375mm between two roofs or where the roof coverings on either side of the wall are BROOF(t4) rated, the height of the upstand/parapet wall above the highest roof may be reduced to 200mm.
See paras 5.12 to 5.15
Cavity barriers should be tightly fitted to a rigid construction and mechanically fixed in position. If this is not possible (e.g. where a cavity barrier joins to slates, tiles, corrugated sheeting or similar materials) the junction should be fire-stopped.
At the junction with another compartment wall or an external wall, the fire resistance of the compartmentation should be maintained. Fire-stopping that meets the provisions in paragraphs 9.24 to 9.29 should be provided.
At the junction of a compartment floor and an external wall with no fire resistance, the external wall should be restrained at floor level. The restraint should reduce movement of the wall away from the floor if exposed to fire.
Cavity barriers should be provided at all of the following locations.
a. At the edges of cavities, including around openings (such as windows, doors and exit/entry points for services).
b. At the junction between an external cavity wall and every compartment floor and compartment wall.
c. At the junction between an internal cavity wall and every compartment floor, compartment wall or other wall or door assembly forming a fire resisting barrier.
This does not apply where a wall meets the conditions of Diagram 8.2.
kitchen
All habitable rooms (excluding kitchens) should have either of the following.
a. An opening directly onto a hall leading to a final exit.
b. An emergency escape window or door, as described in paragraph 3.6.
All habitable rooms (excluding kitchens) should have either of the following.
a. An emergency escape window or external door, as described in paragraph 3.6.
b. In multi-storey flats, direct access to a protected internal stairway (minimum REI 30) leading to an exit from the flat.
See para 3.18
Flat entrance
Kitchen area
Bath
In mixed use buildings, non-domestic kitchens, car parks and plant rooms should have separate and independent extraction systems. Extracted air should not be recirculated.
Methods 1 and 4 should not be used for extract ductwork serving kitchens. The likely build-up of grease within the duct can adversely affect dampers.
ladder
The fire and rescue service should be able to manually open and close rolling shutters without the use of a ladder.
Fixed ladders should not be provided as a means of escape for members of the public. They should only be provided where a conventional stair is impractical, such as for access to plant rooms which are not normally occupied.
landing
Flats
1. Within the enclosures of a protected entrance hall or protected landing, or within fire resisting separation shown in Section 3, Diagram 3.4.
2. Within either:
a. the enclosures of a protected stairway
b. fire resisting separation shown in Diagram 2.2.
3. Within fire resisting separation either:
a. shown in Diagram 2.4
b. described in paragraph 2.16b.
4. Existing window between an attached/integral garage and the dwellinghouse.
5. Adjacent to an external escape stair (see paragraph 2.17 and Diagram 2.7) or roof escape route (see paragraph 2.13).
6. Between residential/sleeping accommodation and a common escape route (corridor, lobby or stair).
7. Between a protected stairway(1)and either:
a. the accommodation
b. a corridor that is not a protected corridor other than in item 6 above.
8. Between either:
a. a protected stairway(1)and a protected lobby or protected corridor
b. accommodation and a protected lobby other than in item 6 above.
9. Between the accommodation and a protected corridor that forms a dead end,other than in item 6 above.
10.Between accommodation and any other corridor, or sub-dividing corridors,other than in item 6 above.
11. Beside an external escape route.
Table B5
see Table B3
Table B5
12. Beside an external escape stair (see paragraph 3.68 and Diagram 3.11) or roof escape route (see paragraph 3.30).
NOTES:
Items 1 and 8 apply also to single storey buildings.
Fire resisting glass should be marked with the name of the manufacturer and the name of the product.
Further guidance can be found in A Guide to Best Practice in the Specification and Use of Fire-resistant Glazed Systems published by the Glass and Glazing Federation.
1. If the protected stairway is also a protected shaft or a firefighting stair (see Section 15), there may be further
restrictions on the use of glazed elements.
2. Measured vertically from the landing floor level or the stair pitch line.
3. The 100mm limit is intended to reduce the risk of fire spreading from a floor covering.
Any external escape stair should meet all of the following conditions (Diagram 2.7).
a. Doors to the stair should be fire resisting (minimum E 30), except for a single exit door from the building to the top landing of a downward-leading external stair.
b. Fire resisting construction (minimum RE 30) is required for the building envelope within the following zones, measured from the flights and landings of the external stair.
i. 1800mm horizontally.
ii. 9m vertically below.
iii. 1100mm above the top landing of the stair (except where the stair leads from basement to ground level).
c. Fire resisting construction (minimum RE 30) should be provided for any part of the building (including doors) within 1800mm of the escape route from the foot of the stair to a place of safety. This does not apply if there are alternative escape routes from the foot of the external escape stair.
d. Stairs more than 6m in height should be protected from adverse weather. Protection should prevent the build-up of snow or ice but does not require full enclosure.
e. Glazing in areas of fire resisting construction should be fixed shut and fire resisting (in terms of integrity, but not insulation) (minimum E 30).
Fire resisting window(minimum RE30)
No fire resistance required for door
1100mm zone above top landing
6m max. height without weather protection
1800mm zone of fire resisting construction at side of stairway
Fire doorset(minimum E30)
See para 2.17
No fire resistance required for door
1100mm zone above top landing
1100mm zone above top landing
6m maximum height of stair
Fire resisting window (minimum RE30)
1800mm zone of fire resisting construction at side of stair
Fire doorset (minimum E30)
Ground level or a roof or podium served by an independent stairway
6m maximum height of stair without weather protection
9m zone of fire resisting construction below stair
Ground level or a roof or podium served by an independent stairway
See para 3.68
Any external escape stair should meet all of the following conditions (Diagram 3.11).
a. Doors to the stair should be fire resisting (minimum E 30) and be fitted with a self-closing device, except for a single exit door from the building to the top landing of a downward-leading external stair, provided it is the only door onto the landing.
b. Fire resisting construction (minimum RE 30) is required for the building envelope within the following zones, measured from the flights and landings of the external stair.
i. 1800mm above and horizontally.
ii. 9m vertically below.
iii. 1100mm above the top landing of the stair (except where the stair leads from basement to ground level).
c. Fire resisting construction (minimum RE 30) should be provided for any part of the building (including doors) within 1800mm of the escape route from the foot of the stair to a place of safety. This does not apply if there are alternative escape routes from the foot of the external escape stair.
d. Glazing in areas of fire resisting construction should be fixed shut and fire resisting (in terms of integrity but not insulation) (minimum E 30).
e. Stairs more than 6m in height above ground level (e.g. where they are provided above a podium) should be protected from adverse weather. Protection should prevent the build-up of snow or ice but does not require full enclosure.
Blocks of flats with a top storey more than 11m above ground level (see Diagram D6) should be fitted with a sprinkler system throughout the building in accordance with Appendix E.
NOTE: Sprinklers should be provided within the individual flats, they do not need to be provided in the common areas such as stairs, corridors or landings when these areas are fire sterile.
The requirement is for test exposure from each side of the doorset separately. The exception is lift doors, which are tested from the landing side only.
leading edge (of door)
Doors should be readily openable to avoid undue delay to people escaping. Doors on escape routes (both within and from the building) should comply with paragraphs 3.91 to 3.98. Guidance on door closing and ‘hold open’ devices for fire doorsets is set out in Appendix C.
NOTE: Paragraphs 3.91 to 3.98 do not apply to flat entrance doors.
In general, doors on escape routes (whether or not the doors are fire doorsets) should be either of the following.
a. Not fitted with a lock, latch or bolt fastenings.
b. Fitted only with simple fastenings that are all of the following.
i. Easy to operate; it should be apparent how to undo the fastening.
ii. Operable from the side approached by people escaping.
iii. Operable without a key.
iv. Operable without requiring people to manipulate more than one mechanism.
Doors may be fitted with hardware to allow them to be locked when rooms are empty.
If a secure door is operated by code or combination keypad, swipe or proximity card, biometric data, etc., a security mechanism override should be possible from the side approached by people escaping.
Electrically powered locks should return to the unlocked position in all of the following situations.
a. If the fire detection and alarm system operates.
b. If there is loss of power or system error.
c. If the security mechanism override is activated.
Security mechanism overrides for electrically powered locks should be a Type A call point, as described in BS 7273-4. The call point should be positioned on the side approached by people escaping. If the door provides escape in either direction, a call point should be installed on both sides of the door.
Any door opening towards a corridor or a stair should be recessed to prevent its swing encroaching on the effective width.
Doors should contain vision panels in both of the following situations.
a. Where doors on escape routes divide corridors.
b. Where doors are hung to swing both ways.
Approved Document M contains guidance about vision panels in doors across accessible corridors and Approved Document K contains guidance about the safety of glazing.
Where revolving doors, automatic doors and turnstiles are placed across escape routes they should comply with one of the following.
a. They are automatic doors of the required width and comply with one of the following conditions.
i. Their failsafe system provides outward opening from any open position.
ii. They have a monitored failsafe system to open the doors if the mains electricity supply fails.
iii. They failsafe to the open position if the power fails.
b. Non-automatic swing doors of the required width are provided immediately adjacent to the revolving or automatic door or turnstile.
legislation
The Building Regulations do not impose any requirements on the management of a building, but do assume that it will be properly managed. This includes, for example, keeping protected escape routes virtually ‘fire sterile’.
Appropriate fire safety design considers the way in which a building will be managed. Any reliance on an unrealistic or unsustainable management regime cannot be considered to have met the requirements of the regulations.
Once the building is in use, the management regime should be maintained and a suitable risk assessment undertaken for any variation in that regime. Failure to take proper management responsibility may result in the prosecution of an employer, building owner or occupier under legislation such as the Regulatory Reform (Fire Safety) Order 2005.
Every doorway or other exit providing access to a means of escape, other than exits in ordinary use (e.g. main entrances), should be distinctively and conspicuously marked by an exit sign in accordance with BS ISO 3864-1 and BS 5499-4. For this reason, blocks of flats with a single stair in regular use would not usually require any fire exit signage.
Advice on fire safety signs, including emergency escape signs, is given in the HSE publication Safety Signs and Signals: Guidance on Regulations.
Some buildings may require additional signs to comply with other legislation.
level
Solar shading devices installed up to 4.5m above ground level are not required to meet the requirements of regulation 7(2).
See paras 2.1 to 2.6
Single storey dwellinghouse(see paragraph 2.1)
Dwellinghouse with one storey more than 4.5m above ground level(see paragraph 2.5)
Dwellinghouse with two or more storeys more than 4.5m above ground level(see paragraph 2.6)
See para 2.5
Alternative cavity barrier arrangements in roof space over protected stairway in a house with a storey more than 4.5m above ground level
Air circulation systems which circulate air within an individual dwellinghouse with a floor more than
4.5m above ground level should meet the guidance given in paragraph 2.9.
For flats more than 4.5m above ground level, a balcony outside an alternative exit should be a common balcony meeting the conditions described in paragraph 3.22.
See para 3.21
NOTE: This only applies where at least one storey is more than 4.5m above ground level.
Alternative exit
Bathroom
ENTRANCE LEVEL
LEVEL(S) ABOVE OR BELOW ENTRANCE LEVEL
level of detail
This section is a guide to the information that should be provided. Guidance is in terms of essential information and additional information for complex buildings; however, the level of detail required should be considered on a case-by-case basis.
level of information
Blocks of flats (purpose group 1(a)) with a top storey more than 11m above ground level (see Diagram D6 in Appendix D) should be provided with a secure information box.
NOTE: Consideration should also be given to other buildings with large, complex or uncommon layouts where the provision of a secure information box may be beneficial.
This section is a guide to the information that should be provided. Guidance is in terms of essential information and additional information for complex buildings; however, the level of detail required should be considered on a case-by-case basis.
life cycle of building
Height of building
Sprinkler systems installed in buildings can reduce the risk to life and significantly reduce the
degree of damage caused by fire within a building.
liftway
A lift well connecting different compartments should form a protected shaft (see Section 7).
Lift machine rooms should be sited over the lift well where possible. Where buildings or part of a building with only one stairway make this arrangement impractical, the lift machine room should be sited outside the protected stairway.
link 1
The performance of some doorsets set out in Table C1 is linked to the minimum periods of fire resistance for elements of structure given in Tables B3 and B4. Limitations on the use of uninsulated glazing in fire doorsets are given in Table B5.
If a self-closing device would be considered to interfere with the normal approved use of the
building, self-closing fire doors may be held open by one of the following.
a. A fusible link, but not if the doorset is in an opening provided as a means of escape unless it
complies with paragraph C7.
b. An automatic release mechanism activated by an automatic fire detection and alarm system.
c. A door closer delay device.
Two fire doorsets may be fitted in the same opening if each door is capable of closing the opening,
so the total fire resistance is the sum of their individual resistances. If the opening is provided as a
means of escape, both fire doorsets should be self-closing.
If one fire doorset is capable of being easily opened by hand and has a minimum of 30 minutes’ fire
resistance, the other fire doorset should comply with both of the following.
a. Be fitted with an automatic self-closing device.
b. Be held open by a fusible link.
Rolling shutters should be capable of manual opening and closing for firefighting purposes (see Section 15). Rolling shutters across a means of escape should only be released by a heat sensor, such as a fusible link or electric heat detector, in the immediate vicinity of the door. Unless a shutter is also intended to partially descend as part of a boundary to a smoke reservoir, shutters across a means of escape should not be closed by smoke detectors or a fire alarm system.
live/work unit
Paragraphs 3.6 to 3.23 deal with the means of escape within each flat. Paragraphs 3.25 to 3.89 deal with the means of escape in common areas of the building (including mixed use buildings in paragraphs 3.76 and 3.77). Guidance for live/work units is given in paragraph 3.24.
live–work units
If glazed elements in fire resisting enclosures and doors can only meet the required integrity performance, their use is limited. These limitations depend on whether the enclosure forms part of a protected shaft (see Section 7) and the provisions set out in Appendix B, Table B5. If both integrity and insulation performance can be met, there is no restriction in this document on the use or amount of glass.
localised obstruction
A stair of acceptable width for everyday use will be sufficient for escape purposes. If it is also a firefighting stair, it should be at least 1100mm wide. The width is the clear width between the walls or balustrades. Any handrails and strings intruding into that width by a maximum of 100mm on each side may be ignored.
NOTES:
1. Materials used to close the cavity in this arrangement do not need to achieve a specific performance in relation to fire resistance.
2. Domestic meter cupboards may be installed provided that the following conditions are met:
a. There are no more than two cupboards per dwelling
b. The openings in the outer wall leaf are not bigger than 800X500mm for each cupboard
c. The inner leaf is not penetrated except by a sleeve not more than 80X80mm, which is fire-stopped.
3. Materials achieving class B-s3, d2 or worse may be placed within the cavity.
See para 5.18
NOTES:
1. Materials used to close the cavity in this arrangement do not need to achieve a specific performance in relation to fire resistance.
2. Domestic meter cupboards may be installed provided that the following conditions are met:
a. There are no more than two cupboards per dwelling
b. The openings in the outer wall leaf are not bigger than 800X500mm for each cupboard
c. The inner leaf is not penetrated except by a sleeve not more than 80X80mm, which is fire-stopped.
3. Materials achieving class B-s3, d2 or worse may be placed within the cavity.
See para 8.3
Width is measured according to the following.
a. For a door (or doorway), the clear width when the door is open (Diagram D1).
b. For an escape route, either of the following.
i. When the route is defined by walls: the width at 1500mm above finished floor level.
ii. Elsewhere: the minimum width of passage available between any fixed obstructions.
c. For a stair, the clear width between the walls or balustrades. On escape routes and stairs,
handrails and strings intruding into the width by a maximum of 100mm on each side may be
ignored. Rails used for guiding a stair-lift may be ignored, but it should be possible to park the
lift’s chair or carriage in a position that does not obstruct the stair or landing.
maintenance provider
NOTES:
1.In assembly buildings (purpose group 5), a gallery is included as a storey, but not if it is a loading gallery, fly gallery, stage grid, lighting bridge, or any gallery provided for similar purposes, or for maintenance and repair.
2.In other purpose group buildings, galleries are not counted as a storey.
3.For the definition of basement, see Appendix A.
Details should be provided of all of the following.
a. Specifications of fire safety equipment provided, including routine maintenance schedules.
b. Any assumptions regarding the management of the building in the design of the fire safety arrangements.
c. Any provision enabling the evacuation of disabled people, which can be used when designing personal emergency evacuation plans.
Access to the fire damper and its actuating mechanism should be provided for inspection, testing and maintenance.
manager
The Building Regulations do not impose any requirements on the management of a building, but do assume that it will be properly managed. This includes, for example, keeping protected escape routes virtually ‘fire sterile’.
Appropriate fire safety design considers the way in which a building will be managed. Any reliance on an unrealistic or unsustainable management regime cannot be considered to have met the requirements of the regulations.
Once the building is in use, the management regime should be maintained and a suitable risk assessment undertaken for any variation in that regime. Failure to take proper management responsibility may result in the prosecution of an employer, building owner or occupier under legislation such as the Regulatory Reform (Fire Safety) Order 2005.
Details should be provided of all of the following.
a. Specifications of fire safety equipment provided, including routine maintenance schedules.
b. Any assumptions regarding the management of the building in the design of the fire safety arrangements.
c. Any provision enabling the evacuation of disabled people, which can be used when designing personal emergency evacuation plans.
The records should include details of all of the following.
b. All assumptions in the design of the fire safety arrangements for the management of the building.
manual control
Guidance on door closing and ‘hold open’ devices for fire doorsets is set out in Appendix C.
manual to the building regulations
Regulation 7(1)(a) requires that materials used in building work are appropriate for the circumstances in which they are used. Regulation 7(2) sets requirements in respect of external walls and specified attachments in relevant buildings.
NOTE: Further guidance on regulation 7(1) can be found in HM Government’s Manual to the Building Regulations.
manufacturer
In addition to any other provisions in this section, both of the following conditions should be met.
a. Joints between fire-separating elements should be fire-stopped.
b. Openings through a fire resisting element for pipes, ducts, conduits or cable should be all of the following.
i. As few as possible.
ii. As small as practicable.
iii. Fire-stopped (allowing thermal movement in the case of a pipe or duct).
NOTE: The fire-stopping around fire dampers, fire resisting ducts, fire and smoke dampers and smoke control ducts should be in accordance with the manufacturer or supplier’s installation instructions.
To reduce the testing burden on manufacturers, BS EN 13238 defines a number of standard substrates that produce test results representative of different end use applications. The classification for reaction to fire achieved during testing is only valid when the product is used within this field of application, i.e. when the product is fixed to a substrate of that class in its end use. The standard substrate selected for testing should take account of the intended end use applications (field of application) of the product and represent end use substrates that have a density of a minimum of 75 of the standard substrate's nominal density.
Recommendations for the specification, design, construction, installation and maintenance of fire
doorsets constructed with non-metallic door leaves are given in BS 8214.
Guidance on timber fire resisting doorsets, in relation to the new European test standard, may be
found in Timber Fire Resisting Doorsets: Maintaining Performance Under the New European Test
Standard published by the Timber Research and Development Association (TRADA).
Guidance for metal doors is given in Code of Practice for Fire Resisting Metal Doorsets published by
the Door and Shutter Manufacturers’ Association (DSMA).
mass per unit area
Relevant metal composite materials are defined (in regulation 2(6)(c)) as any panel or sheet, having a thickness of no more than 10mm which is composed of a number of layers two or more of which are made of metal, alloy or metal compound and one or more of which is a substantial layer made of a material having a gross calorific value of more than 35MJ/kg when tested in accordance with BS EN ISO 1716. A substantial layer is defined as a layer which is at least 1mm thick or has a mass per unit area of at least 1kg/m².
material changes of use
Fire safety information 38.
(1) This regulation applies where building work—
(a) consists of or includes the erection or extension of a relevant building; or
(b) is carried out in connection with a relevant change of use of a building, and Part B of Schedule 1 imposes a requirement in relation to the work.
(2) The person carrying out the work shall give fire safety information to the responsible person not later than the date of completion of the work, or the date of occupation of the building or extension, whichever is the earlier.
(3) In this regulation—
(a) “fire safety information” means information relating to the design and construction of the building or extension, and the services, fittings and equipment provided in or in connection with the building or extension which will assist the responsible person to operate and maintain the building or extension with reasonable safety;
(b) a “relevant building” is a building to which the Regulatory Reform (Fire Safety) Order 2005 applies, or will apply after the completion of building work;
(c) a “relevant change of use” is a material change of use where, after the change of use takes place, the Regulatory Reform (Fire Safety) Order 2005 will apply, or continue to apply, to the building; and
(d) “responsible person” has the meaning given by article 3 of the Regulatory Reform (Fire Safety) Order 2005.
Fire safety information 38.
(1) This regulation applies where building work—
(a) consists of or includes the erection or extension of a relevant building; or
(b) is carried out in connection with a relevant change of use of a building, and Part B of Schedule 1 imposes a requirement in relation to the work.
(2) The person carrying out the work shall give fire safety information to the responsible person not later than the date of completion of the work, or the date of occupation of the building or extension, whichever is the earlier.
(3) In this regulation—
(a) “fire safety information” means information relating to the design and construction of the building or extension, and the services, fittings and equipment provided in or in connection with the building or extension which will assist the responsible person to operate and maintain the building or extension with reasonable safety;
(b) a “relevant building” is a building to which the Regulatory Reform (Fire Safety) Order 2005 applies, or will apply after the completion of building work;
(c) a “relevant change of use” is a material change of use where, after the change of use takes place, the Regulatory Reform (Fire Safety) Order 2005 will apply, or continue to apply, to the building; and
(d) “responsible person” has the meaning given by article 3 of the Regulatory Reform (Fire Safety) Order 2005.
Regulations 5(k) and 6(3) provide that, where the use of a building is changed such that the building becomes a building described in regulation 7(4), the construction of the external walls, and specified attachments, must be investigated and, where necessary, work must be carried out to ensure they only contain materials achieving class A2-s1, d0 or class A1, other than those exempted by regulation 7(3).
Regulations 5(k) and 6(3) provide that, where the use of a building is changed such that the building becomes a building described in regulation 7(4), the construction of the external walls, and specified attachments, must be investigated and, where necessary, work must be carried out to ensure they only contain materials achieving class A2-s1, d0 or class A1, other than those exempted by regulation 7(3).
materials
Regulation 7(1A) prohibits the use of relevant metal composite materials in the external walls of all buildings of any height.
Area of fire resisting wall with materials more than 1mm thick and with a reaction to fire performance worse than class B-s3, d2 = a x b
Area of wall counted as unprotected area = 0.5a x b
Area of fire resisting wall with materials having a reaction to fire performance better than class B-s3, d2
See para 11.7
Where a fire resisting external wall has an external surface material that is worse than class B-s3, d2 and is more than 1mm thick, that part of the wall should be classified as an unprotected area equating to half its area (Diagram 11.4).
Table 12.3 sets the limitations for using thermoplastic materials with a TP(a) rigid or TP(b) (see also Diagram 12.1) classification. The method of classifying thermoplastic materials is given in Appendix B.
The highest National product performance classification for lining materials is Class O. This is achieved if a material or the surface of a composite product is either:
a. composed throughout of materials of limited combustibility; or
b. a Class 1 material which has a fire propagation index (I) of not more than 12 and sub-index (i1) of not more than 6.
Note: Class O is not a classification identified in any British Standard test.
The highest national product performance classification for lining materials is Class 0. This is achieved if a material or the surface of a composite product is either:
a. composed throughout of materials of limited combustibility; or
b. a Class 1 material which has a fire propagation index (I) of not more than 12 and sub-index (i1) of not more than 6.
Note: Class O is not a classification identified in any British Standard test.
Materials within this zone – at plane of ceiling – should comply with Table 4.1
Rooflights
See Table 4.2
Materials achieving class B-s3, d2 or worse used as a substrate to the roof covering and any timber tiling battens, fully bedded in mortar or other suitable material for the width of the wall (Diagram 5.2b), may extend over the compartment wall in buildings that are a maximum of 15m high.
Double-skinned insulated roof sheeting should incorporate a band of material rated class A2-s3, d2 or better, a minimum of 300mm in width, centred over the wall.
Double-skinned insulated roof sheeting with a thermoplastic core should incorporate a band of material rated class A2-s3, d2 or better, a minimum of 300mm in width, centred over the wall.
Other fire-stopping materials include the following. a. Cement mortar. b. Gypsum-based plaster. c. Cement-based or gypsum-based vermiculite/perlite mixes. d. Glass fibre, crushed rock, blast furnace slag or ceramic-based products (with or without resin binders). e. Intumescent mastics. These may be used in situations appropriate to the particular material. Not all materials will be suitable in every situation.
Thermoplastic material is any synthetic polymeric material that has a softening point below 200°C if tested to BS EN ISO 306 Method A120. Products formed from these materials cannot always be classified in the normal way. In those circumstances the following approach can be followed.
Thermoplastic materials used for window glazing, rooflights and lighting diffusers within suspended ceilings do not need to meet the criteria within paragraph B19 onwards, if the guidance to requirements B2 and B4 is followed.
A thermoplastic material alone when used as a lining to a wall or ceiling cannot be assumed to protect a substrate. The surface rating of both thermoplastic material and substrate must therefore meet the required classification. If, however, the thermoplastic material is fully bonded to a non-thermoplastic substrate, then only the surface rating of the composite needs to meet the required classification.
Unless shown to be satisfactory when tested as part of a fire doorset assembly, the essential components of any hinge on which a fire door is hung should be made entirely from materials that have a minimum melting point of 800°C.
means of escape
While many of the provisions in this approved document for means of escape from flats are applicable to sheltered housing, the nature of the occupancy may necessitate some additional fire protection measures. The extent of such measures will depend on the form of the development. For example, a group of specially adapted bungalows or two storey flats, with few communal facilities, will not need to be treated differently from other single storey or two storey dwellinghouses or flats.
In low rise buildings without deep basements, access for firefighting personnel is typically achieved by providing measures for fire service vehicle access in Section 13 and means of escape.
Where a flat roof forms part of a means of escape, it should comply with all of the following.
a. It should be part of the same building from which escape is being made.
b. The route across the roof should lead to a storey exit or external escape route.
c. The part of the roof (including its supporting structure) forming the escape route, and any opening within 3m of the escape route, should be of fire resisting construction (minimum REI 30).
Dwellinghouses with one internal stair should comply with paragraphs 2.5 and 2.6. In dwellinghouses with more than one stair, the stairs should provide effective alternative means of escape. The stairs should be physically separated by either of the following.
a. Fire resisting construction (minimum REI 30).
b. More than one room.
Separate guidance applies to means of escape within the flat and within the common parts of the building that lead to a place of safety. Flats at ground level are treated similarly to dwellinghouses. With increasing height, more complex provisions are needed.
Where a flat roof forms part of a means of escape, it should comply with all of the following.
a. It should be part of the same building from which escape is being made.
b. The route across the roof should lead to a storey exit or external escape route.
c. The part of the roof (including its supporting structure) forming the escape route, and any opening within 3m of the escape route, should be of fire resisting construction (minimum REI 30).
A multi-storey flat with an independent external entrance at ground level is similar to a dwellinghouse and means of escape should be planned on the basis of Section 2, depending on the height of the top storey above ground level.
The following paragraphs deal with means of escape from the entrance doors of
flats to a final exit. They do not apply to flats with a top storey that is a maximum
of 4.5m above ground level (designed in accordance with paragraphs 3.15 to 3.17).
Reference should also be made to the following.
a. Requirement B3 regarding compartment walls and protected shafts.
b. Requirement B5 regarding access for the fire and rescue service.
The following paragraphs deal with means of escape from the entrance doors of flats to a final exit.
Paragraphs 3.6 to 3.23 deal with the means of escape within each flat. Paragraphs 3.25 to 3.89 deal with the means of escape in common areas of the building (including mixed use buildings in paragraphs 3.76 and 3.77). Guidance for live/work units is given in paragraph 3.24.
Every doorway or other exit providing access to a means of escape, other than exits in ordinary use (e.g. main entrances), should be distinctively and conspicuously marked by an exit sign in accordance with BS ISO 3864-1 and BS 5499-4. For this reason, blocks of flats with a single stair in regular use would not usually require any fire exit signage.
Advice on fire safety signs, including emergency escape signs, is given in the HSE publication Safety Signs and Signals: Guidance on Regulations.
Some buildings may require additional signs to comply with other legislation.
In mixed use buildings, separate means of escape should be provided from any storeys or parts of storeys used for the ‘residential’ or ‘assembly and recreation’ purpose groups (purpose groups 1, 2 and 5), other than in the case of certain small buildings or buildings in which the residential accommodation is ancillary (see paragraphs 3.76 and 3.77)
In general, doors on escape routes (whether or not the doors are fire doorsets) should be either of the following.
a. Not fitted with a lock, latch or bolt fastenings.
b. Fitted only with simple fastenings that are all of the following.
i. Easy to operate; it should be apparent how to undo the fastening.
ii. Operable from the side approached by people escaping.
iii. Operable without a key.
iv. Operable without requiring people to manipulate more than one mechanism.
Doors may be fitted with hardware to allow them to be locked when rooms are empty.
If a secure door is operated by code or combination keypad, swipe or proximity card, biometric data, etc., a security mechanism override should be possible from the side approached by people escaping.
The door of any doorway or exit should be hung to open in the direction of escape whenever reasonably practicable. It should always be hung to open in the direction of escape if more than 60 people might be expected to use it during a fire.
In a converted building with a maximum of three storeys, a minimum REI 30 fire resistance could be accepted for elements of structure if the means of escape conform to the provisions of Section 3.
Rolling shutters should be capable of manual opening and closing for firefighting purposes (see Section 15). Rolling shutters across a means of escape should only be released by a heat sensor, such as a fusible link or electric heat detector, in the immediate vicinity of the door. Unless a shutter is also intended to partially descend as part of a boundary to a smoke reservoir, shutters across a means of escape should not be closed by smoke detectors or a fire alarm system.
measurement
In every case measure the volume contained by all of the following.
a. Under surface of roof.
b. Upper surface of lowest floor.
c. Inner surface of enclosing walls.
When there is not an outer enclosingwall, measure to the outermost edge of the floor slab.
The measured volume should include internal walls and partitions.
a. Cubic capacity of a building Internal wall or partition
b. Cubic capacity of compartments or separated part of a building
Diagram D2 Cubic capacity
a. Surface area: roofs and rooflights In each case measure the visible area
b. Floor area: Room, garage, conservatory or outbuilding, measure to inner surface of enclosing walls
c. Floor area: Storey, part or compartment, measure to inner surface of enclosing walls and include internal walls and partitions
Height of top storey measured from upper floor surface of top floor to ground level on lowest side of building
Height of top storey excludes roof-top plant areas and any top storeys consisting exclusively of plant rooms
Free area measured at right angles to air flow
Free area for louvred vent = a1+a2+a3+a4+a5
While many of the provisions in this approved document for means of escape from flats are applicable to sheltered housing, the nature of the occupancy may necessitate some additional fire protection measures. The extent of such measures will depend on the form of the development. For example, a group of specially adapted bungalows or two storey flats, with few communal facilities, will not need to be treated differently from other single storey or two storey dwellinghouses or flats.
The fire safety aspects of the Building Regulations aim to achieve reasonable standards of health and safety for people in and around buildings. People, regardless of ability, age or gender, should be able to access buildings and use their facilities. The fire safety measures incorporated into a building should take account of the needs of everyone who may access the building, both as visitors and as people who live or work in it. It is not appropriate, except in exceptional circumstances, to assume that certain groups of people will be excluded from a building because of its use. The provisions in this approved document are considered to be of a reasonable standard for most buildings. However, some people’s specific needs might not be addressed. In some situations, additional measures may be needed to accommodate these needs. This should be done on a case- by-case basis.
A large dwellinghouse of two storeys (excluding basement storeys) should be fitted with a Grade A
Category LD3 fire detection and alarm system, as described in BS 5839-6.
A large dwellinghouse of three or more storeys (excluding basement storeys) should be fitted with
a Grade A Category LD2 fire detection and alarm system as described in BS 5839-6.
In a building with a storey 18m or more in height (see Diagram D6 in Appendix D) any insulation product, filler material (such as the core materials of metal composite panels, sandwich panels and window spandrel panels but not including gaskets, sealants and similar) etc. used in the construction of an external wall should be class A2-s3, d2 or better (see Appendix B). This restriction does not apply to masonry cavity wall construction which complies with Diagram 8.2 in Section 8. Where regulation 7(2) applies, that regulation prevails over all the provisions in this paragraph.
In buildings that include a ‘residential’ purpose (purpose groups 1 and 2) with a storey 11m or more in height (see Diagram D6 in Appendix D) any insulation product, filler material (such as the core materials of metal composite panels, sandwich panels and window spandrel panels but not including gaskets, sealants and similar) etc. used in the construction of an external wall should be class A2-s1, d0 or better (see Appendix B). This restriction does not apply to masonry cavity wall construction which complies with Diagram 8.2 in Section 8. Where regulation 7(2) applies, that regulation prevails over all the provisions in this paragraph.
Parts of an external wall with less fire resistance than the appropriate amount given in Appendix B, Table B4, are called unprotected areas.
In a building with a storey 18m or more above ground level any insulation product, filler material (not including gaskets, sealants and similar) etc. used in the external wall construction should be of limited combustibility (see Appendix A). This restriction does not apply to masonry cavity wall construction
Fire service vehicle access to fire mains should be provided as described in paragraphs 13.5 and 13.6.
In low rise buildings without deep basements, access for firefighting personnel is typically achieved by providing measures for fire service vehicle access in Section 13 and means of escape.
Firefighting shafts and protected stairways should be positioned such that every part of each storey more than 18m above the fire and rescue service vehicle access level complies with the maximum distances given in paragraph 15.7. Distances should be measured from the fire main outlet on a route suitable for laying a hose.
NOTE: If the internal layout is not known, the distance should be measured at two-thirds of the direct distance.
Fire resistance test criteria are set out in Appendix C. Standards of performance are summarised in Table C1.
Thermoplastic materials that do not meet the classifications in Table 4.1 can be used as described in paragraphs 4.13 to 4.17. No guidance for European fire test performance is currently available, because there is no generally accepted test and classification procedure.
Thermoplastic materials are defined in Appendix B, paragraph B11. Classifications used here are explained in paragraph B13.
Any flexible membrane covering a structure, other than an air-supported structure, should comply with Appendix A of BS 7157.
In a converted building with four or more storeys, the full standard of fire resistance given in Appendix B is necessary.
Compartment walls not described in paragraphs 7.8 and 7.9 should run the full height of the storey in which they are situated.
Guidance on the design, installation and maintenance of measures to contain fires or slow their spread is given in Ensuring Best Practice for Passive Fire Protection in Buildings produced by the Association for Specialist Fire Protection (ASFP).
Performance of the resistance of roofs to external fire exposure is measured in terms of penetration through the roof construction and the spread of flame over its surface.
The number of occupants of a room, storey, building or part of a building is either of the following.
a. The maximum number of people it is designed to hold.
b. In buildings other than dwellings, the number of people calculated by dividing the area of
a room or storey(s) (m2) by a floor space factor (m2 per person) such as given in Table D1 for
guidance.
The free area of a smoke ventilator should be measured by either of the following.
a. The declared aerodynamic free area in accordance with BS EN 12101-2.
b. The total unobstructed cross-sectional area (geometric free area), measured in the plane where
the area is at a minimum and at right angles to the direction of air flow (Diagram D7).
multiple levels
Where multiple escape stairs serve the upper storeys, only one needs to end at ground level. Other stairs may connect with the basement storeys if there is a protected lobby or a protected corridor between the stairs and accommodation at each basement level.
no level applicable
Work should comply with Parts K and L of Schedule 1 to the Building Regulations. When complete, the building should comply with other applicable parts of Schedule 1 to at least the same level as before.
non-combustible material
Non-combustible materials are defined a. (National classes) when tested to BS 476: b. (European classes) when classified as class Table A6 identifies non-combustible products
in Table A6 either as listed products, or in terms
of performance:
Part 4:1970 Non-combustibility test for
materials or Part 11 :1982; or
A 1 in accordance with BS EN 13501-1 :2002
Fire classification of construction products
and building elements. Classification using
data from reaction to fire tests when tested
to BS EN ISO 1182:2002 Reaction to fire tests
for building products - Non-combustibility
test and BS EN ISO 1716:2002 Reaction to
fire tests for building products. Determination
of the gross calorific value.
and materials, and lists circumstances where
their use is necessary.
non-core service disciplines
A secure information box provides a secure facility to store information about a building for use by the fire service during an incident.
The performance requirement is in terms of integrity (E) for a period of minutes. An additional
classification of Sa is used for all doors where restricted smoke leakage at ambient temperatures is
needed.
non-self-resetting energy cut-out
Heat alarms should be mains operated and conform to BS 5446-2.
The air extraction system should comply with all of the following.
a. It should give at least 10 air changes per hour.
b. It should be capable of handling gas temperatures of 300°C for not less than one hour.
c. It should do either of the following.
i. Be activated automatically if the sprinkler system activates.
ii. Be activated by an automatic fire detection system that conforms to BS 5839-1 (minimum L3 standard).
Further information on equipment for removing hot smoke is given in BS EN 12101-3.
A gallery should comply with one of the following.
a. It should be provided with an alternative exit.
b. It should be provided with an emergency escape window, as described in paragraph 2.10, where the gallery floor is a maximum of 4.5m above ground level.
c. It should meet all the conditions shown in Diagram 2.6.
Where it is undesirable to replace existing doors because of historical or architectural merit, the possibility of retaining, and where necessary upgrading, them should be investigated.
All of the following precautions should be taken to avoid the spread of smoke and fire to the protected stairway.
a. Transfer grilles should not be fitted in any wall, door, floor or ceiling of the stair enclosure.
b. Any duct passing through the stair enclosure should be rigid steel. Joints between the ductwork and stair enclosure should be fire-stopped.
c. Ventilation ducts supplying or extracting air directly to or from a protected stairway should not serve other areas as well.
d. Any system of mechanical ventilation which recirculates air and which serves both the stair and other areas should be designed to shut down on the detection of smoke within the system.
e. For ducted warm air heating systems, a room thermostat should be sited in the living room. It should be mounted at a height between 1370mm and 1830mm above the floor. The maximum setting should be 27°C.
NOTE: Ventilation ducts passing through compartment walls should comply with the guidance in Section 9.
A gallery should comply with one of the following.
a. It should be provided with an alternative exit.
b. It should be provided with an emergency escape window, as described in paragraph 3.6, where the gallery floor is a maximum of 4.5m above ground level.
c. It should meet the conditions shown in Diagram 3.1.
For systems circulating air only within an individual flat, take all of the following precautions.
a. Transfer grilles should not be fitted in any wall, door, floor or ceiling of the enclosure.
b. Any duct passing through the enclosure should be rigid steel. Joints between the ductwork and enclosure should be fire-stopped.
c. Ventilation ducts serving the enclosure should not serve any other areas.
d. Any system of mechanical ventilation which recirculates air and which serves both the stair and other areas should be designed to shut down on the detection of smoke within the system.
e. For ducted warm air heating systems, a room thermostat should be sited in the living room. It should be mounted at a height between 1370mm and 1830mm above the floor. The maximum setting should be 27°C.
NOTE: Ventilation ducts passing through compartment walls should comply with the guidance in Section 9.
Escape route travel distances should comply with Table 3.1.
Escape routes should have a minimum clear headroom of 2m. The only projections allowed below this height are door frames.
To limit potential damage to cables in protected circuits, all of the following should apply.
a. Cables should be sufficiently robust.
b. Cable routes should be carefully selected and/or physically protected in areas where cables may be exposed to damage.
c. Methods of cable support should be class A1 rated and offer at least the same integrity as the cable. They should maintain circuit integrity and hold cables in place when exposed to fire.
Despite the provisions described, it is probable that some smoke will get into the common corridor or lobby from a fire in a flat.
There should therefore be some means of ventilating the common corridors/lobbies to control smoke and so protect the common stairs. This means of ventilation offers additional protection to that provided by the fire doors to the stair, as well as some protection to the corridors/lobbies.
Ventilation can be natural (paragraphs 3.50 to 3.53) or mechanical (paragraph 3.54).
A protected stairway should not be used for anything else, except a lift well or electricity meters.
Every protected stairway should lead to a final exit, either directly or via a protected exit passageway. Any protected exit corridor or stair should have the same standard of fire resistance and lobby protection as the stair it serves.
To reduce the potential for fire spread, cavity barriers should be provided for both of the following.
a. To divide cavities.
b. To close the edges of cavities.
Cavity barriers should not be confused with fire-stopping details (Section 9).
Cavity barriers should be tightly fitted to a rigid construction and mechanically fixed in position. If this is not possible (e.g. where a cavity barrier joins to slates, tiles, corrugated sheeting or similar materials) the junction should be fire-stopped.
NOTES:
1. Any metal (such as cast iron, copper or steel) which, if exposed to a temperature of 800°C, will not soften or fracture to the extent that flame or hot gas will pass through the wall of the pipe.
2. uPVC pipes that comply with either BS 4514 or BS 5255.
3. These diameters are only in relation to pipes that form part of an above-ground drainage system and are enclosed as shown in Diagram 9.1. In other cases, the maximum diameters given for situation 5 apply.
In mixed use buildings, non-domestic kitchens, car parks and plant rooms should have separate and independent extraction systems. Extracted air should not be recirculated.
Where ducts pass between fire-separating elements to serve multiple flats or dwellings, fire dampers or fire and smoke dampers should be actuated by both of the following.
a. Smoke detector-controlled automatic release mechanisms.
b. Thermally actuated devices.
Method 1 should not be used for extract ductwork passing through the enclosures of protected escape routes (Diagrams 9.3 and 9.4), as large volumes of smoke can pass thermal devices without triggering them.
Access to the fire damper and its actuating mechanism should be provided for inspection, testing and maintenance.
A pipe with a maximum nominal internal diameter of 160mm may be used with a sleeve made out of a high melting point metal, as shown in Diagram 9.2, if the pipe is made of one of the following.
a. Lead.
b. Aluminium.
c. Aluminium alloy.
d. Fibre-cement.
e. uPVC (pipes should also comply with either BS 4514 or BS 5255).
A high melting point metal means any metal (such as cast iron, copper or steel) which, if exposed to a temperature of 800°C, will not soften or fracture to the extent that flame or hot gas will pass through the wall of the pipe.
Ventilation ducts supplying or extracting air directly to or from a protected stairway should not also serve other areas. A separate ventilation system should be provided for each protected stairway.
Rolling shutters should be capable of manual opening and closing for firefighting purposes (see Section 15). Rolling shutters across a means of escape should only be released by a heat sensor, such as a fusible link or electric heat detector, in the immediate vicinity of the door. Unless a shutter is also intended to partially descend as part of a boundary to a smoke reservoir, shutters across a means of escape should not be closed by smoke detectors or a fire alarm system.
nosing
Helical stairs and spiral stairs may form part of an escape route provided they are designed in accordance with BS 5395-2. If they are intended to serve members of the public, stairs should be type E (public) stairs.
notified body
BS EN 13501-5
BS 476-3
NOTE:
The national classifications do not automatically equate with the transposed classifications
in the European column, therefore products cannot typically assume a European class unless they
have been tested accordingly.
NOTES:
1. Fire appliances are not standardised. The building control body may, in consultation with the local fire and rescue service, use other dimensions.
2. The road base can be designed to 12.5 tonne capacity. Structures such as bridges should have the full 17-tonne capacity. The weight of high reach appliances is distributed over a number of axles, so infrequent use of a route designed to accommodate 12.5 tonnes should not cause damage.
Gas service and installation pipes and meters should not be within a protected stairway, unless installed in accordance with the Pipelines Safety Regulations 1996 and the Gas Safety (Installation and Use) Regulations 1998.
In a protected shaft, any pipe carrying natural gas or LPG should be both of the following.
a. Of screwed steel or all-welded steel construction.
b. Installed in accordance with both of the following.
i. The Pipelines Safety Regulations 1996.
ii. The Gas Safety (Installation and Use) Regulations 1998.
Tests and assessments should be carried out by organisations with the necessary expertise. For NOTE: Standard fire tests do not directly measure fire hazard. They measure or assess the response
example, organisations listed as ‘notified bodies’ in accordance with the European Construction Products Regulation or laboratories accredited by the United Kingdom Accreditation Service (UKAS)
for the relevant test standard can be assumed to have the necessary expertise.
of a material or system to exposure to one or more aspects of fire conditions. Performance in fire
tests is only one of a number of factors that should be taken into account.
notional boundary
NOTES:
The notional boundary should be set in the area between the two buildings using the following rules:
1. The notional boundary is assumed to exist in the space between the buildings and is positioned so that one of the buildings would comply with the provisions for space separation having regard to the amount of its unprotected area. In practice, if one of the buildings is existing, the position of the boundary will be set by the space separation factors for that building.
2. The siting of the new building, or the second building if both are new, can then be checked to see that it also complies, using the notional boundary as the relevant boundary for the second building.
Notional boundary
Site boundary
Compliance with the provisions for space separation in respect of building A
Compliance with the provisions for space separation in respect of building B
See para 11.5
The boundary that a wall faces is the relevant boundary (Diagram 11.2). It may be one of the following.
a. The site boundary.
b. The centre line of a space where further development is unlikely, such as a road, railway, canal or river.
c. An assumed notional boundary between two buildings on the same site (Diagram 11.3) where either of the following conditions is met.
i. One or both of the buildings are in the "residential" or "assembly and recreation" purpose groups (purpose group 1, 2 or 5).
ii. The buildings will be operated/managed by different organisations.
occupiable room
Fixed ladders should not be provided as a means of escape for members of the public. They should only be provided where a conventional stair is impractical, such as for access to plant rooms which are not normally occupied.
octave band
If glazed elements in fire resisting enclosures and doors can only meet the required integrity performance, their use is limited. These limitations depend on whether the enclosure forms part of a protected shaft (see Section 7) and the provisions set out in Appendix B, Table B5. If both integrity and insulation performance can be met, there is no restriction in this document on the use or amount of glass.
operation
Smoke alarms should be mains operated and conform to BS EN 14604.
Heat alarms should be mains operated and conform to BS 5446-2.
operational manual
The records should include details of all of the following. d. All passive fire safety measures, including all of the following. e. All of the following.
a. The fire safety strategy, including all assumptions in the design of the fire safety systems (such as fire load). Any risk assessments or risk analysis.
b. All assumptions in the design of the fire safety arrangements for the management of the building.
c. All of the following.
i. Escape routes (including occupant load and capacity of escape routes).
ii. Any provision to enable the evacuation of disabled people.
iii. Escape strategy (e.g. simultaneous or phased).
iv. Muster points.
i. Compartmentation (i.e. location of fire-separating elements).
ii. Cavity barriers.
iii. Fire doorsets, including fire doorsets fitted with a self-closing device and other doors equipped with relevant hardware (e.g. electronic security locks).
iv. Duct dampers.
v. Fire shutters.
i. Fire detector heads.
ii. Smoke detector heads.
iii. Alarm call points.
iv. Detection/alarm control boxes.
v. Alarm sounders.
vi. Emergency communications systems.
vii. CCTV.
viii. Fire safety signage.
ix. Emergency lighting.
x. Fire extinguishers.
xi. Dry or wet fire mains and other firefighting equipment.
xii. Other interior facilities for the fire and rescue service.
xiii. Emergency control rooms.
xiv. Location of hydrants outside the building.
xv. Other exterior facilities for the fire and rescue service.
f. All active fire safety measures, including both of the following.
i. Sprinkler system(s) design, including isolating valves and control equipment.
ii. Smoke control system(s) (or heating, ventilation and air conditioning system with a smoke control function) design, including mode of operation and control systems.
g. Any high risk areas (e.g. heating machinery) and particular hazards.
h. Plans of the building as built, showing the locations of the above.
i. Both of the following.
i. Specifications of any fire safety equipment provided, including all of the following.
• Operational details.
• Operators’ manuals.
• Software.
• System zoning.
• Routine inspection, testing and maintenance schedules.
ii. Records of any acceptance or commissioning tests.
j. Any other details appropriate for the specific building.
The records should include details of all of the following.
i. Both of the following.
i. Specifications of any fire safety equipment provided, including all of the following.
• Operational details.
• Operators’ manuals.
• Software.
• System zoning.
• Routine inspection, testing and maintenance schedules.
ii. Records of any acceptance or commissioning tests.
The records should include details of all of the following.
i. Both of the following.
i. Specifications of any fire safety equipment provided, including all of the following.
• Operational details.
• Operators’ manuals.
• Software.
• System zoning.
• Routine inspection, testing and maintenance schedules.
part b - fire safety
Any external escape stair should meet all of the following conditions (Diagram 2.7).
a. Doors to the stair should be fire resisting (minimum E 30), except for a single exit door from the building to the top landing of a downward-leading external stair.
b. Fire resisting construction (minimum RE 30) is required for the building envelope within the following zones, measured from the flights and landings of the external stair.
i. 1800mm horizontally.
ii. 9m vertically below.
iii. 1100mm above the top landing of the stair (except where the stair leads from basement to ground level).
c. Fire resisting construction (minimum RE 30) should be provided for any part of the building (including doors) within 1800mm of the escape route from the foot of the stair to a place of safety. This does not apply if there are alternative escape routes from the foot of the external escape stair.
d. Stairs more than 6m in height should be protected from adverse weather. Protection should prevent the build-up of snow or ice but does not require full enclosure.
e. Glazing in areas of fire resisting construction should be fixed shut and fire resisting (in terms of integrity, but not insulation) (minimum E 30).
Any external escape stair should meet all of the following conditions (Diagram 3.11).
a. Doors to the stair should be fire resisting (minimum E 30) and be fitted with a self-closing device, except for a single exit door from the building to the top landing of a downward-leading external stair, provided it is the only door onto the landing.
b. Fire resisting construction (minimum RE 30) is required for the building envelope within the following zones, measured from the flights and landings of the external stair.
i. 1800mm above and horizontally.
ii. 9m vertically below.
iii. 1100mm above the top landing of the stair (except where the stair leads from basement to ground level).
c. Fire resisting construction (minimum RE 30) should be provided for any part of the building (including doors) within 1800mm of the escape route from the foot of the stair to a place of safety. This does not apply if there are alternative escape routes from the foot of the external escape stair.
d. Glazing in areas of fire resisting construction should be fixed shut and fire resisting (in terms of integrity but not insulation) (minimum E 30).
e. Stairs more than 6m in height above ground level (e.g. where they are provided above a podium) should be protected from adverse weather. Protection should prevent the build-up of snow or ice but does not require full enclosure.
Glazed elements should also comply with the following, where necessary.
a. If the enclosure forms part of a protected shaft: Section 7.
b. Appendix B, Table B5.
c. Guidance on the safety of glazing: Approved Document K.
Lift wells should comply with one of the following conditions.
a. Be sited within the enclosures of a protected stairway.
b. Be enclosed with fire resisting construction (minimum REI 30) when in a position that might prejudice the means of escape.
part f - ventilation
NOTE:
Ventilation ducts which serve other parts of the building should not supply or extract air directly to or from a protected escape route.
Ductwork enclosed in fire resisting construction classified EI X in accordance with BSEN13501-2 (fire exposure from the duct side), or fire resisting ductwork classified EIS X in accordance with BS EN 13501-3, where X is the fire resistance rating (in minutes) of the walls of the protected escape route
See para 9.16
ES leakage rated fire and smoke damper conforming to BS EN 13501-3/BS EN 1366-2
Smoke detection system in accordance with BS 5839-1 to activate ES damper
Ductwork passing through protected escape routes–method 4
NOTE:
Ventilation ducts which serve other parts of the building should not supply or extract air directly to or from a protected escape route.
See para 9.16
part q - security
In buildings with more than three storeys above the ground storey, stairs may serve the flats and other occupancies if all of the following apply.
a. The flat is ancillary to the main use of the building.
b. The flat has an independent alternative escape route.
c. The stair is separated from occupancies on lower storeys by a protected lobby (minimum REI 30) at each of those storeys.
d. The stair enclosure has at least the same standard of fire resistance as the structural elements of the building (see Appendix B, Table B4); if the stair is a firefighting stair, it should comply with the provisions in Section 15 (see also paragraph 3.60).
e. Any automatic fire detection and alarm system fitted in the main part of the building also covers all flats.
f. Any security measures in any parts of the building do not prevent escape at all material times.
perimeter (of a building)
This approved document has been published in two volumes. Volume 1 deals solely with dwellings, including blocks of flats, while Volume 2 deals with all other types of building covered by the Building Regulations
This approved document includes reference to selected guidance for buildings other than dwellings. For the design of mixed use buildings, Approved Document B Volume 2 should be consulted in addition to the guidance contained in this approved document.
Each basement space should have one or more smoke outlets.
Where this is not practicable (for example, the plan area is deep and the amount of external wall is restricted by adjoining buildings), the perimeter basement spaces may be vented, with other spaces vented indirectly by opening connecting doors. This does not apply for places of special fire hazard (see paragraph 16.7).
If a basement is compartmented, each compartment should have one or more smoke outlets, rather than indirect venting.
A basement storey or compartment containing rooms with doors or windows does not need smoke outlets.
Each basement space should have one or more smoke outlets.
Where this is not practicable (for example, the plan area is deep and the amount of external wall is restricted by adjoining buildings), the perimeter basement spaces may be vented, with other spaces vented indirectly by opening connecting doors. This does not apply for places of special fire hazard (see paragraph 16.7).
If a basement is compartmented, each compartment should have one or more smoke outlets, rather than indirect venting.
A basement storey or compartment containing rooms with doors or windows does not need smoke outlets.
permanent opening is a ventilation opening
The door of any doorway or exit should be hung to open in the direction of escape whenever reasonably practicable. It should always be hung to open in the direction of escape if more than 60 people might be expected to use it during a fire.
Where revolving doors, automatic doors and turnstiles are placed across escape routes they should comply with one of the following.
a. They are automatic doors of the required width and comply with one of the following conditions.
i. Their failsafe system provides outward opening from any open position.
ii. They have a monitored failsafe system to open the doors if the mains electricity supply fails.
iii. They failsafe to the open position if the power fails.
b. Non-automatic swing doors of the required width are provided immediately adjacent to the revolving or automatic door or turnstile.
permit
An inner room is permitted when it is one of the following.
a. A kitchen.
b. A laundry or utility room.
c. A dressing room.
d. A bathroom, WC or shower room.
e. Any room on a storey that is a maximum of 4.5m above ground level which is provided with an emergency escape window as described in paragraph 2.10.
f. A gallery that complies with paragraph 2.15.
For some low rise buildings, the provisions in paragraphs 3.26 and 3.27 may be modified and the use of a single stair, protected in accordance with Diagram 3.9, may be permitted where all of the following apply.
a. The top storey of the building is a maximum of 11m above ground level.
b. No more than three storeys are above the ground storey.
c. The stair does not connect to a covered car park, unless the car park is open sided (as defined in Section 11 of Approved Document B Volume 2).
d. The stair does not serve offices, stores or other ancillary accommodation. If it does, they should be separated from the stair by a protected lobby or protected corridor (minimum REI 30) with a minimum 0.4m2 of permanent ventilation, or be protected from the ingress of smoke by a mechanical smoke control system.
NOTE: For refuse chutes and storage see paragraphs 3.55 to 3.58.
e. Either of the following is provided for the fire and rescue service.
i. A high-level openable vent with a free area of at least 1m2 at each storey.
ii. A single openable vent with a free area of at least 1m2 at the head of the stair, operable remotely at the fire and rescue service access level.
An inner room is permitted when it is one of the following.
a. A kitchen.
b. A laundry or utility room.
c. A dressing room.
d. A bathroom, WC or shower room.
e. Any room on a storey that is a maximum of 4.5m above ground level which is provided with an emergency escape window as described in paragraph 3.6.
f. A gallery that complies with paragraph 3.13.
pipe
Gas service and installation pipes and meters should not be within a protected stairway, unless installed in accordance with the Pipelines Safety Regulations 1996 and the Gas Safety (Installation and Use) Regulations 1998.
Guidance on the control of flame spread is given in the following sections.
a. Stairs and landings: Sections 2 and 3 (escape stairs) and Section 15 (firefighting shafts).
b. Exposed surfaces above fire-protecting suspended ceilings: Section 8.
c. Enclosures to above-ground drainage system pipes: Section 9.
A protected shaft containing a protected stairway and/or a lift should not also contain either of the following.
a. A pipe that conveys oil, other than in the mechanism of a hydraulic lift.
b. A ventilating duct. Two exceptions are as follows.
i. A duct provided for pressurising the protected stairway to keep it smoke free.
ii. A duct provided only to ventilate the protected stairway.
A pipe that is completely separated from a protected shaft by fire resisting construction is not considered to be contained within that shaft.
In a protected shaft, any pipe carrying natural gas or LPG should be both of the following.
a. Of screwed steel or all-welded steel construction.
b. Installed in accordance with both of the following.
i. The Pipelines Safety Regulations 1996.
ii. The Gas Safety (Installation and Use) Regulations 1998.
A protected shaft conveying piped flammable gas should be ventilated direct to the outside air, by ventilation openings at high and low level in the shaft.
Any extension of the storey floor into the protected shaft should not compromise the free movement of air throughout the entire length of the shaft.
Guidance on shafts conveying piped flammable gas, including the size of ventilation openings, is given in BS 8313.
The external wall of a protected shaft does not normally need to have fire resistance. Situations where there are provisions are given in paragraph 3.63 (external walls of protected stairways, which may also be protected shafts) and paragraphs 15.8 to 15.11 (firefighting shafts).
Openings in other parts of the enclosure to a protected shaft should be limited to the following.
a. If a wall common to two or more buildings forms part of the enclosure, only the following openings should be made in that wall.
i. A fire doorset providing a means of escape, which has the same fire resistance as the wall and is fitted in accordance with the provisions in Appendix C.
ii. The passage of a pipe that meets the provisions in Section 9.
b. Other parts of the enclosure (other than an external wall) should only have openings for any of the following.
i. Fire doorsets of the appropriate fire resistance, fitted in accordance with the provisions in Appendix C.
ii. The passage of pipes which meet the provisions in Section 9.
iii. Inlets to, outlets from and openings for a ventilation duct (if the shaft contains or serves as a ventilating duct), meeting the provisions in Section 9.
iv. The passage of lift cables into a lift machine room (if the shaft contains a lift). If the machine room is at the bottom of the shaft, the openings should be as small as practicable.
NOTES:
1. The enclosure should meet all of the following conditions.
a. Be bounded by a compartment wall or floor, an outside wall, an intermediate floor or a casing(see specification at 2 below).
b. Have internal surfaces (except framing members)of class B-s3, d2 or better.
Note: when a classification includes ‘s3, d2’, this means that there is no limit set for smoke production and/or flaming droplets/particles).
c. Not have an access panel which opens into a circulation space or bed room.
d. Be used only for drainage or water supply or vent pipes for a drainage system.
2.The casing should meet all the following conditions.
a. Be imperforate except for an opening for a pipe
or an access panel.
b. Not be of sheet metal.
c. Not have fire resistance less than E 30 (including any access panel).
3.The opening for a pipe, in either the element of structure or the casing, should be as small as possible and fire-stopped around the pipe.
See para 9.4 and Table 9.1
NOTES:
1. Any metal (such as cast iron, copper or steel) which, if exposed to a temperature of 800°C, will not soften or fracture to the extent that flame or hot gas will pass through the wall of the pipe.
2. uPVC pipes that comply with either BS 4514 or BS 5255.
3. These diameters are only in relation to pipes that form part of an above-ground drainage system and are enclosed as shown in Diagram 9.1. In other cases, the maximum diameters given for situation 5 apply.
Pipes passing through a fire-separating element, unless in a protected shaft, should meet one of the alternatives A, B or C below.
NOTES:
1.Make the opening in the structure as small as possible and provide fire-stopping between pipe and structure.
2.See Table 9.1 for materials specification.
3. The sleeve should be class A1 rated.
See para 9.5
In addition to any other provisions in this section, both of the following conditions should be met.
a. Joints between fire-separating elements should be fire-stopped.
b. Openings through a fire resisting element for pipes, ducts, conduits or cable should be all of the following.
i. As few as possible.
ii. As small as practicable.
iii. Fire-stopped (allowing thermal movement in the case of a pipe or duct).
NOTE: The fire-stopping around fire dampers, fire resisting ducts, fire and smoke dampers and smoke control ducts should be in accordance with the manufacturer or supplier’s installation instructions.
Where a proprietary sealing system is not used, fire-stop around the pipe, keeping the opening for the pipe as small as possible. The nominal internal diameter of the pipe should not exceed the relevant dimension given in Table 9.1. The diameter given in Table 9.1 for pipes of specification (b) used in situation 2 or 3 assumes that the pipes are part of an above-ground drainage system and are enclosed as shown in Diagram 9.1. If they are not, the smaller diameter given for situation 5 should be used.
A pipe with a maximum nominal internal diameter of 160mm may be used with a sleeve made out of a high melting point metal, as shown in Diagram 9.2, if the pipe is made of one of the following.
a. Lead.
b. Aluminium.
c. Aluminium alloy.
d. Fibre-cement.
e. uPVC (pipes should also comply with either BS 4514 or BS 5255).
A high melting point metal means any metal (such as cast iron, copper or steel) which, if exposed to a temperature of 800°C, will not soften or fracture to the extent that flame or hot gas will pass through the wall of the pipe.
pitch
The unprotected area of the external wall of a stairway forming a protected shaft may be disregarded for separation distance purposes
Roofs pitched at an angle of less than 70 degrees may be disregarded for separation distance purposes
Represents an unprotected area of not more than 1m2 which may consist of two or more smaller areas within an area of 1000mm X 1000mm
Represents an area of not more than 0.1m2
See para 11.11
A ramp forming part of an escape route should meet the provisions in Approved Document M. Any sloping floor or tier should have a pitch of not more than 35 degrees to the horizontal.
pitch line
Flats
1. Within the enclosures of a protected entrance hall or protected landing, or within fire resisting separation shown in Section 3, Diagram 3.4.
2. Within either:
a. the enclosures of a protected stairway
b. fire resisting separation shown in Diagram 2.2.
3. Within fire resisting separation either:
a. shown in Diagram 2.4
b. described in paragraph 2.16b.
4. Existing window between an attached/integral garage and the dwellinghouse.
5. Adjacent to an external escape stair (see paragraph 2.17 and Diagram 2.7) or roof escape route (see paragraph 2.13).
6. Between residential/sleeping accommodation and a common escape route (corridor, lobby or stair).
7. Between a protected stairway(1)and either:
a. the accommodation
b. a corridor that is not a protected corridor other than in item 6 above.
8. Between either:
a. a protected stairway(1)and a protected lobby or protected corridor
b. accommodation and a protected lobby other than in item 6 above.
9. Between the accommodation and a protected corridor that forms a dead end,other than in item 6 above.
10.Between accommodation and any other corridor, or sub-dividing corridors,other than in item 6 above.
11. Beside an external escape route.
Table B5
see Table B3
Table B5
12. Beside an external escape stair (see paragraph 3.68 and Diagram 3.11) or roof escape route (see paragraph 3.30).
NOTES:
Items 1 and 8 apply also to single storey buildings.
Fire resisting glass should be marked with the name of the manufacturer and the name of the product.
Further guidance can be found in A Guide to Best Practice in the Specification and Use of Fire-resistant Glazed Systems published by the Glass and Glazing Federation.
1. If the protected stairway is also a protected shaft or a firefighting stair (see Section 15), there may be further
restrictions on the use of glazed elements.
2. Measured vertically from the landing floor level or the stair pitch line.
3. The 100mm limit is intended to reduce the risk of fire spreading from a floor covering.
Single steps on escape routes should be prominently marked. A single step on the line of a doorway is acceptable, subject to paragraph 3.107.
Travel distance is measured as the shortest route. Both of the following should be observed.
a. If there is fixed seating or other fixed obstructions, the shortest route is along the centre line of
the seatways and gangways.
b. If the route includes a stair, the shortest route is along the pitch line on the centre line of travel.
place of special fire hazard
Each fire hydrant should be clearly indicated by a plate, fixed nearby in a conspicuous position, in accordance with BS 3251.
Each basement space should have one or more smoke outlets.
Where this is not practicable (for example, the plan area is deep and the amount of external wall is restricted by adjoining buildings), the perimeter basement spaces may be vented, with other spaces vented indirectly by opening connecting doors. This does not apply for places of special fire hazard (see paragraph 16.7).
If a basement is compartmented, each compartment should have one or more smoke outlets, rather than indirect venting.
A basement storey or compartment containing rooms with doors or windows does not need smoke outlets.
Separate outlets should be provided from places of special fire hazard.
Final exits should avoid outlets of basement smoke vents and openings to transformer chambers, refuse chambers, boiler rooms and similar risks.
Where a stair serves an enclosed car park or place of special fire hazard, the lobby or corridor should have a minimum 0.4m2 of permanent ventilation or be protected from the ingress of smoke by a mechanical smoke control system.
NOTE: For refuse chutes and storage see paragraphs 3.55 to 3.58.
Insulating core panels consist of an inner core of insulation sandwiched between, and bonded to, a membrane, such as galvanised steel or aluminium.
Where they are used internally they can present particular problems with regard to fire spread and should meet all of the following conditions.
a. Panels should be sealed to prevent exposure of the core to a fire. This includes at joints and where services penetrate the panel.
b. In high fire risk areas, such as kitchens, places of special fire hazard, or in proximity to where hot works occur, only class A1 cored panels should be used.
c. Fixing systems for all panels should be designed to take account of the potential for the panel to delaminate. For instance, where panels are used to form a suspended ceiling, the fixing should pass through the panel and support it from the lower face.
If a loadbearing wall is any of the following, guidance in other sections may also apply.
a. A compartment wall (including a wall common to two buildings): Section 7.
b. Enclosing a place of special fire hazard: Section 7.
c. Protecting a means of escape: Sections 2 and 3.
d. An external wall: Sections 10 and 11.
e. Enclosing a firefighting shaft: Section 15.
plans certificates
If glazed elements in fire resisting enclosures and doors can only meet the required integrity performance, their use is limited. These limitations depend on whether the enclosure forms part of a protected shaft (see Section 7) and the provisions set out in Appendix B, Table B5. If both integrity and insulation performance can be met, there is no restriction in this document on the use or amount of glass.
Glazed elements should also comply with the following, where necessary.
a. If the enclosure forms part of a protected shaft: Section 7.
b. Appendix B, Table B5.
c. Guidance on the safety of glazing: Approved Document K.
platform floor
The following are excluded from the definition of ‘element of structure’.
a. A structure that supports only a roof, unless either of the following applies.
i. The roof performs the function of a floor, such as for parking vehicles, or as a means of escape.
ii. The structure is essential for the stability of an external wall that needs to be fire resisting (e.g. to achieve compartmentation or for the purposes of preventing fire spread between buildings).
b. The lowest floor of the building.
c. A platform floor.
d. External walls, such as curtain walls or other forms of cladding, which transmit only self weight and wind loads and do not transmit floor load.
NOTE: In some cases, structural members within a roof may be essential for the structural stability system of the building. In these cases, the structural members in the roof do not just support a roof and must demonstrate the relevant fire resistance for the building as required by the note to paragraph 6.1 above.
point of access
For dwellinghouses, access for a pumping appliance should be provided to within 45m of all points inside the dwellinghouse. Every elevation to which vehicle access is provided should have a suitable door(s), not less than 750mm wide, giving access to the interior of the building.
If the smoke outlet terminates at a point that is not readily accessible, it should be kept unobstructed and covered only with a class A1 grille or louvre.
Electrically powered locks should return to the unlocked position in all of the following situations.
a. If the fire detection and alarm system operates.
b. If there is loss of power or system error.
c. If the security mechanism override is activated.
Security mechanism overrides for electrically powered locks should be a Type A call point, as described in BS 7273-4. The call point should be positioned on the side approached by people escaping. If the door provides escape in either direction, a call point should be installed on both sides of the door.
power / electrical
Except for two storey blocks of flats, all escape routes should have adequate artificial lighting. If the mains electricity power supply fails, escape lighting should illuminate the route (including external escape routes).
pre-construction information
This section is a guide to the information that should be provided. Guidance is in terms of essential information and additional information for complex buildings; however, the level of detail required should be considered on a case-by-case basis.
prefabricated appliance chamber
Final exits should avoid outlets of basement smoke vents and openings to transformer chambers, refuse chambers, boiler rooms and similar risks.
prescriptive system
Fire resistance test criteria are set out in Appendix C. Standards of performance are summarised in Table C1.
presentation
Cavities in the construction of a building provide a ready route for the spread of smoke and flame, which can present a greater danger as any spread is concealed. For the purpose of this document, a cavity is considered to be any concealed space.
Cavities in the construction of a building provide a ready route for the spread of smoke and flame, which can present a greater danger as any spread is concealed. For the purpose of this document, a cavity is considered to be any concealed space.
pressure relief valve
All firefighting shafts should have fire mains with outlet connections and valves at every storey.
Guidance on the design of smoke control systems that use pressure differentials is available in BS EN 12101-6.
principal communal entrance
While many of the provisions in this approved document for means of escape from flats are applicable to sheltered housing, the nature of the occupancy may necessitate some additional fire protection measures. The extent of such measures will depend on the form of the development. For example, a group of specially adapted bungalows or two storey flats, with few communal facilities, will not need to be treated differently from other single storey or two storey dwellinghouses or flats.
In sheltered housing, the guidance in Approved Document B Volume 2 should be consulted for the design of communal facilities, such as a common lounge.
These provisions do not apply to the following.
a. The common parts of a sheltered housing development, such as communal lounges.
b. Sheltered accommodation in the 'residential (institutional)' or 'residential (other)' purpose groups (purpose group 2(a) or 2(b)).
In these parts, means of warning should follow the guidance for buildings other than dwellings in Volume 2 of Approved Document B.
One of the following approaches should be adopted, observing the inner room restrictions described in paragraphs 3.7 and 3.8.
a. Provide a protected entrance hall (minimum REI 30) serving all habitable rooms that meets the conditions shown in Diagram 3.2.
b. Plan the flat to meet the conditions shown in Diagram 3.3, so that both of the following apply.
i. The travel distance from the flat entrance door to any point in any habitable room is a maximum of 9m.
ii. Cooking facilities are remote from the main entrance door and do not impede the escape route from anywhere in the flat.
c. Provide an alternative exit from the flat complying with paragraph 3.19.
The provisions in this section make the following assumptions.
a. Any fire is likely to be in a flat.
b. There is no reliance on external rescue.
c. Simultaneous evacuation of all flats is unlikely to be necessary due to compartmentation.
d. Fires in common parts of the building should not spread beyond the fabric in the immediate vicinity. In some cases, however, communal facilities exist that require additional measures to be taken.
All fire doorsets, including to flat entrances and between a dwellinghouse and an integral garage,
should be fitted with a self-closing device, except for all of the following.
a. Fire doorsets to cupboards.
b. Fire doorsets to service ducts normally locked shut.
c. Fire doorsets within flats and dwellinghouses.
principal private entrance
Doors should be readily openable to avoid undue delay to people escaping. Doors on escape routes (both within and from the building) should comply with paragraphs 3.91 to 3.98. Guidance on door closing and ‘hold open’ devices for fire doorsets is set out in Appendix C.
NOTE: Paragraphs 3.91 to 3.98 do not apply to flat entrance doors.
principal storey
In buildings designed for phased evacuation or progressive horizontal evacuation, if the lift well is not within the enclosures of a protected stairway, its entrance should be separated at every storey by a protected lobby (minimum REI 30).
A lift shaft serving storeys above ground level should not serve any basement, if either of the following applies.
a. There is only one escape stair serving storeys above ground level and smoke from a basement fire would adversely affect escape routes in the upper storeys.
b. The lift shaft is within the enclosure to an escape stair that terminates at ground level.
principal works
People should be able to rapidly leave the area around the building. Direct access to a street, passageway, walkway or open space should be available. The route away from the building should comply with the following.
a. Be well defined.
b. If necessary, have suitable guarding.
Glazed elements should also comply with the following, where necessary.
a. If the enclosure forms part of a protected shaft: Section 7.
b. Appendix B, Table B5.
c. Guidance on the safety of glazing: Approved Document K.
Electrically powered locks should return to the unlocked position in all of the following situations.
a. If the fire detection and alarm system operates.
b. If there is loss of power or system error.
c. If the security mechanism override is activated.
Security mechanism overrides for electrically powered locks should be a Type A call point, as described in BS 7273-4. The call point should be positioned on the side approached by people escaping. If the door provides escape in either direction, a call point should be installed on both sides of the door.
private stair
Any alternative exit from a flat should comply with all of the following.
a. It should be remote from the main entrance door to the flat.
b. It should lead to a final exit, via a common stair if necessary, through one of the following.
i. A door to an access corridor, access lobby or common balcony.
ii. An internal private stair leading to an access corridor, access lobby or common balcony at another level.
iii. A door to a common stair.
iv. A door to an external stair.
v. A door to an escape route over a flat roof.
Any access route leading to a final exit or common stair should comply with the provisions for means of escape in the common parts of a flat (see paragraph 3.25).
The flights and landings of escape stairs should be constructed of materials achieving class A2-s3, d2 or better in all of the following situations.
a. If the escape stair is the only stair in a building with more than three storeys.
b. If the escape stair is within a basement storey.
c. If the escape stair serves any storey that has a floor level more than 18m above ground or access level.
d. If the escape stair is an external escape stair, except where the stair connects the ground storey or ground level with a floor or flat roof a maximum of 6m above or below ground level.
e. If the escape stair is a firefighting stair.
Materials achieving class B-s3, d2 or worse may be added to the top horizontal surface, except on firefighting stairs.
Further guidance on the construction of firefighting stairs is given in Section 15 (see also paragraph 3.60). Dimensional constraints on the design of stairs are given in Approved Document K.
Fixed ladders should not be provided as a means of escape for members of the public. They should only be provided where a conventional stair is impractical, such as for access to plant rooms which are not normally occupied.
Helical stairs and spiral stairs may form part of an escape route provided they are designed in accordance with BS 5395-2. If they are intended to serve members of the public, stairs should be type E (public) stairs.
Any door opening towards a corridor or a stair should be recessed to prevent its swing encroaching on the effective width.
project
Effective clear width (door stop to projecting ironmongery)
Effective clear width (door stop to door leaf)
Effective clear width (door stop to projecting ironmongery)
Effective clear width (door stop to door leaf)
If a protected stairway projects beyond, is recessed from or is in an internal angle of the adjoining external wall of the building, then the minimum distance between an unprotected area of the building enclosure and an unprotected area of the stair enclosure should be 1800mm.
project performance
If glazed elements in fire resisting enclosures and doors can only meet the required integrity performance, their use is limited. These limitations depend on whether the enclosure forms part of a protected shaft (see Section 7) and the provisions set out in Appendix B, Table B5. If both integrity and insulation performance can be met, there is no restriction in this document on the use or amount of glass.
protected circuit
In basements and enclosed car parks, the lift should be within the enclosure of a protected stairway. Otherwise, the lift should be approached only via a protected lobby or protected corridor (minimum REI 30).
If a lift delivers into a protected corridor or protected lobby serving sleeping accommodation and also serves a storey containing a high fire risk (such as a kitchen, communal areas, stores, etc.) then the lift should be separated from the high fire risk area(s) by a protected lobby or protected corridor (minimum REI 30).
To limit potential damage to cables in protected circuits, all of the following should apply.
a. Cables should be sufficiently robust.
b. Cable routes should be carefully selected and/or physically protected in areas where cables may be exposed to damage.
c. Methods of cable support should be class A1 rated and offer at least the same integrity as the cable. They should maintain circuit integrity and hold cables in place when exposed to fire.
A protected circuit to operate equipment during a fire should achieve all of the following.
a. Cables should achieve PH 30 classification when tested in accordance with BS EN 50200 (incorporating Annex E) or an equivalent standard.
b. It should only pass through parts of the building in which the fire risk is negligible.
c. It should be separate from any circuit provided for another purpose.
protected corridor/lobby
In buildings designed for phased evacuation or progressive horizontal evacuation, if the lift well is not within the enclosures of a protected stairway, its entrance should be separated at every storey by a protected lobby (minimum REI 30).
In basements and enclosed car parks, the lift should be within the enclosure of a protected stairway. Otherwise, the lift should be approached only via a protected lobby or protected corridor (minimum REI 30).
If a lift delivers into a protected corridor or protected lobby serving sleeping accommodation and also serves a storey containing a high fire risk (such as a kitchen, communal areas, stores, etc.) then the lift should be separated from the high fire risk area(s) by a protected lobby or protected corridor (minimum REI 30).
protected entrance hall/landing
Lift wells should comply with one of the following conditions.
a. Be sited within the enclosures of a protected stairway.
b. Be enclosed with fire resisting construction (minimum REI 30) when in a position that might prejudice the means of escape.
protected shaft
Exclude external walls of stairways in a protected shaft when assessing unprotected areas (see Diagram 11.5).
The unprotected area of the external wall of a stairway forming a protected shaft may be disregarded for separation distance purposes
Roofs pitched at an angle of less than 70 degrees may be disregarded for separation distance purposes
Represents an unprotected area of not more than 1m2 which may consist of two or more smaller areas within an area of 1000mm X 1000mm
Represents an area of not more than 0.1m2
See para 11.11
Firefighting shafts and protected stairways should be positioned such that every part of each storey more than 18m above the fire and rescue service vehicle access level complies with the maximum distances given in paragraph 15.7. Distances should be measured from the fire main outlet on a route suitable for laying a hose.
NOTE: If the internal layout is not known, the distance should be measured at two-thirds of the direct distance.
A lift well connecting different compartments should form a protected shaft (see Section 7).
Lift wells should comply with one of the following conditions.
a. Be sited within the enclosures of a protected stairway.
b. Be enclosed with fire resisting construction (minimum REI 30) when in a position that might prejudice the means of escape.
Fire resistance to protected shaft to be a maximum of REI 60
Fire resistance of construction to be a minimum of REI 30 (including fire doorsets that are a minimum of E 30 Sa)
Fire resistance of glazing to be a minimum of RE 30(including fire doorsets that are a minimum of E 30 Sa)
a. WITH CORRIDOR
b. WITH LOBBY
See para 7.25
Stairs and service shafts connecting compartments should be protected to restrict the spread of fire between the compartments. These are called protected shafts. Walls or floors surrounding a protected shaft are considered to be compartment walls or compartment floors.
Any stair or other shaft passing directly from one compartment to another should be enclosed in a protected shaft. Protected shafts should be used for the following only, but may also include sanitary accommodation and washrooms.
a. Stairs.
b. Lifts.
c. Escalators.
d. Chutes.
e. Ducts.
f. Pipes.
g. Additional provisions apply for both of the following.
i. Protected shafts that are protected stairways: Sections 2 to 4.
ii. Stairs that are also firefighting stairs: Section 15.
The construction enclosing a protected shaft (Diagram 7.1) should do all of the following.
a. Form a complete barrier to fire between the compartments connected by the shaft.
b. Have the appropriate fire resistance given in Appendix B, Table B3, except for uninsulated glazed screens that meet the provisions of paragraph 7.24.
c. Satisfy the provisions for ventilation and the treatment of openings in paragraphs 7.28 and 7.29.
An uninsulated glazed screen may be incorporated in the enclosure to a protected shaft between a stair and a lobby or corridor entered from the stair. The enclosure must conform to Diagram 7.2 and meet all of the following conditions.
a. The standard of fire resistance required for the protected stairway is not more than REI 60.
b. The glazed screen complies with the following.
i. It achieves a minimum rating of E 30.
ii. It complies with the guidance on limits on areas of uninsulated glazing in Appendix B, Table B5.
c. The lobby or corridor is enclosed with fire resisting construction achieving a minimum rating of REI 30.
A protected shaft containing a protected stairway and/or a lift should not also contain either of the following.
a. A pipe that conveys oil, other than in the mechanism of a hydraulic lift.
b. A ventilating duct. Two exceptions are as follows.
i. A duct provided for pressurising the protected stairway to keep it smoke free.
ii. A duct provided only to ventilate the protected stairway.
A pipe that is completely separated from a protected shaft by fire resisting construction is not considered to be contained within that shaft.
In a protected shaft, any pipe carrying natural gas or LPG should be both of the following.
a. Of screwed steel or all-welded steel construction.
b. Installed in accordance with both of the following.
i. The Pipelines Safety Regulations 1996.
ii. The Gas Safety (Installation and Use) Regulations 1998.
A protected shaft conveying piped flammable gas should be ventilated direct to the outside air, by ventilation openings at high and low level in the shaft.
Any extension of the storey floor into the protected shaft should not compromise the free movement of air throughout the entire length of the shaft.
Guidance on shafts conveying piped flammable gas, including the size of ventilation openings, is given in BS 8313.
The external wall of a protected shaft does not normally need to have fire resistance. Situations where there are provisions are given in paragraph 3.63 (external walls of protected stairways, which may also be protected shafts) and paragraphs 15.8 to 15.11 (firefighting shafts).
Openings in other parts of the enclosure to a protected shaft should be limited to the following.
a. If a wall common to two or more buildings forms part of the enclosure, only the following openings should be made in that wall.
i. A fire doorset providing a means of escape, which has the same fire resistance as the wall and is fitted in accordance with the provisions in Appendix C.
ii. The passage of a pipe that meets the provisions in Section 9.
b. Other parts of the enclosure (other than an external wall) should only have openings for any of the following.
i. Fire doorsets of the appropriate fire resistance, fitted in accordance with the provisions in Appendix C.
ii. The passage of pipes which meet the provisions in Section 9.
iii. Inlets to, outlets from and openings for a ventilation duct (if the shaft contains or serves as a ventilating duct), meeting the provisions in Section 9.
iv. The passage of lift cables into a lift machine room (if the shaft contains a lift). If the machine room is at the bottom of the shaft, the openings should be as small as practicable.
Pipes passing through a fire-separating element, unless in a protected shaft, should meet one of the alternatives A, B or C below.
protected stairway
Flats
1. Within the enclosures of a protected entrance hall or protected landing, or within fire resisting separation shown in Section 3, Diagram 3.4.
2. Within either:
a. the enclosures of a protected stairway
b. fire resisting separation shown in Diagram 2.2.
3. Within fire resisting separation either:
a. shown in Diagram 2.4
b. described in paragraph 2.16b.
4. Existing window between an attached/integral garage and the dwellinghouse.
5. Adjacent to an external escape stair (see paragraph 2.17 and Diagram 2.7) or roof escape route (see paragraph 2.13).
6. Between residential/sleeping accommodation and a common escape route (corridor, lobby or stair).
7. Between a protected stairway(1)and either:
a. the accommodation
b. a corridor that is not a protected corridor other than in item 6 above.
8. Between either:
a. a protected stairway(1)and a protected lobby or protected corridor
b. accommodation and a protected lobby other than in item 6 above.
9. Between the accommodation and a protected corridor that forms a dead end,other than in item 6 above.
10.Between accommodation and any other corridor, or sub-dividing corridors,other than in item 6 above.
11. Beside an external escape route.
Table B5
see Table B3
Table B5
12. Beside an external escape stair (see paragraph 3.68 and Diagram 3.11) or roof escape route (see paragraph 3.30).
NOTES:
Items 1 and 8 apply also to single storey buildings.
Fire resisting glass should be marked with the name of the manufacturer and the name of the product.
Further guidance can be found in A Guide to Best Practice in the Specification and Use of Fire-resistant Glazed Systems published by the Glass and Glazing Federation.
1. If the protected stairway is also a protected shaft or a firefighting stair (see Section 15), there may be further
restrictions on the use of glazed elements.
2. Measured vertically from the landing floor level or the stair pitch line.
3. The 100mm limit is intended to reduce the risk of fire spreading from a floor covering.
Exclude external walls of stairways in a protected shaft when assessing unprotected areas (see Diagram 11.5).
The unprotected area of the external wall of a stairway forming a protected shaft may be disregarded for separation distance purposes
Roofs pitched at an angle of less than 70 degrees may be disregarded for separation distance purposes
Represents an unprotected area of not more than 1m2 which may consist of two or more smaller areas within an area of 1000mm X 1000mm
Represents an area of not more than 0.1m2
See para 11.11
NOTES:
None of the above designations are suitable for protected stairways.
Polycarbonate and uPVC rooflights that achieve a class C-s3, d2 rating by test (see paragraph 12.7) may be regarded as having a BROOF(t4) classification.
Where Diagram 5.2a or 5.2b applies, rooflights should be a minimum of 1500mm from the compartment wall.
If double-skinned or laminate products have upper and lower surfaces of different materials, the greater distance applies.
1. See also the guidance to requirement B2 in Section 4.
2. The designation of external roof surfaces is explained in Appendix B.
3. Single-skinned rooflight only, in the case of non-thermoplastic material.
4. The rooflight should also meet the provisions of Diagram 12.1.
NOTES:
None of the above designations are suitable for protected stairways.
Polycarbonate and uPVC rooflights that achieve a class C-s3, d2 rating by test (paragraph 12.7) may be regarded as having a BROOF(t4) classification.
Where Diagram 5.2a or 5.2b applies, rooflights should be a minimum of 1500mm from the compartment wall.
If double-skinned or laminate products have upper and lower surfaces of different materials, the greater distance applies.
1. See also the guidance to requirement B2 in section 4.
2. No limit in the case of any space described in 2a, b and c.
3. Single-skinned rooflight only, in the case of non-thermoplastic material.
4. The rooflight should also meet the provisions of diagram 12.1.
The outlets from fire mains should be located within the protected stairway enclosure (see Diagram 15.1).
Firefighting shafts and protected stairways should be positioned such that every part of each storey more than 18m above the fire and rescue service vehicle access level complies with the maximum distances given in paragraph 15.7. Distances should be measured from the fire main outlet on a route suitable for laying a hose.
NOTE: If the internal layout is not known, the distance should be measured at two-thirds of the direct distance.
See para 2.5
Alternative cavity barrier arrangements in roof space over protected stairway in a house with a storey more than 4.5m above ground level
See Diagram 2.1c. The dwellinghouse should have either of the following. Cavity barriers or a fire resisting ceiling (minimum EI 30) should be provided above a protected stairway enclosure (Diagram 2.3). b. Alternative escape route – a top storey separated from lower storeys by fire resisting construction (minimum REI 30) and with an alternative escape route leading to its own final exit.
a. Protected stairway – a stair separated by fire resisting construction (minimum REI 30) at all storeys, that complies with one of the following.
i. Extends to a final exit (Diagram 2.2a).
ii. Gives access to a minimum of two ground level final exits that are separated from each other by fire resisting construction (minimum REI 30) and fire doorsets (minimum E 20) (Diagram 2.2b).
See Diagram 2.1d. In addition to meeting the provisions in paragraph 2.5, the dwellinghouse should comply with either of the following.
a. Provide an alternative escape route from each storey more than 7.5m above ground level. At the first storey above 7.5m, the protected stairway should be separated from the lower storeys by fire resisting construction (minimum REI 30) if the alternative escape route is accessed via either of the following.
i. The protected stairway to an upper storey.
ii. A landing within the protected stairway enclosure to an alternative escape route on the same storey. The protected stairway at or about 7.5m above ground level should be separated from the lower storeys or levels by fire resisting construction (see Diagram 2.4).
b. Provide a sprinkler system throughout, designed and installed in accordance with BS 9251.
All of the following precautions should be taken to avoid the spread of smoke and fire to the protected stairway.
a. Transfer grilles should not be fitted in any wall, door, floor or ceiling of the stair enclosure.
b. Any duct passing through the stair enclosure should be rigid steel. Joints between the ductwork and stair enclosure should be fire-stopped.
c. Ventilation ducts supplying or extracting air directly to or from a protected stairway should not serve other areas as well.
d. Any system of mechanical ventilation which recirculates air and which serves both the stair and other areas should be designed to shut down on the detection of smoke within the system.
e. For ducted warm air heating systems, a room thermostat should be sited in the living room. It should be mounted at a height between 1370mm and 1830mm above the floor. The maximum setting should be 27°C.
NOTE: Ventilation ducts passing through compartment walls should comply with the guidance in Section 9.
Configurations of stairs and external wall
Fire resisting construction
Fire resisting construction of adjacent building enclosure of protected stairway
Non-fire resisting construction
See para 3.63
Final exits should not present a barrier for disabled people. Where the route to a final exit does not include stairs, a level threshold and, where necessary, a ramp should be provided.
Final exit locations should be clearly visible and recognisable.
Final exits should avoid outlets of basement smoke vents and openings to transformer chambers, refuse chambers, boiler rooms and similar risks.
No fire resistance required for door
1100mm zone above top landing
1100mm zone above top landing
6m maximum height of stair
Fire resisting window (minimum RE30)
1800mm zone of fire resisting construction at side of stair
Fire doorset (minimum E30)
Ground level or a roof or podium served by an independent stairway
6m maximum height of stair without weather protection
9m zone of fire resisting construction below stair
Ground level or a roof or podium served by an independent stairway
See para 3.68
When multi-storey flats do not have their own external entrance at ground level, adopt one of the following approaches.
a. Approach 1 – provide at least one alternative exit from each habitable room that is not on the entrance storey of the flat (Diagram 3.5 and paragraph 3.22).
b. Approach 2 – provide at least one alternative exit from each storey that is not the entrance storey of the flat. All habitable rooms should have direct access to a protected landing (Diagram 3.6 and paragraph 3.22).
Approach 3 – provide a protected stairway plus a sprinkler system in accordance with Appendix E (smoke alarms should also be provided in accordance with Section 1).
d. Approach 4 – if the vertical distance between the entrance storey of the flat and any of the storeys above or below does not exceed 7.5m, provide all of the following.
i. A protected stairway.
ii. Additional smoke alarms in all habitable rooms.
iii. A heat alarm in any kitchen.
Every common stair should be a protected stairway. Where the protected stairway passes from one compartment to another, it should be within a protected shaft.
With some configurations of external wall, a fire in one part of a building could subject the external wall of a protected stairway to heat (for example, where the two are adjacent at an internal angle in the façade, as shown in Diagram 3.10).
If a protected stairway projects beyond, is recessed from or is in an internal angle of the adjoining external wall of the building, then the minimum distance between an unprotected area of the building enclosure and an unprotected area of the stair enclosure should be 1800mm.
The construction separating two adjacent protected stairways (or exit passageways leading to different final exits) should be imperforate.
A protected stairway should not be used for anything else, except a lift well or electricity meters.
Gas service and installation pipes and meters should not be within a protected stairway, unless installed in accordance with the Pipelines Safety Regulations 1996 and the Gas Safety (Installation and Use) Regulations 1998.
Every protected stairway should lead to a final exit, either directly or via a protected exit passageway. Any protected exit corridor or stair should have the same standard of fire resistance and lobby protection as the stair it serves.
Lift wells should comply with one of the following conditions.
a. Be sited within the enclosures of a protected stairway.
b. Be enclosed with fire resisting construction (minimum REI 30) when in a position that might prejudice the means of escape.
In rooms and circulation spaces other than protected stairways, rooflights may be constructed of thermoplastic material if they comply with both of the following.
a. The lower surface is classified as TP(a) rigid or TP(b).
b. The size and location of the rooflights follow the limits in Table 4.2, Table 12.2 and Table 12.3.
Diffusers constructed of thermoplastic material may be incorporated in ceilings to rooms and circulation spaces, but not to protected stairways, if both the following conditions are met.
a. Except for the upper surfaces of the thermoplastic panels, wall and ceiling surfaces exposed in the space above the suspended ceiling should comply with paragraph 4.1.
b. Diffusers should be classified as one of the following.
i. TP(a) rigid – no restrictions on their extent.
ii. TP(b) – limited in their extent (see Table 4.2 and Diagram 4.2).
Any stair or other shaft passing directly from one compartment to another should be enclosed in a protected shaft. Protected shafts should be used for the following only, but may also include sanitary accommodation and washrooms.
a. Stairs.
b. Lifts.
c. Escalators.
d. Chutes.
e. Ducts.
f. Pipes.
g. Additional provisions apply for both of the following.
i. Protected shafts that are protected stairways: Sections 2 to 4.
ii. Stairs that are also firefighting stairs: Section 15.
A protected shaft containing a protected stairway and/or a lift should not also contain either of the following.
a. A pipe that conveys oil, other than in the mechanism of a hydraulic lift.
b. A ventilating duct. Two exceptions are as follows.
i. A duct provided for pressurising the protected stairway to keep it smoke free.
ii. A duct provided only to ventilate the protected stairway.
A pipe that is completely separated from a protected shaft by fire resisting construction is not considered to be contained within that shaft.
The external wall of a protected shaft does not normally need to have fire resistance. Situations where there are provisions are given in paragraph 3.63 (external walls of protected stairways, which may also be protected shafts) and paragraphs 15.8 to 15.11 (firefighting shafts).
Openings in other parts of the enclosure to a protected shaft should be limited to the following.
a. If a wall common to two or more buildings forms part of the enclosure, only the following openings should be made in that wall.
i. A fire doorset providing a means of escape, which has the same fire resistance as the wall and is fitted in accordance with the provisions in Appendix C.
ii. The passage of a pipe that meets the provisions in Section 9.
b. Other parts of the enclosure (other than an external wall) should only have openings for any of the following.
i. Fire doorsets of the appropriate fire resistance, fitted in accordance with the provisions in Appendix C.
ii. The passage of pipes which meet the provisions in Section 9.
iii. Inlets to, outlets from and openings for a ventilation duct (if the shaft contains or serves as a ventilating duct), meeting the provisions in Section 9.
iv. The passage of lift cables into a lift machine room (if the shaft contains a lift). If the machine room is at the bottom of the shaft, the openings should be as small as practicable.
Ventilation ducts supplying or extracting air directly to or from a protected stairway should not also serve other areas. A separate ventilation system should be provided for each protected stairway.
proven
Further guidance on the construction of firefighting stairs is given in Section 15 (see also paragraph 3.60). Dimensional constraints on the design of stairs are given in Approved Document K.
purpose group
NOTES:
1.In assembly buildings (purpose group 5), a gallery is included as a storey, but not if it is a loading gallery, fly gallery, stage grid, lighting bridge, or any gallery provided for similar purposes, or for maintenance and repair.
2.In other purpose group buildings, galleries are not counted as a storey.
3.For the definition of basement, see Appendix A.
NOTES:
For single storey buildings, the periods under the heading ‘Up to 5’ apply. If single storey buildings have basements, for the basement storeys the period appropriate to their depth applies.
* For the floor over a basement or, if there is more than one basement, the floor over the topmost basement, the higher of the period for the basement storey and the period for the ground or upper storey applies.
† For compartment walls that separate buildings, the period is increased to a minimum of 60 minutes.
+ For any floor that does not contribute to the support of the building within a flat of more than one storey, the period is reduced to 30 minutes.
§ For flat conversions, refer to paragraphs 6.5 to 6.7 regarding the acceptability of 30 minutes.
‡ For elements that do not form part of the structural frame, the period is reduced to 90 minutes.
# For elements that protect the means of escape, the period is increased to 30 minutes.
1. Refer to note 1, Table B3 for the specific provisions of test.
2. Blocks of flats with a floor more than 30m above ground level should be fitted with a sprinkler system in accordance with Appendix E.
NOTE:
Sprinklers only need to be provided within the individual flats, they are not required in the common areas such as stairs, corridors or landings when these areas are fire sterile.
3.‘With sprinkler system’ means that the building is fitted throughout with an automatic sprinkler system in accordance with Appendix E.
4. Very large (over 18m in height or with a 10m deep basement) or unusual dwellinghouses are outside the scope of the guidance provided with regard to dwellinghouses.
5. A minimum of 30 minutes in the case of three storey dwellinghouses, increased to 60 minutes minimum for compartment walls separating buildings.
6. Buildings within the ‘office’, ‘shop and commercial’, ‘assembly and recreation’, ‘industrial’ and ‘storage and other non-residential’ (except car parks for light vehicles) purpose groups (purpose groups 3 to 7(a)) require sprinklers where there is a top storey above 30m.
The sprinkler system should be provided in accordance with Appendix E.
7. The car park should comply with the relevant provisions in the guidance on requirement B3, Section 11 of
Approved Document B Volume 2.
8. For the purposes of meeting the Building Regulations, the following types of steel elements are deemed to have satisfied the minimum period of fire resistance of 15 minutes when tested to the European test method.
i. Beams supporting concrete floors, maximum Hp/A=230m-1 operating under full design load.
ii. Free-standing columns, maximum Hp/A=180m-1 operating under full design load.
iii. Wind bracing and struts, maximum Hp/A=210m-1 operating under full design load.
Guidance is also available in BS EN 1993-1-2.
Volume 1 purpose groups
Purpose for which the building or compartment of a building is intended to be used
Residential(dwellings)
1(a)(1)Flat.
1(b)(2)Dwellinghouse that contains a habitable storey with a floor level a minimum of 4.5m above ground level up to a maximum of 18m.
(3)1(c)(2)(4)Dwellinghouse that does not contain a habitable storey with a floor level a minimum of 4.5m above ground level.
Building uses are classified within different purpose groups, which represent different levels of hazard (see Table 0.1). A purpose group can apply to a whole building or a compartment within the building, and should relate to the main use of the building or compartment.
Where a building or compartment has more than one use, it is appropriate to assign each different use to its own purpose group in the following situations.
a. If the ancillary use is a flat.
b. If both of the following apply.
i. The building or compartment has an area of more than 280m2.
ii. The ancillary use relates to an area that is more than one-fifth of the total floor area of the building or compartment.
c. In ‘shop and commercial’ (purpose group 4) buildings or compartments, if the ancillary use is storage and both of the following apply.
i. The building or compartment has an area of more than 280m2.
ii. The storage area comprises more than one-third of the total floor area of the building or compartment.
Where there are multiple main uses that are not ancillary to one another (for example, shops with independent offices above), each use should be assigned to a purpose group in its own right.
Where there is doubt as to which purpose group is appropriate, the more onerous guidance should be applied.
These provisions do not apply to the following.
a. The common parts of a sheltered housing development, such as communal lounges.
b. Sheltered accommodation in the 'residential (institutional)' or 'residential (other)' purpose groups (purpose group 2(a) or 2(b)).
In these parts, means of warning should follow the guidance for buildings other than dwellings in Volume 2 of Approved Document B.
In buildings that include a ‘residential’ purpose (purpose groups 1 and 2) with a storey 11m or more in height (see Diagram D6 in Appendix D) balconies should meet either of the following conditions.
a. Only contain materials achieving class A1 or A2-s1, d0, except for any of the following.
i. Cavity trays when used between two leaves of masonry.
ii. Intumescent and fire-stopping materials where the inclusion of the materials is necessary to meet the requirements of Part B of Schedule 1 to the Building Regulations 2010.
iii. Membranes.
iv. Seals, gaskets, fixings, sealants and backer rods.
v. Thermal break materials where the inclusion of the materials is necessary to meet the thermal bridging requirements of Part L of Schedule 1 to the Building Regulations 2010.
vi. Any material achieving class A1fl or A2fl-s1 when it forms the top horizontal floor layer of a balcony and is provided with an imperforate substrate under it which extends to the full size of the class A1fl or A2fl-s1 material.
vii. Electrical installations.
viii. Fibre optic cables.
b. Achieve both of the following conditions.
Have an imperforate soffit which extends to the full area of the balcony, achieves a minimum REI 30 rating and is constructed of materials achieving class A2-s1, d0 or better.
ii. Materials achieving class B-s1, d0 or worse extending beyond the boundary of a single
compartment should include a band of material rated class A2-s1, d0 or better, a minimum of 300mm in width centred on that boundary line.
Where regulation 7(2) applies, that regulation prevails over all the provisions in this paragraph.
In buildings that include a ‘residential’ purpose (purpose groups 1 and 2) with a storey 11m or more in height (see Diagram D6 in Appendix D) any insulation product, filler material (such as the core materials of metal composite panels, sandwich panels and window spandrel panels but not including gaskets, sealants and similar) etc. used in the construction of an external wall should be class A2-s1, d0 or better (see Appendix B). This restriction does not apply to masonry cavity wall construction which complies with Diagram 8.2 in Section 8. Where regulation 7(2) applies, that regulation prevails over all the provisions in this paragraph.
The following assumptions enable a reasonable standard of resistance to the spread of fire to be specified.
a. The size of a fire depends on the compartmentation within the building. A fire may involve a complete compartment, but will not spread to other compartments.
b. The intensity of a fire is related to the building use, but can be moderated by a sprinkler system.
c. Fires in ‘residential’ and ‘assembly and recreation’ buildings (purpose groups 1, 2 and 5) represent a greater risk to life.
d. A building on the far side of the relevant boundary meets both of the following conditions.
i. Has a similar elevation to the one in question.
ii. Is the same distance as the one in question from the common boundary.
e. The radiated heat passing through any part of the fire resisting external wall may be discounted.
The boundary that a wall faces is the relevant boundary (Diagram 11.2). It may be one of the following.
a. The site boundary.
b. The centre line of a space where further development is unlikely, such as a road, railway, canal or river.
c. An assumed notional boundary between two buildings on the same site (Diagram 11.3) where either of the following conditions is met.
i. One or both of the buildings are in the "residential" or "assembly and recreation" purpose groups (purpose group 1, 2 or 5).
ii. The buildings will be operated/managed by different organisations.
In blocks of flats (purpose group 1(a)) with a top storey over 18m above ground level (see Diagram D6 in Appendix D) an evacuation alert system should be provided in accordance with BS 8629.
Blocks of flats (purpose group 1(a)) with a top storey more than 11m above ground level (see Diagram D6 in Appendix D) should be provided with a secure information box.
NOTE: Consideration should also be given to other buildings with large, complex or uncommon layouts where the provision of a secure information box may be beneficial.
In mixed use buildings, separate means of escape should be provided from any storeys or parts of storeys used for the ‘residential’ or ‘assembly and recreation’ purpose groups (purpose groups 1, 2 and 5), other than in the case of certain small buildings or buildings in which the residential accommodation is ancillary (see paragraphs 3.76 and 3.77)
Materials achieving class B-s3, d2 or worse used as a substrate to the roof covering and any timber tiling battens, fully bedded in mortar or other suitable material for the width of the wall (Diagram 5.2b), may extend over the compartment wall in buildings that are both of the following.
a. A maximum of 15m high.
b. In one of the following purpose groups.
i. All residential purpose groups (purpose groups 1 and 2) other than ‘residential (institutional)’ (purpose group 2(a)).
ii. ‘Office’ (purpose group 3).
iii. ‘Assembly and recreation’ (purpose group 5).
The standards of fire resistance necessary for a particular building are based on assumptions about the severity of fires and the consequences should an element fail. Fire severity is estimated in very broad terms from the use of the building (its purpose group), on the assumption that the building contents (which constitute the fire load) are similar for buildings with the same use.
The following fire doorsets are not required to comply with paragraph C11.
a. Doors to and within flats and dwellinghouses.
b. Bedroom doors in ‘residential (other)’ (purpose group 2(b)) premises.
c. Lift entrance/landing doors.
radial gangway
Basic information on the location of fire protection measures may be sufficient. An as-built plan of the building should be provided showing all of the following.
a. Escape routes – this should include exit capacity (i.e. the maximum allowable number of people for each storey and for the building).
b. Location of fire-separating elements (including cavity barriers in walk-in spaces).
c. Fire doorsets, fire doorsets fitted with a self-closing device and other doors equipped with relevant hardware.
d. Locations of fire and/or smoke detector heads, alarm call points, detection/alarm control boxes, alarm sounders, fire safety signage, emergency lighting, fire extinguishers, dry or wet fire mains and other firefighting equipment, and hydrants outside the building.
e. Any sprinkler systems, including isolating valves and control equipment.
f. Any smoke control systems, or ventilation systems with a smoke control function, including mode of operation and control systems.
g. Any high risk areas (e.g. heating machinery).
The records should include details of all of the following.
d. All passive fire safety measures, including all of the following.
i. Compartmentation (i.e. location of fire-separating elements).
ii. Cavity barriers.
iii. Fire doorsets, including fire doorsets fitted with a self-closing device and other doors equipped with relevant hardware (e.g. electronic security locks).
iv. Duct dampers.
v. Fire shutters.
The records should include details of all of the following.
d. All passive fire safety measures, including all of the following.
iii. Fire doorsets, including fire doorsets fitted with a self-closing device and other doors equipped with relevant hardware (e.g. electronic security locks).
Divide a common corridor connecting two or more storey exits with a fire doorset fitted with a self-closing device (minimum E 30 Sa). See Diagram 3.8. Associated screens should be fire resisting. Site doors so that smoke does not affect access to more than one stair.
Except for doorsets listed in paragraph C12, all fire doorsets should be marked with one of the
following fire safety signs, complying with BS 5499-5, as appropriate.
a. To be kept closed when not in use – mark ‘Fire door keep shut’.
b. To be kept locked when not in use – mark ‘Fire door keep locked shut’.
c. Held open by an automatic release mechanism or free swing device – mark ‘Automatic fire door
keep clear’.
All fire doorsets should be marked on both sides, except fire doorsets to cupboards and service
ducts, which should be marked on the outside.
All fire doorsets, including to flat entrances and between a dwellinghouse and an integral garage,
should be fitted with a self-closing device, except for all of the following.
a. Fire doorsets to cupboards.
b. Fire doorsets to service ducts normally locked shut.
c. Fire doorsets within flats and dwellinghouses.
Two fire doorsets may be fitted in the same opening if each door is capable of closing the opening,
so the total fire resistance is the sum of their individual resistances. If the opening is provided as a
means of escape, both fire doorsets should be self-closing.
If one fire doorset is capable of being easily opened by hand and has a minimum of 30 minutes’ fire
resistance, the other fire doorset should comply with both of the following.
a. Be fitted with an automatic self-closing device.
b. Be held open by a fusible link.
ramp
A ramp forming part of an escape route should meet the provisions in Approved Document M. Any sloping floor or tier should have a pitch of not more than 35 degrees to the horizontal.
ramped
A ramp forming part of an escape route should meet the provisions in Approved Document M. Any sloping floor or tier should have a pitch of not more than 35 degrees to the horizontal.
record
A detailed record should be provided of both of the following.
a. The fire safety strategy.
b. Procedures for operating and maintaining any fire protection measures. This should include an outline cause and effect matrix/strategy for the building.
Further guidance is available in clause 9 and Annex H of BS 9999.
A detailed record should be provided of both of the following.
a. The fire safety strategy.
A detailed record should be provided of both of the following.
b. Procedures for operating and maintaining any fire protection measures. This should include an outline cause and effect matrix/strategy for the building.
Further guidance is available in clause 9 and Annex H of BS 9999.
The records should include details of all of the following. d. All passive fire safety measures, including all of the following. e. All of the following.
a. The fire safety strategy, including all assumptions in the design of the fire safety systems (such as fire load). Any risk assessments or risk analysis.
b. All assumptions in the design of the fire safety arrangements for the management of the building.
c. All of the following.
i. Escape routes (including occupant load and capacity of escape routes).
ii. Any provision to enable the evacuation of disabled people.
iii. Escape strategy (e.g. simultaneous or phased).
iv. Muster points.
i. Compartmentation (i.e. location of fire-separating elements).
ii. Cavity barriers.
iii. Fire doorsets, including fire doorsets fitted with a self-closing device and other doors equipped with relevant hardware (e.g. electronic security locks).
iv. Duct dampers.
v. Fire shutters.
i. Fire detector heads.
ii. Smoke detector heads.
iii. Alarm call points.
iv. Detection/alarm control boxes.
v. Alarm sounders.
vi. Emergency communications systems.
vii. CCTV.
viii. Fire safety signage.
ix. Emergency lighting.
x. Fire extinguishers.
xi. Dry or wet fire mains and other firefighting equipment.
xii. Other interior facilities for the fire and rescue service.
xiii. Emergency control rooms.
xiv. Location of hydrants outside the building.
xv. Other exterior facilities for the fire and rescue service.
f. All active fire safety measures, including both of the following.
i. Sprinkler system(s) design, including isolating valves and control equipment.
ii. Smoke control system(s) (or heating, ventilation and air conditioning system with a smoke control function) design, including mode of operation and control systems.
g. Any high risk areas (e.g. heating machinery) and particular hazards.
h. Plans of the building as built, showing the locations of the above.
i. Both of the following.
i. Specifications of any fire safety equipment provided, including all of the following.
• Operational details.
• Operators’ manuals.
• Software.
• System zoning.
• Routine inspection, testing and maintenance schedules.
ii. Records of any acceptance or commissioning tests.
j. Any other details appropriate for the specific building.
The records should include details of all of the following.
a. The fire safety strategy, including all assumptions in the design of the fire safety systems (such as fire load). Any risk assessments or risk analysis.
The records should include details of all of the following.
b. All assumptions in the design of the fire safety arrangements for the management of the building.
The records should include details of all of the following.
c. All of the following.
i. Escape routes (including occupant load and capacity of escape routes).
ii. Any provision to enable the evacuation of disabled people.
iii. Escape strategy (e.g. simultaneous or phased).
iv. Muster points.
The records should include details of all of the following.
d. All passive fire safety measures, including all of the following.
i. Compartmentation (i.e. location of fire-separating elements).
ii. Cavity barriers.
iii. Fire doorsets, including fire doorsets fitted with a self-closing device and other doors equipped with relevant hardware (e.g. electronic security locks).
iv. Duct dampers.
v. Fire shutters.
The records should include details of all of the following.
d. All passive fire safety measures, including all of the following.
i. Compartmentation (i.e. location of fire-separating elements).
The records should include details of all of the following.
d. All passive fire safety measures, including all of the following.
ii. Cavity barriers.
The records should include details of all of the following.
d. All passive fire safety measures, including all of the following.
iii. Fire doorsets, including fire doorsets fitted with a self-closing device and other doors equipped with relevant hardware (e.g. electronic security locks).
The records should include details of all of the following.
d. All passive fire safety measures, including all of the following.
iv. Duct dampers.
The records should include details of all of the following.
d. All passive fire safety measures, including all of the following.
iv. Duct dampers.
The records should include details of all of the following.
d. All passive fire safety measures, including all of the following.
v. Fire shutters.
The records should include details of all of the following.
e. All of the following.
i. Fire detector heads.
ii. Smoke detector heads.
iii. Alarm call points.
iv. Detection/alarm control boxes.
v. Alarm sounders.
vi. Emergency communications systems.
vii. CCTV.
viii. Fire safety signage.
ix. Emergency lighting.
x. Fire extinguishers.
xi. Dry or wet fire mains and other firefighting equipment.
xii. Other interior facilities for the fire and rescue service.
xiii. Emergency control rooms.
xiv. Location of hydrants outside the building.
xv. Other exterior facilities for the fire and rescue service.
The records should include details of all of the following.
f. All active fire safety measures, including both of the following.
i. Sprinkler system(s) design, including isolating valves and control equipment.
ii. Smoke control system(s) (or heating, ventilation and air conditioning system with a smoke control function) design, including mode of operation and control systems.
The records should include details of all of the following.
g. Any high risk areas (e.g. heating machinery) and particular hazards.
The records should include details of all of the following.
h. Plans of the building as built, showing the locations of the above.
The records should include details of all of the following.
i. Both of the following.
i. Specifications of any fire safety equipment provided, including all of the following.
• Operational details.
• Operators’ manuals.
• Software.
• System zoning.
• Routine inspection, testing and maintenance schedules.
ii. Records of any acceptance or commissioning tests.
The records should include details of all of the following.
i. Both of the following.
i. Specifications of any fire safety equipment provided, including all of the following.
• Operational details.
• Operators’ manuals.
• Software.
• System zoning.
• Routine inspection, testing and maintenance schedules.
The records should include details of all of the following.
i. Both of the following.
ii. Records of any acceptance or commissioning tests.
The records should include details of all of the following.
j. Any other details appropriate for the specific building.
regulation
Regulation 7(1A) prohibits the use of relevant metal composite materials in the external walls of all buildings of any height.
Regulation 7(1)(a) requires that materials used in building work are appropriate for the circumstances in which they are used. Regulation 7(2) sets requirements in respect of external walls and specified attachments in relevant buildings.
NOTE: Further guidance on regulation 7(1) can be found in HM Government’s Manual to the Building Regulations.
External walls and specified attachments are defined in regulation 2(6) and these definitions
include any parts of the external wall as well as balconies, solar panels and solar shading.
Regulation 7(3) provides an exemption for certain components found in external walls and specified attachments.
Regulations 5(k) and 6(3) provide that, where the use of a building is changed such that the building becomes a building described in regulation 7(4), the construction of the external walls, and specified attachments, must be investigated and, where necessary, work must be carried out to ensure they only contain materials achieving class A2-s1, d0 or class A1, other than those exempted by regulation 7(3).
Regulation 7(2) requires that the curtain and or slats of solar shading devices in a relevant building (as defined in regulation 7(4)) achieve class A1 or A2-s1, d0. The curtain of solar shading devices cannot be classified as a membrane in accordance with regulation 7(3).
Solar shading devices installed up to 4.5m above ground level are not required to meet the requirements of regulation 7(2).
The provisions of regulation 7 apply in addition to requirement B4. Therefore, for buildings described in regulation 7(4), the potential impact of any products incorporated into or onto the external walls and specified attachments should be carefully considered with regard to their number, size, orientation and position.
Where regulation 7(2) applies, that regulation prevails over the provisions within this section.
Gas service and installation pipes and meters should not be within a protected stairway, unless installed in accordance with the Pipelines Safety Regulations 1996 and the Gas Safety (Installation and Use) Regulations 1998.
regulation 38 fire safety information
The aim of this regulation is to ensure that the person responsible for the building has sufficient
information relating to fire safety to enable them to manage the building effectively. The aim of
regulation 38 will be achieved when the person responsible for the building has all the information
to enable them to do all of the following.
a. Understand and implement the fire safety strategy of the building.
b. Maintain any fire safety system provided in the building.
c. Carry out an effective fire risk assessment of the building.
The provisions in this document have the following aims.
Requirement B1: When there is a fire, ensure both:
a. satisfactory means of sounding an alarm
b. satisfactory means of escape for people.
Requirement B2: Inhibit the spread of fire over internal linings of buildings.
Requirement B3: The building must be built such that all of the following are achieved in the event of a fire:
a. the premature collapse of the building is avoided
b. sufficient fire separation is provided within buildings and between adjoining buildings
c. automatic fire suppression is provided where necessary
d. the unseen spread of fire and smoke in cavities is restricted.
Requirement B4: Restrict both:
a. the potential for fire to spread over external walls and roofs (including compliance with regulations 6(4) and 7(2))
b. the spread of fire from one building to another.
Requirement B5: Ensure both:
a. satisfactory access for the fire service and its appliances
b. facilities in buildings to help firefighters save the lives of people in and around buildings.
Regulation 38: Provide fire safety information to building owners.
regulation 7 - materials and workmanship
External fire spread
B4.(1)The external walls of the building shall adequately resist the spread of fire over the walls and from one building to another, having regard to the height, use and position of the building.
(2)The roof of the building shall adequately resist the spread of fire over the roof and from one building to another, having regard to the use and position of the building.
Regulation 7 – Materials and workmanship
(1)Building work shall be carried out—
(a)with adequate and proper materials which—
(i)are appropriate for the circumstances in which they are used,
(ii)are adequately mixed or prepared, and
(iii)are applied, used or fixed so as adequately to perform the functions for which they are designed; and
(b)in a workmanlike manner.
(2)Subject to paragraph (3), building work shall be carried out so that materials which become part of an external wall, or specified attachment, of a relevant building are of European Classification A2-s1, d0 or A1, classified in accordance with BS EN 13501-1:2007+A1:2009 entitled “Fire classification of construction products and building elements. Classification using test data from reaction to fire tests” (ISBN 978 0 580 59861 6) published by the British Standards Institution on 30th March 2007 and amended in November 2009.
(3)Paragraph (2) does not apply to—
(a)cavity trays when used between two leaves of masonry;
(b)any part of a roof (other than any part of a roof which falls within paragraph (iv) of regulation 2(6))if that part is connected to an external wall;
(c)door frames and doors;
(d)electrical installations;
(e)insulation and water proofing materials used below ground level;
(f)intumescent and fire stopping materials where the inclusion of the materials is necessary to meet the requirements of Part B of Schedule 1;
(g)membranes;
(h)seals, gaskets, fixings, sealants and backer rods;
(i)thermal break materials where the inclusion of the materials is necessary to meet the thermal bridging requirements of Part L of Schedule 1; or
(j)window frames and glass.
(4)In this regulation—
(a)a “relevant building” means a building with a storey (not including roof-top plant areas or any storey consisting exclusively of plant rooms) at least 18 metres above ground level and which—
(i)contains one or more dwellings;
(ii)contains an institution; or
(iii)contains a room for residential purposes(excluding any room in a hostel, hotel or boarding house); and
(b)“above ground level” in relation to a storey means above ground level when measured from the lowest ground level adjoining the outside of a building to the top of the floor surface of the storey.
Regulation 7(1)(a) requires that materials used in building work are appropriate for the circumstances in which they are used. Regulation 7(2) sets requirements in respect of external walls and specified attachments in relevant buildings.
NOTE: Further guidance on regulation 7(1) can be found in HM Government’s Manual to the Building Regulations.
Fire resistance test criteria are set out in Appendix C. Standards of performance are summarised in Table C1.
relevant boundary
The external surfaces (i.e. outermost external material) of external walls should comply with the provisions in Table 10.1. The provisions in Table 10.1 apply to each wall individually in relation to its proximity to the relevant boundary.
The following assumptions enable a reasonable standard of resistance to the spread of fire to be specified.
a. The size of a fire depends on the compartmentation within the building. A fire may involve a complete compartment, but will not spread to other compartments.
b. The intensity of a fire is related to the building use, but can be moderated by a sprinkler system.
c. Fires in ‘residential’ and ‘assembly and recreation’ buildings (purpose groups 1, 2 and 5) represent a greater risk to life.
d. A building on the far side of the relevant boundary meets both of the following conditions.
i. Has a similar elevation to the one in question.
ii. Is the same distance as the one in question from the common boundary.
e. The radiated heat passing through any part of the fire resisting external wall may be discounted.
Wall sufficiently distant from relevant boundary to be a 100% unprotected area
Wall on or very close to the relevant boundary: very limited amounts of unprotected area
Wall not on, or not very close to, but not sufficiently far from relevant boundary that it can be a wholly unprotected area
Amount of unprotected area dependent on distance from relevant boundary
See para 11.4
Where both of the following apply, separation distances may be determined from the wall rather than from the edge of the canopy (Diagram 11.6).
a. The canopy is attached to the side of a building.
b. The edges of the canopy are a minimum of 2m from the relevant boundary.
Canopies that fall within class 6 or class 7 of Schedule 2 to the regulations (Exempt Buildings and Work) are exempt from the Building Regulations.
Space separation may be disregarded if a canopy is all of the following.
a. Free-standing.
b. Above a limited risk or controlled hazard.
c. A minimum of 1000mm from the relevant boundary.
This boundary coincides with and is therefore relevant to side A
The boundary is parallel to side B2
But the relevant boundary may be the centre line of a road, railway, canal or river
NOTES:
This boundary is at less than 80 degrees to side C and is therefore relevant to side C
This diagram sets out the rules that apply in respect of a boundary for it to be considered as a relevant boundary.
For a boundary to be relevant it should comply with one of the following:
a. Coincide with the side of the building (A).
b. Be parallel to the side of the building (B1 or B2).
c. Be at an angle of maximum 80 degrees to the side of the building (C).
This boundary is parallel to and therefore relevant to side B1
See para 11.5
NOTES:
The notional boundary should be set in the area between the two buildings using the following rules:
1. The notional boundary is assumed to exist in the space between the buildings and is positioned so that one of the buildings would comply with the provisions for space separation having regard to the amount of its unprotected area. In practice, if one of the buildings is existing, the position of the boundary will be set by the space separation factors for that building.
2. The siting of the new building, or the second building if both are new, can then be checked to see that it also complies, using the notional boundary as the relevant boundary for the second building.
Notional boundary
Site boundary
Compliance with the provisions for space separation in respect of building A
Compliance with the provisions for space separation in respect of building B
See para 11.5
The fire resistance of a wall depends on its distance from the relevant boundary (see Diagram 11.1). Separation distances are measured to boundaries to ensure that the location and design of buildings on adjoining sites have no influence on the building under consideration.
The boundary that a wall faces is the relevant boundary (Diagram 11.2). It may be one of the following.
a. The site boundary.
b. The centre line of a space where further development is unlikely, such as a road, railway, canal or river.
c. An assumed notional boundary between two buildings on the same site (Diagram 11.3) where either of the following conditions is met.
i. One or both of the buildings are in the "residential" or "assembly and recreation" purpose groups (purpose group 1, 2 or 5).
ii. The buildings will be operated/managed by different organisations.
NOTE: Projections from the building line, such as a canopy or a loading platform, can be ignored when assessing separation distance. This does not apply where the canopy is enclosed by side walls.
Distance to relevant boundary measured from building line
See para 11.12
Minimum distance (a) between side of building and relevant boundary (m) Maximum total area of unprotected areas (m2)
See para 11.18
Separation distance is the minimum distance from the roof, or part of the roof, to the relevant boundary (paragraph 11.4). Table 12.1 sets out separation distances by the type of roof covering and the size and use of the building.
In addition, roof covering products (and/or materials) defined in Commission Decision 2000/553/ EC of 6 September 2000, implementing Council Directive 89/106/EEC, can be considered to fulfil all of the requirements for the performance characteristic ‘external fire performance’ without the need for testing, provided that any national provisions on the design and execution of works are fulfilled, and can be used without restriction.
If the performance of thatch or wood shingles cannot be established, they should be regarded as having an EROOF(t4) classification in Table 12.1.
NOTE: Consideration can be given to thatched roofs being closer to the relevant boundary than shown in Table 12.1 if, for example, all of the following precautions (based on the LABC publication Thatched Buildings (the Dorset Model): New Properties and Extensions) are incorporated in the design.
a. The rafters are overdrawn with construction having not less than 30 minutes’ fire resistance.
b. The guidance given in Approved Document J is followed.
c. The smoke alarm installation (see Section 1) extends to the roof spaces.
report
Guidance on the use of PTFE-based materials for tension-membrane roofs and structures is given in the BRE report BR 274.
research and development
Recommendations for the specification, design, construction, installation and maintenance of fire
doorsets constructed with non-metallic door leaves are given in BS 8214.
Guidance on timber fire resisting doorsets, in relation to the new European test standard, may be
found in Timber Fire Resisting Doorsets: Maintaining Performance Under the New European Test
Standard published by the Timber Research and Development Association (TRADA).
Guidance for metal doors is given in Code of Practice for Fire Resisting Metal Doorsets published by
the Door and Shutter Manufacturers’ Association (DSMA).
responsible person
Fire safety information 38.
(1) This regulation applies where building work—
(a) consists of or includes the erection or extension of a relevant building; or
(b) is carried out in connection with a relevant change of use of a building, and Part B of Schedule 1 imposes a requirement in relation to the work.
(2) The person carrying out the work shall give fire safety information to the responsible person not later than the date of completion of the work, or the date of occupation of the building or extension, whichever is the earlier.
(3) In this regulation—
(a) “fire safety information” means information relating to the design and construction of the building or extension, and the services, fittings and equipment provided in or in connection with the building or extension which will assist the responsible person to operate and maintain the building or extension with reasonable safety;
(b) a “relevant building” is a building to which the Regulatory Reform (Fire Safety) Order 2005 applies, or will apply after the completion of building work;
(c) a “relevant change of use” is a material change of use where, after the change of use takes place, the Regulatory Reform (Fire Safety) Order 2005 will apply, or continue to apply, to the building; and
(d) “responsible person” has the meaning given by article 3 of the Regulatory Reform (Fire Safety) Order 2005.
Fire safety information 38.
(1) This regulation applies where building work—
(a) consists of or includes the erection or extension of a relevant building; or
(b) is carried out in connection with a relevant change of use of a building, and Part B of Schedule 1 imposes a requirement in relation to the work.
(2) The person carrying out the work shall give fire safety information to the responsible person not later than the date of completion of the work, or the date of occupation of the building or extension, whichever is the earlier.
(3) In this regulation—
(a) “fire safety information” means information relating to the design and construction of the building or extension, and the services, fittings and equipment provided in or in connection with the building or extension which will assist the responsible person to operate and maintain the building or extension with reasonable safety;
(b) a “relevant building” is a building to which the Regulatory Reform (Fire Safety) Order 2005 applies, or will apply after the completion of building work;
(c) a “relevant change of use” is a material change of use where, after the change of use takes place, the Regulatory Reform (Fire Safety) Order 2005 will apply, or continue to apply, to the building; and
(d) “responsible person” has the meaning given by article 3 of the Regulatory Reform (Fire Safety) Order 2005.
The aim of this regulation is to ensure that the person responsible for the building has sufficient
information relating to fire safety to enable them to manage the building effectively. The aim of
regulation 38 will be achieved when the person responsible for the building has all the information
to enable them to do all of the following.
a. Understand and implement the fire safety strategy of the building.
b. Maintain any fire safety system provided in the building.
c. Carry out an effective fire risk assessment of the building.
The aim of this regulation is to ensure that the person responsible for the building has sufficient
information relating to fire safety to enable them to manage the building effectively. The aim of
regulation 38 will be achieved when the person responsible for the building has all the information
to enable them to do all of the following.
a. Understand and implement the fire safety strategy of the building.
b. Maintain any fire safety system provided in the building.
c. Carry out an effective fire risk assessment of the building.
For building work involving the erection or extension of a relevant building (i.e. a building to which the Regulatory Reform (Fire Safety) Order 2005 applies, or will apply), or the relevant change of use of a building, fire safety information should be given to the responsible person at one of the following times.
a. When the project is complete.
b. When the building or extension is first occupied.
rise
In low rise buildings without deep basements, access for firefighting personnel is typically achieved by providing measures for fire service vehicle access in Section 13 and means of escape.
For some low rise buildings, the provisions in paragraphs 3.26 and 3.27 may be modified and the use of a single stair, protected in accordance with Diagram 3.9, may be permitted where all of the following apply.
a. The top storey of the building is a maximum of 11m above ground level.
b. No more than three storeys are above the ground storey.
c. The stair does not connect to a covered car park, unless the car park is open sided (as defined in Section 11 of Approved Document B Volume 2).
d. The stair does not serve offices, stores or other ancillary accommodation. If it does, they should be separated from the stair by a protected lobby or protected corridor (minimum REI 30) with a minimum 0.4m2 of permanent ventilation, or be protected from the ingress of smoke by a mechanical smoke control system.
NOTE: For refuse chutes and storage see paragraphs 3.55 to 3.58.
e. Either of the following is provided for the fire and rescue service.
i. A high-level openable vent with a free area of at least 1m2 at each storey.
ii. A single openable vent with a free area of at least 1m2 at the head of the stair, operable remotely at the fire and rescue service access level.
risk assessment
The records should include details of all of the following. d. All passive fire safety measures, including all of the following. e. All of the following.
a. The fire safety strategy, including all assumptions in the design of the fire safety systems (such as fire load). Any risk assessments or risk analysis.
b. All assumptions in the design of the fire safety arrangements for the management of the building.
c. All of the following.
i. Escape routes (including occupant load and capacity of escape routes).
ii. Any provision to enable the evacuation of disabled people.
iii. Escape strategy (e.g. simultaneous or phased).
iv. Muster points.
i. Compartmentation (i.e. location of fire-separating elements).
ii. Cavity barriers.
iii. Fire doorsets, including fire doorsets fitted with a self-closing device and other doors equipped with relevant hardware (e.g. electronic security locks).
iv. Duct dampers.
v. Fire shutters.
i. Fire detector heads.
ii. Smoke detector heads.
iii. Alarm call points.
iv. Detection/alarm control boxes.
v. Alarm sounders.
vi. Emergency communications systems.
vii. CCTV.
viii. Fire safety signage.
ix. Emergency lighting.
x. Fire extinguishers.
xi. Dry or wet fire mains and other firefighting equipment.
xii. Other interior facilities for the fire and rescue service.
xiii. Emergency control rooms.
xiv. Location of hydrants outside the building.
xv. Other exterior facilities for the fire and rescue service.
f. All active fire safety measures, including both of the following.
i. Sprinkler system(s) design, including isolating valves and control equipment.
ii. Smoke control system(s) (or heating, ventilation and air conditioning system with a smoke control function) design, including mode of operation and control systems.
g. Any high risk areas (e.g. heating machinery) and particular hazards.
h. Plans of the building as built, showing the locations of the above.
i. Both of the following.
i. Specifications of any fire safety equipment provided, including all of the following.
• Operational details.
• Operators’ manuals.
• Software.
• System zoning.
• Routine inspection, testing and maintenance schedules.
ii. Records of any acceptance or commissioning tests.
j. Any other details appropriate for the specific building.
risk assessments
If a lift delivers into a protected corridor or protected lobby serving sleeping accommodation and also serves a storey containing a high fire risk (such as a kitchen, communal areas, stores, etc.) then the lift should be separated from the high fire risk area(s) by a protected lobby or protected corridor (minimum REI 30).
Final exits should avoid outlets of basement smoke vents and openings to transformer chambers, refuse chambers, boiler rooms and similar risks.
risk management
The Building Regulations do not impose any requirements on the management of a building, but do assume that it will be properly managed. This includes, for example, keeping protected escape routes virtually ‘fire sterile’.
Appropriate fire safety design considers the way in which a building will be managed. Any reliance on an unrealistic or unsustainable management regime cannot be considered to have met the requirements of the regulations.
Once the building is in use, the management regime should be maintained and a suitable risk assessment undertaken for any variation in that regime. Failure to take proper management responsibility may result in the prosecution of an employer, building owner or occupier under legislation such as the Regulatory Reform (Fire Safety) Order 2005.
roof
External fire spread
B4.(1)The external walls of the building shall adequately resist the spread of fire over the walls and from one building to another, having regard to the height, use and position of the building.
(2)The roof of the building shall adequately resist the spread of fire over the roof and from one building to another, having regard to the use and position of the building.
Regulation 7 – Materials and workmanship
(1)Building work shall be carried out—
(a)with adequate and proper materials which—
(i)are appropriate for the circumstances in which they are used,
(ii)are adequately mixed or prepared, and
(iii)are applied, used or fixed so as adequately to perform the functions for which they are designed; and
(b)in a workmanlike manner.
(2)Subject to paragraph (3), building work shall be carried out so that materials which become part of an external wall, or specified attachment, of a relevant building are of European Classification A2-s1, d0 or A1, classified in accordance with BS EN 13501-1:2007+A1:2009 entitled “Fire classification of construction products and building elements. Classification using test data from reaction to fire tests” (ISBN 978 0 580 59861 6) published by the British Standards Institution on 30th March 2007 and amended in November 2009.
(3)Paragraph (2) does not apply to—
(a)cavity trays when used between two leaves of masonry;
(b)any part of a roof (other than any part of a roof which falls within paragraph (iv) of regulation 2(6))if that part is connected to an external wall;
(c)door frames and doors;
(d)electrical installations;
(e)insulation and water proofing materials used below ground level;
(f)intumescent and fire stopping materials where the inclusion of the materials is necessary to meet the requirements of Part B of Schedule 1;
(g)membranes;
(h)seals, gaskets, fixings, sealants and backer rods;
(i)thermal break materials where the inclusion of the materials is necessary to meet the thermal bridging requirements of Part L of Schedule 1; or
(j)window frames and glass.
(4)In this regulation—
(a)a “relevant building” means a building with a storey (not including roof-top plant areas or any storey consisting exclusively of plant rooms) at least 18 metres above ground level and which—
(i)contains one or more dwellings;
(ii)contains an institution; or
(iii)contains a room for residential purposes(excluding any room in a hostel, hotel or boarding house); and
(b)“above ground level” in relation to a storey means above ground level when measured from the lowest ground level adjoining the outside of a building to the top of the floor surface of the storey.
Particular attention is drawn to the following points.
a. Membranes used as part of the external wall construction above ground level should achieve a minimum of class B-s3, d0. Roofing membranes do not need to achieve a minimum of class A2-s1, d0 when used as part of a roof connecting to an external wall.
b. Internal linings should comply with the guidance provided in Section 4.
c. Any part of a roof should achieve the minimum performance as detailed in Section 12.
d. As per regulation 7(3), window frames and glass (including laminated glass) are exempted
from regulation 7(2). Window spandrel panels and infill panels must comply with regulation 7(2).
e. Thermal breaks are small elements used as part of the external wall construction to restrict
thermal bridging. There is no minimum performance for these materials. However, they
should not span two compartments and should be limited in size to the minimum required
to restrict the thermal bridging (the principal insulation layer is not to be regarded as a
thermal break).
f. Regulation 7(2) only applies to specified attachments. Shop front signs and similar attachments are
not covered by the requirements of regulation 7(2), although attention is drawn to paragraph 10.21g.
g. While regulation 7(2) applies to materials which become part of an external wall or specified
attachment, consideration should be given to other attachments to the wall which could
impact on the risk of fire spread over the wall.
h. Any material achieving class A1fl or A2fl-s1 in accordance with BS EN 13501-1 is exempted when it
meets both of the following conditions.
i. It forms the top horizontal floor layer of a balcony.
ii. It is provided with an imperforate substrate under it which extends to the full size of the
class A1fl or A2fl-s1 material.
Best practice guidance for green walls (also called living walls) can be found in Fire Performance of Green Roofs and Walls, published by the Department for Communities and Local Government. Where regulation 7(2) applies, that regulation prevails over all the provisions in this paragraph.
The unprotected area of the external wall of a stairway forming a protected shaft may be disregarded for separation distance purposes
Roofs pitched at an angle of less than 70 degrees may be disregarded for separation distance purposes
Represents an unprotected area of not more than 1m2 which may consist of two or more smaller areas within an area of 1000mm X 1000mm
Represents an area of not more than 0.1m2
See para 11.11
‘Roof covering’ describes one or more layers of material, but not the roof structure as a whole.
NOTES:
Separation distances do not apply to the boundary between roofs of a pair of semi-detached dwellinghouses and to enclosed/covered walkways. However, see Diagram 5.2 if the roof passes over the top of a compartment wall.
Polycarbonate and uPVC rooflights that achieve a class C-s3, d2 rating by test may be regarded as having a BROOF(t4) designation.
1. The designation of external roof surfaces is explained in Appendix B.
2. Not acceptable on any of the following buildings.
a. Dwellinghouses in terraces of three or more dwellinghouses.
b. Any other buildings with a cubic capacity of more than 1500m3.
3. Acceptable on buildings not listed in (1) if both of the following apply.
a. Part of the roof has a maximum area of 3m2 and is a minimum of 1500mm from any similar part.
b. The roof between the parts is covered with a material rated class A2-s3, d2 or better.
Provisions for the fire properties of roofs are given in other parts of this document.
a. Requirement B1 – for roofs that are part of a means of escape.
b. Requirement B2 – for the internal surfaces of rooflights as part of internal linings.
c. Requirement B3 – for roofs that are used as a floor and for roofs passing over a compartment wall.
d. Section 11 – the circumstances in which a roof is subject to the provisions for space separation.
Separation distance is the minimum distance from the roof, or part of the roof, to the relevant boundary (paragraph 11.4). Table 12.1 sets out separation distances by the type of roof covering and the size and use of the building.
In addition, roof covering products (and/or materials) defined in Commission Decision 2000/553/ EC of 6 September 2000, implementing Council Directive 89/106/EEC, can be considered to fulfil all of the requirements for the performance characteristic ‘external fire performance’ without the need for testing, provided that any national provisions on the design and execution of works are fulfilled, and can be used without restriction.
If the performance of thatch or wood shingles cannot be established, they should be regarded as having an EROOF(t4) classification in Table 12.1.
NOTE: Consideration can be given to thatched roofs being closer to the relevant boundary than shown in Table 12.1 if, for example, all of the following precautions (based on the LABC publication Thatched Buildings (the Dorset Model): New Properties and Extensions) are incorporated in the design.
a. The rafters are overdrawn with construction having not less than 30 minutes’ fire resistance.
b. The guidance given in Approved Document J is followed.
c. The smoke alarm installation (see Section 1) extends to the roof spaces.
Where a flat roof forms part of a means of escape, it should comply with all of the following.
a. It should be part of the same building from which escape is being made.
b. The route across the roof should lead to a storey exit or external escape route.
c. The part of the roof (including its supporting structure) forming the escape route, and any opening within 3m of the escape route, should be of fire resisting construction (minimum REI 30).
See para 2.5
Alternative cavity barrier arrangements in roof space over protected stairway in a house with a storey more than 4.5m above ground level
Where a flat roof forms part of a means of escape, it should comply with all of the following.
a. It should be part of the same building from which escape is being made.
b. The route across the roof should lead to a storey exit or external escape route.
c. The part of the roof (including its supporting structure) forming the escape route, and any opening within 3m of the escape route, should be of fire resisting construction (minimum REI 30).
No fire resistance required for door
1100mm zone above top landing
1100mm zone above top landing
6m maximum height of stair
Fire resisting window (minimum RE30)
1800mm zone of fire resisting construction at side of stair
Fire doorset (minimum E30)
Ground level or a roof or podium served by an independent stairway
6m maximum height of stair without weather protection
9m zone of fire resisting construction below stair
Ground level or a roof or podium served by an independent stairway
See para 3.68
Where a storey or part of a building has multiple escape routes available, one may be over a flat roof that complies with all of the following.
a. It should be part of the same building from which escape is being made.
b. The route across the roof should lead to a storey exit or external escape route.
c. The part of the roof (including its supporting structure) forming the escape route, and any opening within 3m of the escape route, should be of fire resisting construction (minimum REI 30).
d. The route should be clearly defined and guarded by walls and/or protective barriers to protect against falling.
Where a storey or part of a building has multiple escape routes available, one may be over a flat roof that complies with all of the following.
d. The route should be clearly defined and guarded by walls and/or protective barriers to protect against falling.
Access to an external escape stair may be via a flat roof, provided the flat roof meets the requirements of paragraph 3.30.
For the purposes of this requirement, a ceiling includes all of the following.
a. Glazed surfaces.
b. Any part of a wall at 70 degrees or less to the horizontal.
c. The underside of a gallery.
d. The underside of a roof exposed to the room below.
Materials achieving class B-s3, d2 or worse used as a substrate to the roof covering and any timber tiling battens, fully bedded in mortar or other suitable material for the width of the wall (Diagram 5.2b), may extend over the compartment wall in buildings that are a maximum of 15m high.
Double-skinned insulated roof sheeting should incorporate a band of material rated class A2-s3, d2 or better, a minimum of 300mm in width, centred over the wall.
As an alternative to the provisions of paragraphs 5.12 to 5.14, the compartment wall may extend through the roof for a minimum of either of the following (see Diagram 5.2c).
a. Where the height difference between the two roofs is less than 375mm, 375mm above the top surface of the adjoining roof covering.
b. 200mm above the top surface of the adjoining roof covering where either of the following applies.
i. The height difference between the two roofs is 375mm or more.
ii. The roof coverings either side of the wall are of a material classified as BROOF(t4).
a. ANY BUILDING OR COMPARTMENT
Roof covering over this distance to be designated BROOF(t4) rated on deck of material of class A2-s3, d2 or better. Roof covering and deck could be composite structure, e.g. profiled steel cladding.
Fire-stopping to be carried up to underside of roof covering, boarding or slab.
Roof covering to be designated BROOF(t4) rated for at least 1500mm either side of wall.
b. RESIDENTIAL (DWELLINGS) AND RESIDENTIAL (OTHER) A MAXIMUM OF 15M HIGH
Boarding (used as a substrate) or timber tiling battens may be carried over the wall provided that they are fully bedded in mortar (or other no less suitable material) where over the wall.
Thermoplastic insulation materials should not be carried over the wall.
Double-skinned insulated roof sheeting with a thermoplastic core should incorporate a band of material of class A2-s3, d2 at least 300mm wide centred over the wall.
Sarking felt may also be carried over the wall.
If roof support members pass through the wall, fire protection to these members for a distance of 1500mm on either side of the wall may be needed to delay distortion at the junction (see paragraph 5.9).
Double-skinned insulated roof sheeting should incorporate a band of material rated class A2-s3, d2 or better, a minimum of 300mm in width, centred over the wall.
If roof support members pass through the wall, fire protection to these members for a distance of 1500mm on either side of the wall may be needed to delay distortion at the junction (see paragraph 5.9).
Fire-stopping to be carried up to underside of roof covering, e.g. roof tiles.
Section X–X
Roof covering to be designated BROOF(t4) rated for at least this distance.
Roofing battens and sarking felt may be carried over the wall.
Fire-stopping to be carried up to underside of roof covering above and below sarking felt.
NOTES:
1. Fire-stopping should be carried over the full thickness of the wall.
2. Fire-stopping should be extended into any eaves.
3. The compartment wall does not necessarily need to be constructed of masonry.
c. ANY BUILDING OR COMPARTMENT
The wall should be extended up through the roof for a height of at least 375mm above the top surface of the adjoining roof covering.
Where there is a height difference of at least 375mm between two roofs or where the roof coverings on either side of the wall are BROOF(t4) rated, the height of the upstand/parapet wall above the highest roof may be reduced to 200mm.
See paras 5.12 to 5.15
The following are excluded from the definition of ‘element of structure’.
a. A structure that supports only a roof, unless either of the following applies.
i. The roof performs the function of a floor, such as a roof terrace, or as a means of escape.
ii. The structure is essential for the stability of an external wall that needs to be fire resisting (e.g. to achieve compartmentation or for the purposes of preventing fire spread between buildings).
b. The lowest floor of the building.
c. External walls, such as curtain walls or other forms of cladding, which transmit only self weight and wind loads and do not transmit floor load.
NOTE: In some cases, structural members within a roof may be essential for the structural stability system of the building. In these cases, the structural members in the roof do not just support a roof and must demonstrate the relevant fire resistance for the building as required by paragraph 5.2 above.
The following are excluded from the definition of ‘element of structure’.
a. A structure that supports only a roof, unless either of the following applies.
i. The roof performs the function of a floor, such as for parking vehicles, or as a means of escape.
ii. The structure is essential for the stability of an external wall that needs to be fire resisting (e.g. to achieve compartmentation or for the purposes of preventing fire spread between buildings).
b. The lowest floor of the building.
c. A platform floor.
d. External walls, such as curtain walls or other forms of cladding, which transmit only self weight and wind loads and do not transmit floor load.
NOTE: In some cases, structural members within a roof may be essential for the structural stability system of the building. In these cases, the structural members in the roof do not just support a roof and must demonstrate the relevant fire resistance for the building as required by the note to paragraph 6.1 above.
Compartment walls in a top storey beneath a roof should be continued through the roof space.
Double-skinned insulated roof sheeting with a thermoplastic core should incorporate a band of material rated class A2-s3, d2 or better, a minimum of 300mm in width, centred over the wall.
As an alternative to the provisions of paragraph 7.16 or 7.17, the compartment wall may extend through the roof for a minimum of either of the following (see Diagram 5.2c).
a. Where the height difference between the two roofs is less than 375mm, 375mm above the top surface of the adjoining roof covering.
b. 200mm above the top surface of the adjoining roof covering where either of the following applies.
i. The height difference between the two roofs is 375mm or more.
ii. The roof coverings either side of the wall are of a material classified as BROOF(t4).
The insulation should make contact with both skins of sheeting. See also Diagram 5.2a regarding the need for fire-stopping where such roofs pass over the top of a compartment wall.
See para 8.7
Cavity barriers are not required between double-skinned corrugated or profiled insulated roof sheeting, if the sheeting complies with all of the following.
a. The sheeting is rated class A2-s3, d2 or better.
b. Both surfaces of the insulating layer are rated class C-s3, d2 or better.
c. Both surfaces of the insulating layer make contact with the inner and outer skins of cladding (Diagram 8.4).
Performance of the resistance of roofs to external fire exposure is measured in terms of penetration through the roof construction and the spread of flame over its surface.
Roof constructions are classified within the European system as BROOF(t4), CROOF(t4), DROOF(t4), EROOF(t4) or FROOF(t4) in accordance with BS EN 13501-5. BROOF(t4) indicates the highest performance and FROOF(t4) the lowest.
BS EN 13501-5 refers to four separate roof tests. The suffix (t4) used in paragraph B16 indicates that Test 4 is to be used for the purposes of this approved document.
This document uses the European classification system for roof covering set out in BS EN 13501-5; however, there may be some products lawfully on the market using the classification system set out in previous editions. Where this is the case, Table B2 can be used for the purposes of this document.
roof structure
‘Roof covering’ describes one or more layers of material, but not the roof structure as a whole.
Where a flat roof forms part of a means of escape, it should comply with all of the following.
a. It should be part of the same building from which escape is being made.
b. The route across the roof should lead to a storey exit or external escape route.
c. The part of the roof (including its supporting structure) forming the escape route, and any opening within 3m of the escape route, should be of fire resisting construction (minimum REI 30).
Where a flat roof forms part of a means of escape, it should comply with all of the following.
a. It should be part of the same building from which escape is being made.
b. The route across the roof should lead to a storey exit or external escape route.
c. The part of the roof (including its supporting structure) forming the escape route, and any opening within 3m of the escape route, should be of fire resisting construction (minimum REI 30).
Where a storey or part of a building has multiple escape routes available, one may be over a flat roof that complies with all of the following.
a. It should be part of the same building from which escape is being made.
b. The route across the roof should lead to a storey exit or external escape route.
c. The part of the roof (including its supporting structure) forming the escape route, and any opening within 3m of the escape route, should be of fire resisting construction (minimum REI 30).
d. The route should be clearly defined and guarded by walls and/or protective barriers to protect against falling.
Smoke vents should comply with one of the following.
a. They should be located on an external wall with minimum free area of 1.5m2.
b. They should discharge into a vertical smoke shaft, closed at the base, that meets all of the following criteria.
i. The shaft should conform to the following conditions.
• Have a minimum cross-sectional area of 1.5m2 (minimum dimension 0.85m in any direction).
• Open at roof level, minimum 0.5m above any surrounding structures within 2m of it horizontally.
• Extend a minimum of 2.5m above the ceiling of the highest storey served by the shaft.
ii. The free area of all the following vents should be a minimum of 1m2 in the following places.
• From the corridor or lobby into the shaft.
• At the opening at the head of the shaft.
• At all internal locations within the shaft (e.g. safety grilles).
iii. The smoke shaft should be constructed from a class A1 material. All vents should either be a smoke leakage (Sa) rated fire doorset (see Appendix C, Table C1, item 2.e for minimum fire resistance) or fitted with a smoke control damper achieving the same period of fire resistance and designed to operate as described below. The shaft should be vertical from base to head, with a maximum of 4m at a maximum inclined angle of 30 degrees.
iv. If smoke is detected in the common corridor or lobby, both of the following should occur.
• Simultaneous opening of vents on the storey where the fire is located, at the top of the smoke shaft and to the stair.
• Vents from the corridors or lobbies on all other storeys should remain closed, even if smoke is subsequently detected on storeys other than where the fire is located.
Guidance on the use of PTFE-based materials for tension-membrane roofs and structures is given in the BRE report BR 274.
a. ANY BUILDING OR COMPARTMENT
Roof covering over this distance to be designated BROOF(t4) rated on deck of material of class A2-s3, d2 or better. Roof covering and deck could be composite structure, e.g. profiled steel cladding.
Fire-stopping to be carried up to underside of roof covering, boarding or slab.
Roof covering to be designated BROOF(t4) rated for at least 1500mm either side of wall.
b. RESIDENTIAL (DWELLINGS) AND RESIDENTIAL (OTHER) A MAXIMUM OF 15M HIGH
Boarding (used as a substrate) or timber tiling battens may be carried over the wall provided that they are fully bedded in mortar (or other no less suitable material) where over the wall.
Thermoplastic insulation materials should not be carried over the wall.
Double-skinned insulated roof sheeting with a thermoplastic core should incorporate a band of material of class A2-s3, d2 at least 300mm wide centred over the wall.
Sarking felt may also be carried over the wall.
If roof support members pass through the wall, fire protection to these members for a distance of 1500mm on either side of the wall may be needed to delay distortion at the junction (see paragraph 5.9).
Double-skinned insulated roof sheeting should incorporate a band of material rated class A2-s3, d2 or better, a minimum of 300mm in width, centred over the wall.
If roof support members pass through the wall, fire protection to these members for a distance of 1500mm on either side of the wall may be needed to delay distortion at the junction (see paragraph 5.9).
Fire-stopping to be carried up to underside of roof covering, e.g. roof tiles.
Section X–X
Roof covering to be designated BROOF(t4) rated for at least this distance.
Roofing battens and sarking felt may be carried over the wall.
Fire-stopping to be carried up to underside of roof covering above and below sarking felt.
NOTES:
1. Fire-stopping should be carried over the full thickness of the wall.
2. Fire-stopping should be extended into any eaves.
3. The compartment wall does not necessarily need to be constructed of masonry.
c. ANY BUILDING OR COMPARTMENT
The wall should be extended up through the roof for a height of at least 375mm above the top surface of the adjoining roof covering.
Where there is a height difference of at least 375mm between two roofs or where the roof coverings on either side of the wall are BROOF(t4) rated, the height of the upstand/parapet wall above the highest roof may be reduced to 200mm.
See paras 5.12 to 5.15
The following are excluded from the definition of ‘element of structure’.
a. A structure that supports only a roof, unless either of the following applies.
i. The roof performs the function of a floor, such as a roof terrace, or as a means of escape.
ii. The structure is essential for the stability of an external wall that needs to be fire resisting (e.g. to achieve compartmentation or for the purposes of preventing fire spread between buildings).
b. The lowest floor of the building.
c. External walls, such as curtain walls or other forms of cladding, which transmit only self weight and wind loads and do not transmit floor load.
NOTE: In some cases, structural members within a roof may be essential for the structural stability system of the building. In these cases, the structural members in the roof do not just support a roof and must demonstrate the relevant fire resistance for the building as required by paragraph 5.2 above.
The following are excluded from the definition of ‘element of structure’.
a. A structure that supports only a roof, unless either of the following applies.
i. The roof performs the function of a floor, such as for parking vehicles, or as a means of escape.
ii. The structure is essential for the stability of an external wall that needs to be fire resisting (e.g. to achieve compartmentation or for the purposes of preventing fire spread between buildings).
b. The lowest floor of the building.
c. A platform floor.
d. External walls, such as curtain walls or other forms of cladding, which transmit only self weight and wind loads and do not transmit floor load.
NOTE: In some cases, structural members within a roof may be essential for the structural stability system of the building. In these cases, the structural members in the roof do not just support a roof and must demonstrate the relevant fire resistance for the building as required by the note to paragraph 6.1 above.
The following guidance should be used when applying the fire resistance standards in Table B4.
a. If one element of structure supports or carries or gives stability to another, the fire resistance
of the supporting element should be no less than the minimum period of fire resistance for the
other element (whether that other element is loadbearing or not). In some circumstances, it
may be reasonable to vary this principle, for example:
i. if the supporting structure is in the open air and is not likely to be affected by the fire in
the building
ii. if the supporting structure is in a different compartment, with a fire-separating element
(that has the higher standard of fire resistance) between the supporting and the separated
structure
iii. if a plant room on the roof needs greater fire resistance than the elements of structure
that support it.
b. If an element of structure forms part of more than one building or compartment, that element
should be constructed to the standard of the higher of the relevant provisions.
c. If, due to the slope of the ground, one side of a basement is open at ground level (allowing
smoke to vent and providing access for firefighting) for elements of structure in that storey
it may be appropriate to adopt the standard of fire resistance that applies to above-ground
structures.
d. Although most elements of structure in a single storey building may not need fire resistance,
fire resistance is needed if one of the following applies to the element.
i. It is part of, or supports, an external wall, and there is provision in the guidance on
requirement B4 to limit the extent of openings and other unprotected areas in the wall.
ii. It is part of, or supports, a compartment wall, including a wall that is common to two or
more buildings.
iii. It supports a gallery.
rooflight
a. Surface area: roofs and rooflights In each case measure the visible area
b. Floor area: Room, garage, conservatory or outbuilding, measure to inner surface of enclosing walls
c. Floor area: Storey, part or compartment, measure to inner surface of enclosing walls and include internal walls and partitions
NOTES:
1.There are restrictions on the use of plastic rooflights in the guidance to requirement B2 in Section 4.
2.Surrounding roof covering to be a material of class A2-s3, d3 or better for at least 3m distance.
3.Where Diagram 5.2a or 5.2b applies, rooflights should be at least 1500mm from the compartment wall.
See paras 12.5 and 12.6
NOTES:
Separation distances do not apply to the boundary between roofs of a pair of semi-detached dwellinghouses and to enclosed/covered walkways. However, see Diagram 5.2 if the roof passes over the top of a compartment wall.
Polycarbonate and uPVC rooflights that achieve a class C-s3, d2 rating by test may be regarded as having a BROOF(t4) designation.
1. The designation of external roof surfaces is explained in Appendix B.
2. Not acceptable on any of the following buildings.
a. Dwellinghouses in terraces of three or more dwellinghouses.
b. Any other buildings with a cubic capacity of more than 1500m3.
3. Acceptable on buildings not listed in (1) if both of the following apply.
a. Part of the roof has a maximum area of 3m2 and is a minimum of 1500mm from any similar part.
b. The roof between the parts is covered with a material rated class A2-s3, d2 or better.
Provisions for the fire properties of roofs are given in other parts of this document.
a. Requirement B1 – for roofs that are part of a means of escape.
b. Requirement B2 – for the internal surfaces of rooflights as part of internal linings.
c. Requirement B3 – for roofs that are used as a floor and for roofs passing over a compartment wall.
d. Section 11 – the circumstances in which a roof is subject to the provisions for space separation.
NOTES:
None of the above designations are suitable for protected stairways.
Polycarbonate and uPVC rooflights that achieve a class C-s3, d2 rating by test (see paragraph 12.7) may be regarded as having a BROOF(t4) classification.
Where Diagram 5.2a or 5.2b applies, rooflights should be a minimum of 1500mm from the compartment wall.
If double-skinned or laminate products have upper and lower surfaces of different materials, the greater distance applies.
1. See also the guidance to requirement B2 in Section 4.
2. The designation of external roof surfaces is explained in Appendix B.
3. Single-skinned rooflight only, in the case of non-thermoplastic material.
4. The rooflight should also meet the provisions of Diagram 12.1.
NOTES:
None of the above designations are suitable for protected stairways.
Polycarbonate and uPVC rooflights that achieve a class C-s3, d2 rating by test (paragraph 12.7) may be regarded as having a BROOF(t4) classification.
Where Diagram 5.2a or 5.2b applies, rooflights should be a minimum of 1500mm from the compartment wall.
If double-skinned or laminate products have upper and lower surfaces of different materials, the greater distance applies.
1. See also the guidance to requirement B2 in section 4.
2. No limit in the case of any space described in 2a, b and c.
3. Single-skinned rooflight only, in the case of non-thermoplastic material.
4. The rooflight should also meet the provisions of diagram 12.1.
The performance of rooflights is specified in a similar way to the performance of roof coverings. Plastic rooflights may also be used.
Table 12.2 and Diagram 12.1 set the limitations for using plastic rooflights whose lower surface has a minimum class D-s3, d2 rating.
Other than for the purposes of Diagram 5.2, polycarbonate or uPVC rooflights achieving a minimum rating of class C-s3, d2 can be regarded as having a BROOF(t4) classification.
When used in rooflights, unwired glass a minimum of 4mm thick can be regarded as having a BROOF(t4) classification.
In rooms and circulation spaces other than protected stairways, rooflights may be constructed of thermoplastic material if they comply with both of the following.
a. The lower surface is classified as TP(a) rigid or TP(b).
b. The size and location of the rooflights follow the limits in Table 4.2, Table 12.2 and Table 12.3.
NOTES:
1. Upper and lower surfaces of suspended ceiling, between plastic panels, to comply with paragraph 4.1.
2. No restriction on class D-s3, d2 diffusers or rooflights in small rooms.
3. See note 4 to Table 4.2. 5m²
See Table 4.2
NOTES:
1. This table does not apply to products that meet the provisions in Table 4.1.
2. Smaller rooflights and diffusers can be grouped together provided that both of the following satisfy the dimensions in Diagram 4.2 or 4.3.
a. The overall size of the group.
b. The space between one group and any others.
3. Lighting diffusers of TP(a) flexible rating should be used only in panels of a maximum of 5m2 each. See paragraph 4.17.
4. There are no limits on the use of class D-s3, d2 materials in small rooms. See Table 4.1.
5. The minimum 3m separation given in Diagram 4.2 between each 5m2 group must be maintained. Therefore, in some cases, it may not be possible to use the maximum percentage quoted.
Materials within this zone – at plane of ceiling – should comply with Table 4.1
Rooflights
See Table 4.2
For the purposes of this requirement, a ceiling does not include any of the following.
a. Trap doors and their frames.
b. The frames of windows or rooflights and frames in which glazing is fitted.
c. Architraves, cover moulds, picture rails, exposed beams and similar narrow members.
Rooflights should meet the following classifications, according to material. No guidance for European fire test performance is currently available, because there is no generally accepted test and classification procedure.
a. Non-plastic rooflights should meet the relevant classification in Table 4.1.
b. Plastic rooflights, if the limitations in Table 4.2 and Table 12.2 are observed, should be a minimum class D-s3, d2 rating. Otherwise they should meet the relevant classification in Table 4.1.
To reduce the risk of fire spreading over the roof from one compartment to another, a 1500mm wide zone of the roof, either side of the wall, should have a covering classified as BROOF(t4), on a substrate or deck of a material rated class A2-s3, d2 or better, as set out in Diagram 5.2a.
Thermoplastic rooflights that, because of paragraph 12.7, are regarded as having a BROOF(t4) classification are not suitable for use in that zone.
Thermoplastic materials used for window glazing, rooflights and lighting diffusers within suspended ceilings do not need to meet the criteria within paragraph B19 onwards, if the guidance to requirements B2 and B4 is followed.
room
Strong rooms do not need to be provided with smoke outlets.
Two rooms may be served by a single window. A door between the rooms should provide access to the window without passing through the stair enclosure. Both rooms should have their own access to the internal stair.
Two rooms may be served by a single escape window. A door between rooms should provide access to the escape window without passing through the stair enclosure. Both rooms should have their own access to the internal stair.
Fixed ladders should not be provided as a means of escape for members of the public. They should only be provided where a conventional stair is impractical, such as for access to plant rooms which are not normally occupied.
room for residential purposes
Regulation 7(2) applies to any building with a storey at least 18m above ground level (as
measured in accordance with Diagram D6 in Appendix D) and which contains one or more
dwellings; an institution; or a room for residential purposes. It requires that all materials which become part of an external wall or specified attachment achieve class A2-s1, d0 or class A1 in accordance with BS EN 13501-1, other than those exempted by regulation 7(3).
NOTE: The above includes student accommodation, care homes, sheltered housing, hospitals, dormitories in boarding schools, hotels, hostels and boarding houses. See regulation 7(4) for the definition of relevant buildings.
NOTE: Transposition to national class (Table B1) does not apply to the classification in this paragraph.
Final exits should avoid outlets of basement smoke vents and openings to transformer chambers, refuse chambers, boiler rooms and similar risks.
room-sealed appliance
People should be able to rapidly leave the area around the building. Direct access to a street, passageway, walkway or open space should be available. The route away from the building should comply with the following.
a. Be well defined.
b. If necessary, have suitable guarding.
Final exits should avoid outlets of basement smoke vents and openings to transformer chambers, refuse chambers, boiler rooms and similar risks.
safety case
Where Part B applies to existing buildings, particularly buildings of special architectural or historic interest for which the guidance in this document might prove too restrictive, some variation of the provisions in this document may be appropriate. In such cases, it is appropriate to assess the hazard and risk in the particular case and consider a range of fire safety features in that context.
sanitary accommodation
Any stair or other shaft passing directly from one compartment to another should be enclosed in a protected shaft. Protected shafts should be used for the following only, but may also include sanitary accommodation and washrooms.
a. Stairs.
b. Lifts.
c. Escalators.
d. Chutes.
e. Ducts.
f. Pipes.
g. Additional provisions apply for both of the following.
i. Protected shafts that are protected stairways: Sections 2 to 4.
ii. Stairs that are also firefighting stairs: Section 15.
Any stair or other shaft passing directly from one compartment to another should be enclosed in a protected shaft. Protected shafts should be used for the following only, but may also include sanitary accommodation and washrooms.
a. Stairs.
b. Lifts.
c. Escalators.
d. Chutes.
e. Ducts.
f. Pipes.
g. Additional provisions apply for both of the following.
i. Protected shafts that are protected stairways: Sections 2 to 4.
ii. Stairs that are also firefighting stairs: Section 15.
Counters and display units should be included when measuring area. All of the following should
be excluded.
a. Stair enclosures.
b. Lifts.
c. Sanitary accommodation.
d. Any other fixed part of the building structure.
sanitation hot water safety and water efficiency 2015 edition with 2016 amendments
Glazed elements should also comply with the following, where necessary.
a. If the enclosure forms part of a protected shaft: Section 7.
b. Appendix B, Table B5.
c. Guidance on the safety of glazing: Approved Document K.
Doors should contain vision panels in both of the following situations.
a. Where doors on escape routes divide corridors.
b. Where doors are hung to swing both ways.
Approved Document M contains guidance about vision panels in doors across accessible corridors and Approved Document K contains guidance about the safety of glazing.
schedule
The records should include details of all of the following.
i. Both of the following.
i. Specifications of any fire safety equipment provided, including all of the following.
• Operational details.
• Operators’ manuals.
• Software.
• System zoning.
• Routine inspection, testing and maintenance schedules.
ii. Records of any acceptance or commissioning tests.
The records should include details of all of the following.
i. Both of the following.
i. Specifications of any fire safety equipment provided, including all of the following.
• Operational details.
• Operators’ manuals.
• Software.
• System zoning.
• Routine inspection, testing and maintenance schedules.
Work should comply with Parts K and L of Schedule 1 to the Building Regulations. When complete, the building should comply with other applicable parts of Schedule 1 to at least the same level as before.
Work should comply with Parts K and L of Schedule 1 to the Building Regulations. When complete, the building should comply with other applicable parts of Schedule 1 to at least the same level as before.
schedule 1
Work should comply with Parts K and L of Schedule 1 to the Building Regulations. When complete, the building should comply with other applicable parts of Schedule 1 to at least the same level as before.
school
Regulation 7(2) applies to any building with a storey at least 18m above ground level (as
measured in accordance with Diagram D6 in Appendix D) and which contains one or more
dwellings; an institution; or a room for residential purposes. It requires that all materials which become part of an external wall or specified attachment achieve class A2-s1, d0 or class A1 in accordance with BS EN 13501-1, other than those exempted by regulation 7(3).
NOTE: The above includes student accommodation, care homes, sheltered housing, hospitals, dormitories in boarding schools, hotels, hostels and boarding houses. See regulation 7(4) for the definition of relevant buildings.
NOTE: Transposition to national class (Table B1) does not apply to the classification in this paragraph.
section
Requirements B1–B5 of Schedule 1 to the Building Regulations are dealt with separately in one or more sections. Each requirement is shown at the start of the relevant sections.
Requirements B1–B5 of Schedule 1 to the Building Regulations are dealt with separately in one or more sections. Each requirement is shown at the start of the relevant sections.
This section provides guidance on resisting fire spread over external walls; however, it does not deal with fire resistance of external walls. An external wall may need fire resistance to meet the provisions of Section 3 (Means of escape – flats), Section 6 (Loadbearing elements of structure – flats), Section 11 (Resisting fire spread from one building to another) or Section 15 (Access to buildings for firefighting personnel – flats).
Cavity barriers should be provided in accordance with Section 5 in dwellinghouses and Section 8 in flats.
Where regulation 7(2) applies, that regulation prevails over the provisions within this section.
In low rise buildings without deep basements, access for firefighting personnel is typically achieved by providing measures for fire service vehicle access in Section 13 and means of escape.
Best practice guidance can be found in Sections 2 to 4 of the Code of Practice for the Provision of Premises Information Boxes in Residential Buildings published by the Fire Industry Association (FIA).
If windows are replaced, it may be necessary to provide cavity barriers around the opening in accordance with Section 5.
A lift well connecting different compartments should form a protected shaft (see Section 7).
A multi-storey flat with an independent external entrance at ground level is similar to a dwellinghouse and means of escape should be planned on the basis of Section 2, depending on the height of the top storey above ground level.
Section 7 provides guidance on avoiding the spread of fire between storeys. For a stair that is also a firefighting stair, guidance in Section 15 should be followed.
Section 7 provides guidance on avoiding the spread of fire between storeys. For a stair that is also a firefighting stair, guidance in Section 15 should be followed.
Glazed elements should also comply with the following, where necessary.
a. If the enclosure forms part of a protected shaft: Section 7.
b. Appendix B, Table B5.
c. Guidance on the safety of glazing: Approved Document K.
Guidance on the control of flame spread is given in the following sections.
a. Stairs and landings: Sections 2 and 3 (escape stairs) and Section 15 (firefighting shafts).
b. Exposed surfaces above fire-protecting suspended ceilings: Section 8.
c. Enclosures to above-ground drainage system pipes: Section 9.
Guidance on the control of flame spread is given in the following sections.
a. Stairs and landings: Sections 2 and 3 (escape stairs) and Section 15 (firefighting shafts).
b. Exposed surfaces above fire-protecting suspended ceilings: Section 8.
c. Enclosures to above-ground drainage system pipes: Section 9.
Openings should be limited to the following.
a. Fire doorsets with a minimum E 30 rating, fitted in accordance with Appendix C.
b. The passage of pipes that follow the provisions in Section 9.
c. The passage of cables or conduits containing one or more cables.
d. Openings fitted with a suitably mounted and appropriate fire damper.
e. Ducts that are either of the following.
i. Fire resisting (minimum E 30).
ii. Fitted with a suitably mounted and appropriate fire damper where they pass through the cavity barrier.
NOTE: For further guidance on openings in cavity barriers see Section 9.
If a loadbearing wall is any of the following, guidance in other sections may also apply.
a. A compartment wall (including a wall common to two buildings): Section 7.
b. Enclosing a place of special fire hazard: Section 7.
c. Protecting a means of escape: Sections 2 and 3.
d. An external wall: Sections 10 and 11.
e. Enclosing a firefighting shaft: Section 15.
In a converted building with a maximum of three storeys, a minimum REI 30 fire resistance could be accepted for elements of structure if the means of escape conform to the provisions of Section 3.
section 1
Requirements B1–B5 of Schedule 1 to the Building Regulations are dealt with separately in one or more sections. Each requirement is shown at the start of the relevant sections.
This section provides guidance on resisting fire spread over external walls; however, it does not deal with fire resistance of external walls. An external wall may need fire resistance to meet the provisions of Section 3 (Means of escape – flats), Section 6 (Loadbearing elements of structure – flats), Section 11 (Resisting fire spread from one building to another) or Section 15 (Access to buildings for firefighting personnel – flats).
Where regulation 7(2) applies, that regulation prevails over the provisions within this section.
Section 7 provides guidance on avoiding the spread of fire between storeys. For a stair that is also a firefighting stair, guidance in Section 15 should be followed.
Guidance on the control of flame spread is given in the following sections.
a. Stairs and landings: Sections 2 and 3 (escape stairs) and Section 15 (firefighting shafts).
b. Exposed surfaces above fire-protecting suspended ceilings: Section 8.
c. Enclosures to above-ground drainage system pipes: Section 9.
Openings should be limited to the following.
a. Fire doorsets with a minimum E 30 rating, fitted in accordance with Appendix C.
b. The passage of pipes that follow the provisions in Section 9.
c. The passage of cables or conduits containing one or more cables.
d. Openings fitted with a suitably mounted and appropriate fire damper.
e. Ducts that are either of the following.
i. Fire resisting (minimum E 30).
ii. Fitted with a suitably mounted and appropriate fire damper where they pass through the cavity barrier.
NOTE: For further guidance on openings in cavity barriers see Section 9.
If a loadbearing wall is any of the following, guidance in other sections may also apply.
a. A compartment wall (including a wall common to two buildings): Section 7.
b. Enclosing a place of special fire hazard: Section 7.
c. Protecting a means of escape: Sections 2 and 3.
d. An external wall: Sections 10 and 11.
e. Enclosing a firefighting shaft: Section 15.
If a floor is also a compartment floor, see Section 7.
Further recommendations for the provision of sprinklers are provided in the following sections:
section 2
Requirements B1–B5 of Schedule 1 to the Building Regulations are dealt with separately in one or more sections. Each requirement is shown at the start of the relevant sections.
This section provides guidance on resisting fire spread over external walls; however, it does not deal with fire resistance of external walls. An external wall may need fire resistance to meet the provisions of Section 3 (Means of escape – flats), Section 6 (Loadbearing elements of structure – flats), Section 11 (Resisting fire spread from one building to another) or Section 15 (Access to buildings for firefighting personnel – flats).
Where regulation 7(2) applies, that regulation prevails over the provisions within this section.
Section 7 provides guidance on avoiding the spread of fire between storeys. For a stair that is also a firefighting stair, guidance in Section 15 should be followed.
Guidance on the control of flame spread is given in the following sections.
a. Stairs and landings: Sections 2 and 3 (escape stairs) and Section 15 (firefighting shafts).
b. Exposed surfaces above fire-protecting suspended ceilings: Section 8.
c. Enclosures to above-ground drainage system pipes: Section 9.
Openings should be limited to the following.
a. Fire doorsets with a minimum E 30 rating, fitted in accordance with Appendix C.
b. The passage of pipes that follow the provisions in Section 9.
c. The passage of cables or conduits containing one or more cables.
d. Openings fitted with a suitably mounted and appropriate fire damper.
e. Ducts that are either of the following.
i. Fire resisting (minimum E 30).
ii. Fitted with a suitably mounted and appropriate fire damper where they pass through the cavity barrier.
NOTE: For further guidance on openings in cavity barriers see Section 9.
If a loadbearing wall is any of the following, guidance in other sections may also apply.
a. A compartment wall (including a wall common to two buildings): Section 7.
b. Enclosing a place of special fire hazard: Section 7.
c. Protecting a means of escape: Sections 2 and 3.
d. An external wall: Sections 10 and 11.
e. Enclosing a firefighting shaft: Section 15.
If a floor is also a compartment floor, see Section 7.
Further recommendations for the provision of sprinklers are provided in the following sections:
secure doorset
Guidance on door closing and ‘hold open’ devices for fire doorsets is set out in Appendix C.
secure window
Windows or external doors providing emergency escape should comply with all of the following.
a. Windows should have an unobstructed openable area that complies with all of the following.
i. A minimum area of 0.33m2.
ii. A minimum height of 450mm and a minimum width of 450mm (the route through the window may be at an angle rather than straight through).
iii. The bottom of the openable area is a maximum of 1100mm above the floor.
b. People escaping should be able to reach a place free from danger from fire. Courtyards or inaccessible back gardens should comply with Diagram 2.5.
c. Locks (with or without removable keys) and opening stays (with child-resistant release catches) may be fitted to escape windows.
d. Windows should be capable of remaining open without being held.
Access openings to refuse storage chambers should not be sited in the following areas.
a. Next to escape routes or final exits.
b. Near the windows of flats.
Windows or external doors providing emergency escape should comply with all of the following.
a. Windows should have an unobstructed openable area that complies with all of the following.
i. A minimum area of 0.33m2.
ii. A minimum height of 450mm and a minimum width of 450mm (the route through the window may be at an angle rather than straight through).
iii. The bottom of the openable area is a maximum of 1100mm above the floor.
b. People escaping should be able to reach a place free from danger from fire.
c. Locks (with or without removable keys) and opening stays (with child-resistant release catches) may be fitted to escape windows.
d. Windows should be capable of remaining open without being held.
self-closing device
Basic information on the location of fire protection measures may be sufficient. An as-built plan of the building should be provided showing all of the following.
a. Escape routes – this should include exit capacity (i.e. the maximum allowable number of people for each storey and for the building).
b. Location of fire-separating elements (including cavity barriers in walk-in spaces).
c. Fire doorsets, fire doorsets fitted with a self-closing device and other doors equipped with relevant hardware.
d. Locations of fire and/or smoke detector heads, alarm call points, detection/alarm control boxes, alarm sounders, fire safety signage, emergency lighting, fire extinguishers, dry or wet fire mains and other firefighting equipment, and hydrants outside the building.
e. Any sprinkler systems, including isolating valves and control equipment.
f. Any smoke control systems, or ventilation systems with a smoke control function, including mode of operation and control systems.
g. Any high risk areas (e.g. heating machinery).
The records should include details of all of the following. d. All passive fire safety measures, including all of the following. e. All of the following.
a. The fire safety strategy, including all assumptions in the design of the fire safety systems (such as fire load). Any risk assessments or risk analysis.
b. All assumptions in the design of the fire safety arrangements for the management of the building.
c. All of the following.
i. Escape routes (including occupant load and capacity of escape routes).
ii. Any provision to enable the evacuation of disabled people.
iii. Escape strategy (e.g. simultaneous or phased).
iv. Muster points.
i. Compartmentation (i.e. location of fire-separating elements).
ii. Cavity barriers.
iii. Fire doorsets, including fire doorsets fitted with a self-closing device and other doors equipped with relevant hardware (e.g. electronic security locks).
iv. Duct dampers.
v. Fire shutters.
i. Fire detector heads.
ii. Smoke detector heads.
iii. Alarm call points.
iv. Detection/alarm control boxes.
v. Alarm sounders.
vi. Emergency communications systems.
vii. CCTV.
viii. Fire safety signage.
ix. Emergency lighting.
x. Fire extinguishers.
xi. Dry or wet fire mains and other firefighting equipment.
xii. Other interior facilities for the fire and rescue service.
xiii. Emergency control rooms.
xiv. Location of hydrants outside the building.
xv. Other exterior facilities for the fire and rescue service.
f. All active fire safety measures, including both of the following.
i. Sprinkler system(s) design, including isolating valves and control equipment.
ii. Smoke control system(s) (or heating, ventilation and air conditioning system with a smoke control function) design, including mode of operation and control systems.
g. Any high risk areas (e.g. heating machinery) and particular hazards.
h. Plans of the building as built, showing the locations of the above.
i. Both of the following.
i. Specifications of any fire safety equipment provided, including all of the following.
• Operational details.
• Operators’ manuals.
• Software.
• System zoning.
• Routine inspection, testing and maintenance schedules.
ii. Records of any acceptance or commissioning tests.
j. Any other details appropriate for the specific building.
The records should include details of all of the following.
d. All passive fire safety measures, including all of the following.
i. Compartmentation (i.e. location of fire-separating elements).
ii. Cavity barriers.
iii. Fire doorsets, including fire doorsets fitted with a self-closing device and other doors equipped with relevant hardware (e.g. electronic security locks).
iv. Duct dampers.
v. Fire shutters.
The records should include details of all of the following.
d. All passive fire safety measures, including all of the following.
iii. Fire doorsets, including fire doorsets fitted with a self-closing device and other doors equipped with relevant hardware (e.g. electronic security locks).
Divide a common corridor connecting two or more storey exits with a fire doorset fitted with a self-closing device (minimum E 30 Sa). See Diagram 3.8. Associated screens should be fire resisting. Site doors so that smoke does not affect access to more than one stair.
A fire doorset (minimum E 30 Sa) fitted with a self-closing device (and fire resisting screen, where required) should separate the dead-end portion of a common corridor from the rest of the corridor (Diagrams 3.7a, 3.8b and 3.8c).
Any external escape stair should meet all of the following conditions (Diagram 3.11).
a. Doors to the stair should be fire resisting (minimum E 30) and be fitted with a self-closing device, except for a single exit door from the building to the top landing of a downward-leading external stair, provided it is the only door onto the landing.
b. Fire resisting construction (minimum RE 30) is required for the building envelope within the following zones, measured from the flights and landings of the external stair.
i. 1800mm above and horizontally.
ii. 9m vertically below.
iii. 1100mm above the top landing of the stair (except where the stair leads from basement to ground level).
c. Fire resisting construction (minimum RE 30) should be provided for any part of the building (including doors) within 1800mm of the escape route from the foot of the stair to a place of safety. This does not apply if there are alternative escape routes from the foot of the external escape stair.
d. Glazing in areas of fire resisting construction should be fixed shut and fire resisting (in terms of integrity but not insulation) (minimum E 30).
e. Stairs more than 6m in height above ground level (e.g. where they are provided above a podium) should be protected from adverse weather. Protection should prevent the build-up of snow or ice but does not require full enclosure.
Doors should be readily openable to avoid undue delay to people escaping. Doors on escape routes (both within and from the building) should comply with paragraphs 3.91 to 3.98. Guidance on door closing and ‘hold open’ devices for fire doorsets is set out in Appendix C.
NOTE: Paragraphs 3.91 to 3.98 do not apply to flat entrance doors.
Guidance on door closing and ‘hold open’ devices for fire doorsets is set out in Appendix C.
Any door opening towards a corridor or a stair should be recessed to prevent its swing encroaching on the effective width.
Doors should contain vision panels in both of the following situations.
a. Where doors on escape routes divide corridors.
b. Where doors are hung to swing both ways.
Approved Document M contains guidance about vision panels in doors across accessible corridors and Approved Document K contains guidance about the safety of glazing.
Where revolving doors, automatic doors and turnstiles are placed across escape routes they should comply with one of the following.
a. They are automatic doors of the required width and comply with one of the following conditions.
i. Their failsafe system provides outward opening from any open position.
ii. They have a monitored failsafe system to open the doors if the mains electricity supply fails.
iii. They failsafe to the open position if the power fails.
b. Non-automatic swing doors of the required width are provided immediately adjacent to the revolving or automatic door or turnstile.
Fire doors between the garage and dwellinghouse to have a minimum fire resistance of E30 Sa and be fitted with a self-closing device
Wall and any floor between the garage and dwellinghouse to have a minimum fire resistance of REI 30 from the garage side
The door opening threshold should be a minimum of 100mm above garage floor or
Floor to fall away from door to the outside
See paras 5.6 and 5.7
All fire doorsets, including to flat entrances and between a dwellinghouse and an integral garage,
should be fitted with a self-closing device, except for all of the following.
a. Fire doorsets to cupboards.
b. Fire doorsets to service ducts normally locked shut.
c. Fire doorsets within flats and dwellinghouses.
If a self-closing device would be considered to interfere with the normal approved use of the
building, self-closing fire doors may be held open by one of the following.
a. A fusible link, but not if the doorset is in an opening provided as a means of escape unless it
complies with paragraph C7.
b. An automatic release mechanism activated by an automatic fire detection and alarm system.
c. A door closer delay device.
Two fire doorsets may be fitted in the same opening if each door is capable of closing the opening,
so the total fire resistance is the sum of their individual resistances. If the opening is provided as a
means of escape, both fire doorsets should be self-closing.
If one fire doorset is capable of being easily opened by hand and has a minimum of 30 minutes’ fire
resistance, the other fire doorset should comply with both of the following.
a. Be fitted with an automatic self-closing device.
b. Be held open by a fusible link.
separated part
In every case measure the volume contained by all of the following.
a. Under surface of roof.
b. Upper surface of lowest floor.
c. Inner surface of enclosing walls.
When there is not an outer enclosingwall, measure to the outermost edge of the floor slab.
The measured volume should include internal walls and partitions.
a. Cubic capacity of a building Internal wall or partition
b. Cubic capacity of compartments or separated part of a building
Diagram D2 Cubic capacity
Each flat in a block should have alarms as set out in paragraphs 1.1 to 1.4. With effective compartmentation, a communal fire alarm system is not normally needed. In some buildings, detectors in common parts of the building may need to operate smoke control or other fire protection systems but do not usually sound an audible warning.
Parts of an external wall with less fire resistance than the appropriate amount given in Appendix B, Table B4, are called unprotected areas.
Unprotected areas should not exceed the result given by one of the methods in paragraph 11.16, and the rest of the wall (if any) should be fire resisting but only from the inside of the building.
Provisions for the fire properties of roofs are given in other parts of this document.
a. Requirement B1 – for roofs that are part of a means of escape.
b. Requirement B2 – for the internal surfaces of rooflights as part of internal linings.
c. Requirement B3 – for roofs that are used as a floor and for roofs passing over a compartment wall.
d. Section 11 – the circumstances in which a roof is subject to the provisions for space separation.
Separation distance is the minimum distance from the roof, or part of the roof, to the relevant boundary (paragraph 11.4). Table 12.1 sets out separation distances by the type of roof covering and the size and use of the building.
In addition, roof covering products (and/or materials) defined in Commission Decision 2000/553/ EC of 6 September 2000, implementing Council Directive 89/106/EEC, can be considered to fulfil all of the requirements for the performance characteristic ‘external fire performance’ without the need for testing, provided that any national provisions on the design and execution of works are fulfilled, and can be used without restriction.
Separation distance is the minimum distance from the roof, or part of the roof, to the relevant boundary (paragraph 11.4). Table 12.1 sets out separation distances by the type of roof covering and the size and use of the building.
In addition, roof covering products (and/or materials) defined in Commission Decision 2000/553/ EC of 6 September 2000, implementing Council Directive 89/106/EEC, can be considered to fulfil all of the requirements for the performance characteristic ‘external fire performance’ without the need for testing, provided that any national provisions on the design and execution of works are fulfilled, and can be used without restriction.
Separate guidance applies to means of escape within the flat and within the common parts of the building that lead to a place of safety. Flats at ground level are treated similarly to dwellinghouses. With increasing height, more complex provisions are needed.
Separate guidance applies to means of escape within the flat and within the common parts of the building that lead to a place of safety. Flats at ground level are treated similarly to dwellinghouses. With increasing height, more complex provisions are needed.
The provisions in this section make the following assumptions.
a. Any fire is likely to be in a flat.
b. There is no reliance on external rescue.
c. Simultaneous evacuation of all flats is unlikely to be necessary due to compartmentation.
d. Fires in common parts of the building should not spread beyond the fabric in the immediate vicinity. In some cases, however, communal facilities exist that require additional measures to be taken.
Escape stair lighting should be on a separate circuit from the electricity supply to any other part of the escape route.
Escape stair lighting should be on a separate circuit from the electricity supply to any other part of the escape route.
In mixed use buildings, separate means of escape should be provided from any storeys or parts of storeys used for the ‘residential’ or ‘assembly and recreation’ purpose groups (purpose groups 1, 2 and 5), other than in the case of certain small buildings or buildings in which the residential accommodation is ancillary (see paragraphs 3.76 and 3.77)
In mixed use buildings, separate means of escape should be provided from any storeys or parts of storeys used for the ‘residential’ or ‘assembly and recreation’ purpose groups (purpose groups 1, 2 and 5), other than in the case of certain small buildings or buildings in which the residential accommodation is ancillary (see paragraphs 3.76 and 3.77)
Refuse chutes and rooms for storing refuse should meet both of the following conditions.
a. Be separated from other parts of the building by fire resisting construction (minimum REI 30 in buildings with a top storey up to 5m above ground level; otherwise REI 60).
b. Not be situated within a protected stairway or protected lobby.
Where a common stair is not part of the only escape route from a flat, it may also serve ancillary accommodation from which it is separated by a protected lobby or protected corridor (minimum REI 30).
Where a common stair is not part of the only escape route from a flat, it may also serve ancillary accommodation from which it is separated by a protected lobby or protected corridor (minimum REI 30).
If glazed elements in fire resisting enclosures and doors can only meet the required integrity performance, their use is limited. These limitations depend on whether the enclosure forms part of a protected shaft (see Section 7) and the provisions set out in Appendix B, Table B5. If both integrity and insulation performance can be met, there is no restriction in this document on the use or amount of glass.
Glazed elements should also comply with the following, where necessary.
a. If the enclosure forms part of a protected shaft: Section 7.
b. Appendix B, Table B5.
c. Guidance on the safety of glazing: Approved Document K.
a. DIFFUSER FORMING PART OF CEILING
b. DIFFUSER IN FITTING BELOW AND NOT FORMING PART OF CEILING
See para 4.15
If a garage is attached to or forms an integral part of a dwellinghouse, the garage should be separated from the rest of the dwellinghouse by fire resisting construction (minimum REI 30) (Diagram 5.1).
If a garage is attached to or forms an integral part of a dwellinghouse, the garage should be separated from the rest of the dwellinghouse by fire resisting construction (minimum REI 30) (Diagram 5.1).
If a loadbearing wall is any of the following, guidance in other sections may also apply.
a. A compartment wall (including a wall common to two buildings): Section 7.
b. Enclosing a place of special fire hazard: Section 7.
c. Protecting a means of escape: Sections 2 and 3.
d. An external wall: Sections 10 and 11.
e. Enclosing a firefighting shaft: Section 15.
In a converted building with four or more storeys, the full standard of fire resistance given in Appendix B is necessary.
All of the following should be provided as compartment walls and compartment floors and should have, as a minimum, the fire resistance given in Appendix B, Table B3.
a. Any floor (unless it is within a flat, i.e. between one storey and another within one individual dwelling).
b. Any wall separating a flat from another part of the building.
c. Any wall enclosing a refuse storage chamber.
d. Any wall common to two or more buildings.
Compartment walls not described in paragraphs 7.8 and 7.9 should run the full height of the storey in which they are situated.
At the junction with another compartment wall or an external wall, the fire resistance of the compartmentation should be maintained. Fire-stopping that meets the provisions in paragraphs 9.24 to 9.29 should be provided.
Parts of a building occupied mainly for different purposes should be separated from one another by compartment walls and/or compartment floors. Compartmentation is not needed if one of the different purposes is ancillary to the other. See paragraphs 0.18 and 0.19.
Parts of a building occupied mainly for different purposes should be separated from one another by compartment walls and/or compartment floors. Compartmentation is not needed if one of the different purposes is ancillary to the other. See paragraphs 0.18 and 0.19.
Compartment walls forming a separated part of a building should run the full height of the building in a continuous vertical plane.
Separated parts can be assessed independently to determine the appropriate standard of fire resistance in each. The two separated parts can have different standards of fire resistance.
Compartment walls forming a separated part of a building should run the full height of the building in a continuous vertical plane.
Separated parts can be assessed independently to determine the appropriate standard of fire resistance in each. The two separated parts can have different standards of fire resistance.
If the fire resisting construction of a protected escape route is either of the following.
a. Not carried to full storey height.
b. At the top storey, not carried to the underside of the roof covering.
Then the cavity above or below the fire resisting construction should be either of the following.
i. Fitted with cavity barriers on the line of the enclosure.
ii. For cavities above the fire resisting construction, enclosed on the lower side by a fire resisting ceiling (minimum EI 30) that extends throughout the building, compartment or separated part (see Diagram 8.3).
If air handling ducts pass through fire-separating elements, the fire performance of the elements should be maintained using one or more of the following four methods. In most ductwork systems, a combination of the four methods is best.
a. Method 1 – thermally activated fire dampers.
b. Method 2 – fire resisting enclosures.
c. Method 3 – protection using fire resisting ductwork.
d. Method 4 – automatically activated fire and smoke dampers triggered by smoke detectors.
Where required, sprinkler systems should be provided throughout the building or separated part,
unless acting as a compensatory feature to address a specific risk. They should be designed and
installed in accordance with the following.
a. For residential buildings, the requirements of BS 9251.
b. For non-residential buildings, or residential buildings outside the scope of BS 9251, the
requirements of BS EN 12845, including the relevant hazard classification together with
additional measures to improve system reliability and availability as described in Annex F of the
standard.
NOTE: Any sprinkler system installed to satisfy the requirements of Part B of the Building
Regulations should be provided with additional measures to improve system reliability and
availability and is therefore to be regarded as a life safety system. However, there may be some
circumstances in which additional measures to improve system reliability and availability specified
in Annex F of BS EN 12845 are inappropriate or unnecessary.
Where required, sprinkler systems should be provided throughout the building or separated part,
unless acting as a compensatory feature to address a specific risk. They should be designed and
installed in accordance with the following.
a. For residential buildings, the requirements of BS 9251.
b. For non-residential buildings, or residential buildings outside the scope of BS 9251, the
requirements of BS EN 12845, including the relevant hazard classification together with
additional measures to improve system reliability and availability as described in Annex F of the
standard.
NOTE: Any sprinkler system installed to satisfy the requirements of Part B of the Building
Regulations should be provided with additional measures to improve system reliability and
availability and is therefore to be regarded as a life safety system. However, there may be some
circumstances in which additional measures to improve system reliability and availability specified
in Annex F of BS EN 12845 are inappropriate or unnecessary.
separating floor
Adjoining buildings should only be separated by walls, not floors. Compartment walls common to two or more buildings should comply with both of the following.
a. Run the full height of the building in a continuous vertical plane.
b. Be continued through any roof space to the underside of the roof (see Diagram 5.2).
Parts of a building occupied mainly for different purposes should be separated from one another by compartment walls and/or compartment floors. Compartmentation is not needed if one of the different purposes is ancillary to the other. See paragraphs 0.18 and 0.19.
Adjoining buildings should only be separated by walls, not floors. Compartment walls common to two or more buildings should comply with both of the following.
a. Run the full height of the building in a continuous vertical plane.
b. Be continued through any roof space to the underside of the roof (see Diagram 5.2).
separating wall
NOTES:
For single storey buildings, the periods under the heading ‘Up to 5’ apply. If single storey buildings have basements, for the basement storeys the period appropriate to their depth applies.
* For the floor over a basement or, if there is more than one basement, the floor over the topmost basement, the higher of the period for the basement storey and the period for the ground or upper storey applies.
† For compartment walls that separate buildings, the period is increased to a minimum of 60 minutes.
+ For any floor that does not contribute to the support of the building within a flat of more than one storey, the period is reduced to 30 minutes.
§ For flat conversions, refer to paragraphs 6.5 to 6.7 regarding the acceptability of 30 minutes.
‡ For elements that do not form part of the structural frame, the period is reduced to 90 minutes.
# For elements that protect the means of escape, the period is increased to 30 minutes.
1. Refer to note 1, Table B3 for the specific provisions of test.
2. Blocks of flats with a floor more than 30m above ground level should be fitted with a sprinkler system in accordance with Appendix E.
NOTE:
Sprinklers only need to be provided within the individual flats, they are not required in the common areas such as stairs, corridors or landings when these areas are fire sterile.
3.‘With sprinkler system’ means that the building is fitted throughout with an automatic sprinkler system in accordance with Appendix E.
4. Very large (over 18m in height or with a 10m deep basement) or unusual dwellinghouses are outside the scope of the guidance provided with regard to dwellinghouses.
5. A minimum of 30 minutes in the case of three storey dwellinghouses, increased to 60 minutes minimum for compartment walls separating buildings.
6. Buildings within the ‘office’, ‘shop and commercial’, ‘assembly and recreation’, ‘industrial’ and ‘storage and other non-residential’ (except car parks for light vehicles) purpose groups (purpose groups 3 to 7(a)) require sprinklers where there is a top storey above 30m.
The sprinkler system should be provided in accordance with Appendix E.
7. The car park should comply with the relevant provisions in the guidance on requirement B3, Section 11 of
Approved Document B Volume 2.
8. For the purposes of meeting the Building Regulations, the following types of steel elements are deemed to have satisfied the minimum period of fire resistance of 15 minutes when tested to the European test method.
i. Beams supporting concrete floors, maximum Hp/A=230m-1 operating under full design load.
ii. Free-standing columns, maximum Hp/A=180m-1 operating under full design load.
iii. Wind bracing and struts, maximum Hp/A=210m-1 operating under full design load.
Guidance is also available in BS EN 1993-1-2.
NOTES:
For single storey buildings, the periods under the heading ‘Up to 5’ apply. If single storey buildings have basements, for the basement storeys the period appropriate to their depth applies.
* For the floor over a basement or, if there is more than one basement, the floor over the topmost basement, the higher of the period for the basement storey and the period for the ground or upper storey applies.
† For compartment walls that separate buildings, the period is increased to a minimum of 60 minutes.
+ For any floor that does not contribute to the support of the building within a flat of more than one storey, the period is reduced to 30 minutes.
§ For flat conversions, refer to paragraphs 6.5 to 6.7 regarding the acceptability of 30 minutes.
‡ For elements that do not form part of the structural frame, the period is reduced to 90 minutes.
# For elements that protect the means of escape, the period is increased to 30 minutes.
1. Refer to note 1, Table B3 for the specific provisions of test.
2. Blocks of flats with a floor more than 30m above ground level should be fitted with a sprinkler system in accordance with Appendix E.
NOTE:
Sprinklers only need to be provided within the individual flats, they are not required in the common areas such as stairs, corridors or landings when these areas are fire sterile.
3.‘With sprinkler system’ means that the building is fitted throughout with an automatic sprinkler system in accordance with Appendix E.
4. Very large (over 18m in height or with a 10m deep basement) or unusual dwellinghouses are outside the scope of the guidance provided with regard to dwellinghouses.
5. A minimum of 30 minutes in the case of three storey dwellinghouses, increased to 60 minutes minimum for compartment walls separating buildings.
6. Buildings within the ‘office’, ‘shop and commercial’, ‘assembly and recreation’, ‘industrial’ and ‘storage and other non-residential’ (except car parks for light vehicles) purpose groups (purpose groups 3 to 7(a)) require sprinklers where there is a top storey above 30m.
The sprinkler system should be provided in accordance with Appendix E.
7. The car park should comply with the relevant provisions in the guidance on requirement B3, Section 11 of
Approved Document B Volume 2.
8. For the purposes of meeting the Building Regulations, the following types of steel elements are deemed to have satisfied the minimum period of fire resistance of 15 minutes when tested to the European test method.
i. Beams supporting concrete floors, maximum Hp/A=230m-1 operating under full design load.
ii. Free-standing columns, maximum Hp/A=180m-1 operating under full design load.
iii. Wind bracing and struts, maximum Hp/A=210m-1 operating under full design load.
Guidance is also available in BS EN 1993-1-2.
The unprotected area of the external wall of a stairway forming a protected shaft may be disregarded for separation distance purposes
Roofs pitched at an angle of less than 70 degrees may be disregarded for separation distance purposes
Represents an unprotected area of not more than 1m2 which may consist of two or more smaller areas within an area of 1000mm X 1000mm
Represents an area of not more than 0.1m2
See para 11.11
The unprotected area of the external wall of a stairway forming a protected shaft may be disregarded for separation distance purposes
Roofs pitched at an angle of less than 70 degrees may be disregarded for separation distance purposes
Represents an unprotected area of not more than 1m2 which may consist of two or more smaller areas within an area of 1000mm X 1000mm
Represents an area of not more than 0.1m2
See para 11.11
Adjoining buildings should only be separated by walls, not floors. Compartment walls common to two or more buildings should comply with both of the following.
a. Run the full height of the building in a continuous vertical plane.
b. Be continued through any roof space to the underside of the roof (see Diagram 5.2).
Dwellinghouses that are semi-detached or in terraces should be considered as separate buildings. Every wall separating the dwellinghouses should be constructed as a compartment wall (see paragraphs 5.8 to 5.12).
Dwellinghouses that are semi-detached or in terraces should be considered as separate buildings. Every wall separating the dwellinghouses should be constructed as a compartment wall (see paragraphs 5.8 to 5.12).
Adjoining buildings should only be separated by walls, not floors. Compartment walls common to two or more buildings should comply with both of the following.
a. Run the full height of the building in a continuous vertical plane.
b. Be continued through any roof space to the underside of the roof (see Diagram 5.2).
Compartment walls forming a separated part of a building should run the full height of the building in a continuous vertical plane.
Separated parts can be assessed independently to determine the appropriate standard of fire resistance in each. The two separated parts can have different standards of fire resistance.
Compartment walls forming a separated part of a building should run the full height of the building in a continuous vertical plane.
Separated parts can be assessed independently to determine the appropriate standard of fire resistance in each. The two separated parts can have different standards of fire resistance.
sheltered housing
B3.(1) The building shall be designed and constructed so that, in the event of fire, its stability will be maintained for a reasonable period
(2) A wall common to two or more buildings shall be designed and constructed so that it adequately resists the spread of fire between those buildings.
For the purposes of this sub-paragraph a house in a terrace and a semi-detached house are each to be treated as a separate building.
(3) Where reasonably necessary to inhibit the spread of fire within the building, measures shall be taken, to an extent appropriate to the size and intended use of the building, comprising either or both of the following—
(a) sub-division of the building with fire-resisting construction;
(b) installation of suitable automatic fire suppression systems.
(4) The building shall be designed and constructed so that the unseen spread of fire and smoke within concealed spaces in its structure and fabric is inhibited.
Requirement B3(3) does not apply to material alterations to any prison provided under section 33 of the Prison Act 1952.
Access and facilities for the fire service
B5.(1)The building shall be designed and constructed so as to provide reasonable facilities to assist fire fighters in the protection of life.
(2)Reasonable provision shall be made within the site of the building to enable fire appliances to gain access to the building.
While many of the provisions in this approved document for means of escape from flats are applicable to sheltered housing, the nature of the occupancy may necessitate some additional fire protection measures. The extent of such measures will depend on the form of the development. For example, a group of specially adapted bungalows or two storey flats, with few communal facilities, will not need to be treated differently from other single storey or two storey dwellinghouses or flats.
In sheltered housing, the guidance in Approved Document B Volume 2 should be consulted for the design of communal facilities, such as a common lounge.
The fire safety aspects of the Building Regulations aim to achieve reasonable standards of health and safety for people in and around buildings. People, regardless of ability, age or gender, should be able to access buildings and use their facilities. The fire safety measures incorporated into a building should take account of the needs of everyone who may access the building, both as visitors and as people who live or work in it. It is not appropriate, except in exceptional circumstances, to assume that certain groups of people will be excluded from a building because of its use. The provisions in this approved document are considered to be of a reasonable standard for most buildings. However, some people’s specific needs might not be addressed. In some situations, additional measures may be needed to accommodate these needs. This should be done on a case- by-case basis.
These provisions do not apply to the following.
a. The common parts of a sheltered housing development, such as communal lounges.
b. Sheltered accommodation in the 'residential (institutional)' or 'residential (other)' purpose groups (purpose group 2(a) or 2(b)).
In these parts, means of warning should follow the guidance for buildings other than dwellings in Volume 2 of Approved Document B.
Regulation 7(2) applies to any building with a storey at least 18m above ground level (as
measured in accordance with Diagram D6 in Appendix D) and which contains one or more
dwellings; an institution; or a room for residential purposes. It requires that all materials which become part of an external wall or specified attachment achieve class A2-s1, d0 or class A1 in accordance with BS EN 13501-1, other than those exempted by regulation 7(3).
NOTE: The above includes student accommodation, care homes, sheltered housing, hospitals, dormitories in boarding schools, hotels, hostels and boarding houses. See regulation 7(4) for the definition of relevant buildings.
NOTE: Transposition to national class (Table B1) does not apply to the classification in this paragraph.
NOTES:
1. If travel distance is measured to a stair lobby, the lobby must not provide direct access to any storage room, flat or other space containing a fire hazard.
2. In the case of a small single stair building in accordance with Diagram 3.9, this is reduced to 4.5m.
3. Does not apply if all flats on a storey have independent alternative means of escape.
4. Sheltered housing may require reduced maximum travel distances.
should
NOTES:
1. As an alternative to using the values in the table, the floor space factor may be determined by reference to actual data taken from similar premises. Where appropriate, the data should reflect the average occupant density at a peak trading time of year.
2. Where accommodation is not directly covered by the descriptions given, a reasonable value based on a similar use may be selected.
3. Where any part of the building is to be used for more than one type of accommodation, the most onerous factor(s) should be applied. Where the building contains different types of accommodation, the occupancy of each different area should be calculated using the relevant space factor.
4. For detailed guidance on appropriate floor space factors for concourses in sports grounds refer to Concourses published by the Football Licensing Authority.
5. Alternatively the occupant number may be taken as the number of fixed seats provided, if the occupants will normally be seated.
6. Shops excluding those under item 10, but including: supermarkets and department stores (main sales areas), shops for personal services, such as hairdressing, and shops for the delivery or collection of goods for cleaning, repair or other treatment or for members of the public themselves carrying out such cleaning, repair or other treatment.
7. Shops (excluding those in covered shopping complexes but including department stores) trading predominantly in furniture, floor coverings, cycles, prams, large domestic appliances or other bulky goods, or trading on a wholesale self-selection basis (cash and carry).
Where there are multiple main uses that are not ancillary to one another (for example, shops with independent offices above), each use should be assigned to a purpose group in its own right.
Where there is doubt as to which purpose group is appropriate, the more onerous guidance should be applied.
In sheltered housing, the guidance in Approved Document B Volume 2 should be consulted for the design of communal facilities, such as a common lounge.
Guidance is given on each aspect separately, though many are closely interlinked. The document should be considered as a whole. The relationship between different requirements and their interdependency should be recognised. Particular attention should be given to the situation where one part of the guidance is not fully followed, as this could have a negative effect on other provisions.
The fire safety aspects of the Building Regulations aim to achieve reasonable standards of health and safety for people in and around buildings. People, regardless of ability, age or gender, should be able to access buildings and use their facilities. The fire safety measures incorporated into a building should take account of the needs of everyone who may access the building, both as visitors and as people who live or work in it. It is not appropriate, except in exceptional circumstances, to assume that certain groups of people will be excluded from a building because of its use. The provisions in this approved document are considered to be of a reasonable standard for most buildings. However, some people’s specific needs might not be addressed. In some situations, additional measures may be needed to accommodate these needs. This should be done on a case- by-case basis.
All dwellings should have a fire detection and alarm system, minimum Grade D2 Category LD3
standard, in accordance with the relevant recommendations of BS 5839-6.
A higher standard of protection should be considered where occupants of a proposed dwelling
would be at special risk from fire. Further advice on this is also given in BS 5839-6.
In student residences that are designed and occupied as a block of flats, separate automatic detection should be provided in each self-contained flat where all of the following apply.
a. A group of up to six students shares the flat.
b. Each flat has its own entrance door.
c. The compartmentation principles for flats in Section 7 have been followed.
Where a total evacuation strategy is adopted, the alarm system should follow the guidance for buildings other than dwellings in Volume 2 of Approved Document B.
The fire detection and alarm systems in flats should connect to a central monitoring point or alarm
receiving centre. The systems should alert the warden or supervisor and identify the individual flat
where a fire has been detected.
Fire detection and alarm systems sometimes trigger other systems. The interface between systems
must be reliable. Particular care should be taken if the interface is facilitated via another system.
Where any part of BS 7273 applies to the triggering of other systems, the recommendations of that
part of BS 7273 should be followed.
Smoke alarms should be mains operated and conform to BS EN 14604.
Heat alarms should be mains operated and conform to BS 5446-2.
A large dwellinghouse of two storeys (excluding basement storeys) should be fitted with a Grade A
Category LD3 fire detection and alarm system, as described in BS 5839-6.
A large dwellinghouse of three or more storeys (excluding basement storeys) should be fitted with
a Grade A Category LD2 fire detection and alarm system as described in BS 5839-6.
Smoke alarms should be provided in the circulation spaces of the dwelling in accordance with paragraphs 1.1 to 1.4.
In buildings that include a ‘residential’ purpose (purpose groups 1 and 2) with a storey 11m or more in height (see Diagram D6 in Appendix D) balconies should meet either of the following conditions.
a. Only contain materials achieving class A1 or A2-s1, d0, except for any of the following.
i. Cavity trays when used between two leaves of masonry.
ii. Intumescent and fire-stopping materials where the inclusion of the materials is necessary to meet the requirements of Part B of Schedule 1 to the Building Regulations 2010.
iii. Membranes.
iv. Seals, gaskets, fixings, sealants and backer rods.
v. Thermal break materials where the inclusion of the materials is necessary to meet the thermal bridging requirements of Part L of Schedule 1 to the Building Regulations 2010.
vi. Any material achieving class A1fl or A2fl-s1 when it forms the top horizontal floor layer of a balcony and is provided with an imperforate substrate under it which extends to the full size of the class A1fl or A2fl-s1 material.
vii. Electrical installations.
viii. Fibre optic cables.
b. Achieve both of the following conditions.
Have an imperforate soffit which extends to the full area of the balcony, achieves a minimum REI 30 rating and is constructed of materials achieving class A2-s1, d0 or better.
ii. Materials achieving class B-s1, d0 or worse extending beyond the boundary of a single
compartment should include a band of material rated class A2-s1, d0 or better, a minimum of 300mm in width centred on that boundary line.
Where regulation 7(2) applies, that regulation prevails over all the provisions in this paragraph.
Particular attention is drawn to the following points.
a. Membranes used as part of the external wall construction above ground level should achieve a minimum of class B-s3, d0. Roofing membranes do not need to achieve a minimum of class A2-s1, d0 when used as part of a roof connecting to an external wall.
b. Internal linings should comply with the guidance provided in Section 4.
c. Any part of a roof should achieve the minimum performance as detailed in Section 12.
d. As per regulation 7(3), window frames and glass (including laminated glass) are exempted
from regulation 7(2). Window spandrel panels and infill panels must comply with regulation 7(2).
e. Thermal breaks are small elements used as part of the external wall construction to restrict
thermal bridging. There is no minimum performance for these materials. However, they
should not span two compartments and should be limited in size to the minimum required
to restrict the thermal bridging (the principal insulation layer is not to be regarded as a
thermal break).
f. Regulation 7(2) only applies to specified attachments. Shop front signs and similar attachments are
not covered by the requirements of regulation 7(2), although attention is drawn to paragraph 10.21g.
g. While regulation 7(2) applies to materials which become part of an external wall or specified
attachment, consideration should be given to other attachments to the wall which could
impact on the risk of fire spread over the wall.
h. Any material achieving class A1fl or A2fl-s1 in accordance with BS EN 13501-1 is exempted when it
meets both of the following conditions.
i. It forms the top horizontal floor layer of a balcony.
ii. It is provided with an imperforate substrate under it which extends to the full size of the
class A1fl or A2fl-s1 material.
Cavity barriers should be provided in accordance with Section 5 in dwellinghouses and Section 8 in flats.
This boundary coincides with and is therefore relevant to side A
The boundary is parallel to side B2
But the relevant boundary may be the centre line of a road, railway, canal or river
NOTES:
This boundary is at less than 80 degrees to side C and is therefore relevant to side C
This diagram sets out the rules that apply in respect of a boundary for it to be considered as a relevant boundary.
For a boundary to be relevant it should comply with one of the following:
a. Coincide with the side of the building (A).
b. Be parallel to the side of the building (B1 or B2).
c. Be at an angle of maximum 80 degrees to the side of the building (C).
This boundary is parallel to and therefore relevant to side B1
See para 11.5
If a reduced separation distance between buildings, or increased amount of unprotected area, is required, smaller compartments should be considered.
NOTES:
The notional boundary should be set in the area between the two buildings using the following rules:
1. The notional boundary is assumed to exist in the space between the buildings and is positioned so that one of the buildings would comply with the provisions for space separation having regard to the amount of its unprotected area. In practice, if one of the buildings is existing, the position of the boundary will be set by the space separation factors for that building.
2. The siting of the new building, or the second building if both are new, can then be checked to see that it also complies, using the notional boundary as the relevant boundary for the second building.
Notional boundary
Site boundary
Compliance with the provisions for space separation in respect of building A
Compliance with the provisions for space separation in respect of building B
See para 11.5
Where a fire resisting external wall has an external surface material that is worse than class B-s3, d2 and is more than 1mm thick, that part of the wall should be classified as an unprotected area equating to half its area (Diagram 11.4).
Unprotected areas should meet the conditions in Diagram 11.5, and the rest of the wall should be fire resisting from both sides.
External surface materials facing the boundary should be class B-s3, d2 or better.
Unprotected areas should not exceed the result given by one of the methods in paragraph 11.16, and the rest of the wall (if any) should be fire resisting but only from the inside of the building.
NOTES:
1.There are restrictions on the use of plastic rooflights in the guidance to requirement B2 in Section 4.
2.Surrounding roof covering to be a material of class A2-s3, d3 or better for at least 3m distance.
3.Where Diagram 5.2a or 5.2b applies, rooflights should be at least 1500mm from the compartment wall.
See paras 12.5 and 12.6
NOTES:
None of the above designations are suitable for protected stairways.
Polycarbonate and uPVC rooflights that achieve a class C-s3, d2 rating by test (see paragraph 12.7) may be regarded as having a BROOF(t4) classification.
Where Diagram 5.2a or 5.2b applies, rooflights should be a minimum of 1500mm from the compartment wall.
If double-skinned or laminate products have upper and lower surfaces of different materials, the greater distance applies.
1. See also the guidance to requirement B2 in Section 4.
2. The designation of external roof surfaces is explained in Appendix B.
3. Single-skinned rooflight only, in the case of non-thermoplastic material.
4. The rooflight should also meet the provisions of Diagram 12.1.
NOTES:
None of the above designations are suitable for protected stairways.
Polycarbonate and uPVC rooflights that achieve a class C-s3, d2 rating by test (paragraph 12.7) may be regarded as having a BROOF(t4) classification.
Where Diagram 5.2a or 5.2b applies, rooflights should be a minimum of 1500mm from the compartment wall.
If double-skinned or laminate products have upper and lower surfaces of different materials, the greater distance applies.
1. See also the guidance to requirement B2 in section 4.
2. No limit in the case of any space described in 2a, b and c.
3. Single-skinned rooflight only, in the case of non-thermoplastic material.
4. The rooflight should also meet the provisions of diagram 12.1.
For dwellinghouses, access for a pumping appliance should be provided to within 45m of all points inside the dwellinghouse. Every elevation to which vehicle access is provided should have a suitable door(s), not less than 750mm wide, giving access to the interior of the building.
For flats, either of the following provisions should be made.
a. Provide access for a pumping appliance to within 45m of all points inside each flat of a block, measured along the route of the hose. Every elevation to which vehicle access is provided should have a suitable door(s), not less than 750mm wide, giving access to the interior of the building. Door(s) should be provided such that there is no more than 60m between each door and/or the end of that elevation (e.g. a 150m elevation would need at least two doors).
b. Provide fire mains in accordance with paragraphs 13.5 and 13.6.
Access routes and hardstandings should comply with the guidance in Table 13.1.
Dead-end access routes longer than 20m require turning facilities, as in Diagram 13.1. Turning facilities should comply with the guidance in Table 13.1.
For buildings fitted with dry fire mains, both of the following apply.
a. Access should be provided for a pumping appliance to within 18m of each fire main inlet connection point. Inlets should be on the face of the building.
b. The fire main inlet connection point should be visible from the parking position of the appliance, and meet the provisions in Section 8 of BS 9990.
For buildings fitted with wet fire mains, access for a pumping appliance should comply with both of the following.
a. Within 18m, and within sight, of an entrance giving access to the fire main.
b. Within sight of the inlet to replenish the suction tank for the fire main in an emergency.
Fire mains are installed for the fire and rescue service to connect hoses for water. They may be either of the following.
a. The ‘dry’ type, which are both of the following.
i. Normally kept empty.
ii. Supplied through a hose from a fire and rescue service pumping appliance.
b. The ‘wet’ type, which are both of the following.
i. Kept full of water.
ii. Supplied by pumps from tanks in the building.
There should be a facility to replenish a wet system from a pumping appliance in an emergency.
Each fire hydrant should be clearly indicated by a plate, fixed nearby in a conspicuous position, in accordance with BS 3251.
The alternative source of water supply should be one of the following, subject to consultation with the local fire and rescue service.
a. A charged static water tank with a minimum capacity of 45,000 litres.
b. A spring, river, canal or pond that is capable of fulfilling both of the following conditions.
i. Providing or storing a minimum of 45,000 litres of water at all times.
ii. Providing access, space and a hardstanding for a pumping appliance.
c. Any other water supply that the local fire and rescue service considers appropriate.
Buildings without firefighting shafts should be provided with fire mains where fire service vehicle access is not provided in accordance with paragraph 13.2(a). In these cases, the fire mains should be located within the protected stairway enclosure, with a maximum hose distance of 45m from the fire main outlet to the furthest point inside each flat, measured on a route suitable for laying a hose.
The outlets from fire mains should be located within the protected stairway enclosure (see Diagram 15.1).
Fire service vehicle access to fire mains should be provided as described in paragraphs 13.5 and 13.6.
If additional hydrants are required, these should be provided in accordance with the following.
a. For buildings provided with fire mains – within 90m of dry fire main inlets.
b. For buildings not provided with fire mains – hydrants should be both of the following.
i. Within 90m of an entrance to the building.
ii. A maximum of 90m apart.
Minimum fire resistance REI60 from both sides with E30 Sa fire doors
Minimum fire resistance REI 120 from accommodation side and REI60 from inside the shaft with E60 Sa fire doors
NOTES:
1.Outlets from a fire main should be located in the firefighting lobby or, in the case of a shaft serving flats, in the firefighting stairway (see Diagram b).
2.Smoke control should be provided in accordance with BS9999 or, where the firefighting shaft only serves flats, the provisions for smoke control given in paragraph 3.49 may be followed instead.
3.A firefighting lift is required if the building has a floor more than 18m above, or more than 10m below, fire service vehicle access level.
4.This diagram is only to illustrate the basic components and is not meant to represent the only acceptable layout. The firefighting shaft should be constructed generally in accordance with section 6 of BS 9999.
5.For the minimum fire resistance of lift doors see Table C1.
See paras 15.2,15.8 and 15.9
All firefighting shafts should have fire mains with outlet connections and valves at every storey.
The fire and rescue service should be able to manually open and close rolling shutters without the use of a ladder.
To assist the fire service to identify each floor in a block of flats with a top storey more than 11m above ground level (see Diagram D6), floor identification signs and flat indicator signs should be provided.
In blocks of flats (purpose group 1(a)) with a top storey over 18m above ground level (see Diagram D6 in Appendix D) an evacuation alert system should be provided in accordance with BS 8629.
Blocks of flats (purpose group 1(a)) with a top storey more than 11m above ground level (see Diagram D6 in Appendix D) should be provided with a secure information box.
NOTE: Consideration should also be given to other buildings with large, complex or uncommon layouts where the provision of a secure information box may be beneficial.
A building with a storey more than 18m above the fire and rescue service vehicle access level should have one or more firefighting shafts, each containing a firefighting lift (Diagram 15.1). The number and location of firefighting shafts should comply with paragraphs 15.4 to 15.7. Firefighting shafts are not required to serve a basement that is not large or deep enough to need one (see paragraph 15.3 and Diagram 15.2).
Buildings in which firefighting shafts should be provided,
showing which storeys need to be served >18m >10m
a. Any building The upper storeys in any building with a storey more than 18m above fire service vehicle access level
b. Any building The basement storeys in any building with a basement more than 10m below fire service vehicle access level
c. Any building The basement storey(s) in any building with two or more basements each exceeding 900m2
Fire service vehicle access level
Two or more basement storeys each exceeding 900m2
Extent of firefighting Extent of firefighting lift stair
NOTES:
1.Height excludes any top storey(s) consisting exclusively of plant rooms.
2.Firefighting shafts should serve all floors through which they pass.
See para 15.2
A building with basement storeys should have firefighting shafts in accordance with the following.
a. There is a basement more than 10m below the fire and rescue service vehicle access level. The firefighting shafts should contain firefighting lifts.
b. There are two or more basement storeys, each with a minimum area of 900m2. The firefighting shafts do not need to include firefighting lifts.
The building’s height and size determine whether firefighting shafts also serve upper storeys.
NOTES:
1.Hose laying distance should be measured from the fire main outlet along the route suitable for laying hose. If this route is not known, the distance should be taken at two-thirds of the direct distance
2.The fire main outlet should be located according to Section 14.
See para 15.7
Firefighting shafts should serve all storeys through which they pass.
Firefighting shafts and protected stairways should be positioned such that every part of each storey more than 18m above the fire and rescue service vehicle access level complies with the maximum distances given in paragraph 15.7. Distances should be measured from the fire main outlet on a route suitable for laying a hose.
NOTE: If the internal layout is not known, the distance should be measured at two-thirds of the direct distance.
In any building, the hose laying distance should meet all of the following conditions.
a. A maximum of 60m from the fire main outlet in a firefighting shaft (see Diagram 15.3).
b. Additionally, where sprinklers have not been provided in accordance with Appendix E, the hose laying distance should be a maximum of 45m from a fire main outlet in a protected stairway (although this does not imply that the protected stairway needs to be designed as a firefighting shaft (see Diagram 15.3)).
Firefighting stairs and firefighting lifts should be approached from either of the following.
a. A firefighting lobby.
b. A protected corridor or protected lobby that complies with the following guidance.
i. Means of escape (Section 3).
ii. Compartmentation (Section 7).
Both the stair and lobby of the firefighting shaft should be provided with a means of venting smoke and heat (see clause 27.1 of BS 9999).
Only services associated with the firefighting shaft, such as ventilation systems and lighting for the firefighting shafts, should pass through or be contained within the firefighting shaft.
Doors of a firefighting lift landing should be a maximum of 7.5m from the door to the firefighting stair (Diagram 15.1).
Firefighting shafts should achieve a minimum fire resistance of REI 120. A minimum of REI 60 is acceptable for either of the following (see Diagram 15.1).
a. Constructions separating the firefighting shaft from the rest of the building.
b. Constructions separating the firefighting stair, firefighting lift shaft and firefighting lobby.
Outlets should not be placed where they prevent the use of escape routes from the building.
The air extraction system should comply with all of the following.
a. It should give at least 10 air changes per hour.
b. It should be capable of handling gas temperatures of 300°C for not less than one hour.
c. It should do either of the following.
i. Be activated automatically if the sprinkler system activates.
ii. Be activated by an automatic fire detection system that conforms to BS 5839-1 (minimum L3 standard).
Further information on equipment for removing hot smoke is given in BS EN 12101-3.
Outlet ducts or shafts, including any bulkheads over them (see Diagram 16.1), should be enclosed in construction of class A1 rating and fire resistance at least equal to that of the element through which they pass.
Each basement space should have one or more smoke outlets.
Where this is not practicable (for example, the plan area is deep and the amount of external wall is restricted by adjoining buildings), the perimeter basement spaces may be vented, with other spaces vented indirectly by opening connecting doors. This does not apply for places of special fire hazard (see paragraph 16.7).
If a basement is compartmented, each compartment should have one or more smoke outlets, rather than indirect venting.
A basement storey or compartment containing rooms with doors or windows does not need smoke outlets.
Smoke outlets should be both of the following.
a. Sited at high level in either the ceiling or wall of the space they serve.
b. Evenly distributed around the perimeter, to discharge to the open air.
The combined clear cross-sectional area of all smoke outlets should be a minimum of 1/40 of the area of the floor of the storey they serve.
Separate outlets should be provided from places of special fire hazard.
If the smoke outlet terminates at a point that is not readily accessible, it should be kept unobstructed and covered only with a class A1 grille or louvre.
If the smoke outlet terminates in a readily accessible position, it may be covered by a panel, stallboard or pavement light that can be broken out or opened. The position of covered smoke outlets should be suitably indicated.
This section is a guide to the information that should be provided. Guidance is in terms of essential information and additional information for complex buildings; however, the level of detail required should be considered on a case-by-case basis.
A detailed record should be provided of both of the following.
a. The fire safety strategy.
b. Procedures for operating and maintaining any fire protection measures. This should include an outline cause and effect matrix/strategy for the building.
Further guidance is available in clause 9 and Annex H of BS 9999.
A detailed record should be provided of both of the following.
b. Procedures for operating and maintaining any fire protection measures. This should include an outline cause and effect matrix/strategy for the building.
Further guidance is available in clause 9 and Annex H of BS 9999.
Windows or external doors providing emergency escape should comply with all of the following.
a. Windows should have an unobstructed openable area that complies with all of the following.
i. A minimum area of 0.33m2.
ii. A minimum height of 450mm and a minimum width of 450mm (the route through the window may be at an angle rather than straight through).
iii. The bottom of the openable area is a maximum of 1100mm above the floor.
b. People escaping should be able to reach a place free from danger from fire. Courtyards or inaccessible back gardens should comply with Diagram 2.5.
c. Locks (with or without removable keys) and opening stays (with child-resistant release catches) may be fitted to escape windows.
d. Windows should be capable of remaining open without being held.
Where a flat roof forms part of a means of escape, it should comply with all of the following.
a. It should be part of the same building from which escape is being made.
b. The route across the roof should lead to a storey exit or external escape route.
c. The part of the roof (including its supporting structure) forming the escape route, and any opening within 3m of the escape route, should be of fire resisting construction (minimum REI 30).
A gallery should comply with one of the following.
a. It should be provided with an alternative exit.
b. It should be provided with an emergency escape window, as described in paragraph 2.10, where the gallery floor is a maximum of 4.5m above ground level.
c. It should meet all the conditions shown in Diagram 2.6.
Any external escape stair should meet all of the following conditions (Diagram 2.7).
a. Doors to the stair should be fire resisting (minimum E 30), except for a single exit door from the building to the top landing of a downward-leading external stair.
b. Fire resisting construction (minimum RE 30) is required for the building envelope within the following zones, measured from the flights and landings of the external stair.
i. 1800mm horizontally.
ii. 9m vertically below.
iii. 1100mm above the top landing of the stair (except where the stair leads from basement to ground level).
c. Fire resisting construction (minimum RE 30) should be provided for any part of the building (including doors) within 1800mm of the escape route from the foot of the stair to a place of safety. This does not apply if there are alternative escape routes from the foot of the external escape stair.
d. Stairs more than 6m in height should be protected from adverse weather. Protection should prevent the build-up of snow or ice but does not require full enclosure.
e. Glazing in areas of fire resisting construction should be fixed shut and fire resisting (in terms of integrity, but not insulation) (minimum E 30).
Work should comply with Parts K and L of Schedule 1 to the Building Regulations. When complete, the building should comply with other applicable parts of Schedule 1 to at least the same level as before.
Where an existing window would be an escape window in a new dwellinghouse, and is big enough to be used for escape purposes, then the replacement should comply with one of the following.
a. The replacement window should be sized to provide at least the same potential for escape.
b. If the existing window was larger than required for escape purposes, the opening can be reduced to the minimum described in paragraph 2.10.
Where a new storey is added through conversion to create a storey above 4.5m, both of the following should apply.
a. The full extent of the escape route should be addressed.
b. Fire resisting doors (minimum E 20) and partitions (minimum REI 30) should be provided, including upgrading the existing doors where necessary.
NOTE: Where the layout is open plan, new partitions should be provided to enclose the escape route (Diagram 2.2).
Where it is undesirable to replace existing doors because of historical or architectural merit, the possibility of retaining, and where necessary upgrading, them should be investigated.
An alternative approach to that described in paragraph 2.21 would be to comply with all of the following.
a. Provide sprinkler protection to the open-plan areas.
b. Provide a fire resisting partition (minimum REI 30) and door (minimum E 20) to separate the ground storey from the upper storeys. The door should allow occupants of the loft room access to a first storey escape window.
c. Separate cooking facilities from the open-plan area with fire resisting construction (minimum REI 30).
Two rooms may be served by a single window. A door between the rooms should provide access to the window without passing through the stair enclosure. Both rooms should have their own access to the internal stair.
Dwellinghouses with one internal stair should comply with paragraphs 2.5 and 2.6. In dwellinghouses with more than one stair, the stairs should provide effective alternative means of escape. The stairs should be physically separated by either of the following.
a. Fire resisting construction (minimum REI 30).
b. More than one room.
Where escape from a dwellinghouse is to an enclosed space with exit only possible through other buildings (e.g. a courtyard or back garden), the length of the space should exceed whichever is the greater of the following.
a. The height of the dwellinghouse above ground level (x).
b. Where a rear extension is provided, the height of the extension (y).
See para 2.10
See Diagram 2.1d. In addition to meeting the provisions in paragraph 2.5, the dwellinghouse should comply with either of the following.
a. Provide an alternative escape route from each storey more than 7.5m above ground level. At the first storey above 7.5m, the protected stairway should be separated from the lower storeys by fire resisting construction (minimum REI 30) if the alternative escape route is accessed via either of the following.
i. The protected stairway to an upper storey.
ii. A landing within the protected stairway enclosure to an alternative escape route on the same storey. The protected stairway at or about 7.5m above ground level should be separated from the lower storeys or levels by fire resisting construction (see Diagram 2.4).
b. Provide a sprinkler system throughout, designed and installed in accordance with BS 9251.
A passenger lift serving any storey more than 4.5m above ground level should be in either of the following.
a. The enclosure to the protected stairway, as described in paragraph 2.5.
b. A fire resisting lift shaft (minimum REI 30).
Air circulation systems which circulate air within an individual dwellinghouse with a floor more than
4.5m above ground level should meet the guidance given in paragraph 2.9.
All of the following precautions should be taken to avoid the spread of smoke and fire to the protected stairway.
a. Transfer grilles should not be fitted in any wall, door, floor or ceiling of the stair enclosure.
b. Any duct passing through the stair enclosure should be rigid steel. Joints between the ductwork and stair enclosure should be fire-stopped.
c. Ventilation ducts supplying or extracting air directly to or from a protected stairway should not serve other areas as well.
d. Any system of mechanical ventilation which recirculates air and which serves both the stair and other areas should be designed to shut down on the detection of smoke within the system.
e. For ducted warm air heating systems, a room thermostat should be sited in the living room. It should be mounted at a height between 1370mm and 1830mm above the floor. The maximum setting should be 27°C.
NOTE: Ventilation ducts passing through compartment walls should comply with the guidance in Section 9.
Where a flat roof forms part of a means of escape, it should comply with all of the following.
a. It should be part of the same building from which escape is being made.
b. The route across the roof should lead to a storey exit or external escape route.
c. The part of the roof (including its supporting structure) forming the escape route, and any opening within 3m of the escape route, should be of fire resisting construction (minimum REI 30).
People should be able to rapidly leave the area around the building. Direct access to a street, passageway, walkway or open space should be available. The route away from the building should comply with the following.
a. Be well defined.
b. If necessary, have suitable guarding.
Final exits should not present a barrier for disabled people. Where the route to a final exit does not include stairs, a level threshold and, where necessary, a ramp should be provided.
For flats more than 4.5m above ground level, a balcony outside an alternative exit should be a common balcony meeting the conditions described in paragraph 3.22.
A gallery should comply with one of the following.
a. It should be provided with an alternative exit.
b. It should be provided with an emergency escape window, as described in paragraph 3.6, where the gallery floor is a maximum of 4.5m above ground level.
c. It should meet the conditions shown in Diagram 3.1.
All habitable rooms (excluding kitchens) should have either of the following.
a. An emergency escape window or external door, as described in paragraph 3.6.
b. In multi-storey flats, direct access to a protected internal stairway (minimum REI 30) leading to an exit from the flat.
Two rooms may be served by a single escape window. A door between rooms should provide access to the escape window without passing through the stair enclosure. Both rooms should have their own access to the internal stair.
One of the following approaches should be adopted, observing the inner room restrictions described in paragraphs 3.7 and 3.8.
a. Provide a protected entrance hall (minimum REI 30) serving all habitable rooms that meets the conditions shown in Diagram 3.2.
b. Plan the flat to meet the conditions shown in Diagram 3.3, so that both of the following apply.
i. The travel distance from the flat entrance door to any point in any habitable room is a maximum of 9m.
ii. Cooking facilities are remote from the main entrance door and do not impede the escape route from anywhere in the flat.
c. Provide an alternative exit from the flat complying with paragraph 3.19.
Where access from any habitable room to the entrance hall or flat entrance is impossible without passing through another room, all of the following conditions should be met (Diagram 3.4).
a. Bedrooms should be separated from living accommodation by fire resisting construction (minimum REI 30) and fire doorsets (minimum E 20).
b. The alternative exit should be in the part of the flat that contains the bedrooms.
A multi-storey flat with an independent external entrance at ground level is similar to a dwellinghouse and means of escape should be planned on the basis of Section 2, depending on the height of the top storey above ground level.
Any alternative exit from a flat should comply with all of the following.
a. It should be remote from the main entrance door to the flat.
b. It should lead to a final exit, via a common stair if necessary, through one of the following.
i. A door to an access corridor, access lobby or common balcony.
ii. An internal private stair leading to an access corridor, access lobby or common balcony at another level.
iii. A door to a common stair.
iv. A door to an external stair.
v. A door to an escape route over a flat roof.
Any access route leading to a final exit or common stair should comply with the provisions for means of escape in the common parts of a flat (see paragraph 3.25).
For systems circulating air only within an individual flat, take all of the following precautions.
a. Transfer grilles should not be fitted in any wall, door, floor or ceiling of the enclosure.
b. Any duct passing through the enclosure should be rigid steel. Joints between the ductwork and enclosure should be fire-stopped.
c. Ventilation ducts serving the enclosure should not serve any other areas.
d. Any system of mechanical ventilation which recirculates air and which serves both the stair and other areas should be designed to shut down on the detection of smoke within the system.
e. For ducted warm air heating systems, a room thermostat should be sited in the living room. It should be mounted at a height between 1370mm and 1830mm above the floor. The maximum setting should be 27°C.
NOTE: Ventilation ducts passing through compartment walls should comply with the guidance in Section 9.
A person escaping through the common area, if confronted by the effects of a fire in another flat, should be able to turn away from it and make a safe escape via an alternative route.
Where a storey or part of a building has multiple escape routes available, one may be over a flat roof that complies with all of the following.
a. It should be part of the same building from which escape is being made.
b. The route across the roof should lead to a storey exit or external escape route.
c. The part of the roof (including its supporting structure) forming the escape route, and any opening within 3m of the escape route, should be of fire resisting construction (minimum REI 30).
d. The route should be clearly defined and guarded by walls and/or protective barriers to protect against falling.
Where a storey or part of a building has multiple escape routes available, one may be over a flat roof that complies with all of the following.
d. The route should be clearly defined and guarded by walls and/or protective barriers to protect against falling.
Escape route travel distances should comply with Table 3.1.
An escape route should not pass through one stair enclosure to reach another. It may pass through a protected lobby (minimum REI 30) of one stair to reach another.
Common corridors should be protected corridors. The wall between each flat and the corridor should be a compartment wall (minimum REI 30 where the top storey is up to 5m above ground level, otherwise REI 60).
Divide a common corridor connecting two or more storey exits with a fire doorset fitted with a self-closing device (minimum E 30 Sa). See Diagram 3.8. Associated screens should be fire resisting. Site doors so that smoke does not affect access to more than one stair.
A fire doorset (minimum E 30 Sa) fitted with a self-closing device (and fire resisting screen, where required) should separate the dead-end portion of a common corridor from the rest of the corridor (Diagrams 3.7a, 3.8b and 3.8c).
Ancillary accommodation should not be located in, or entered from, a protected lobby or protected corridor forming the only common escape route on that storey.
A ramp forming part of an escape route should meet the provisions in Approved Document M. Any sloping floor or tier should have a pitch of not more than 35 degrees to the horizontal.
Except for two storey blocks of flats, all escape routes should have adequate artificial lighting. If the mains electricity power supply fails, escape lighting should illuminate the route (including external escape routes).
Escape stair lighting should be on a separate circuit from the electricity supply to any other part of the escape route.
Escape lighting should conform to BS 5266-1.
To limit potential damage to cables in protected circuits, all of the following should apply.
a. Cables should be sufficiently robust.
b. Cable routes should be carefully selected and/or physically protected in areas where cables may be exposed to damage.
c. Methods of cable support should be class A1 rated and offer at least the same integrity as the cable. They should maintain circuit integrity and hold cables in place when exposed to fire.
A protected circuit to operate equipment during a fire should achieve all of the following.
a. Cables should achieve PH 30 classification when tested in accordance with BS EN 50200 (incorporating Annex E) or an equivalent standard.
b. It should only pass through parts of the building in which the fire risk is negligible.
c. It should be separate from any circuit provided for another purpose.
In mixed use buildings, separate means of escape should be provided from any storeys or parts of storeys used for the ‘residential’ or ‘assembly and recreation’ purpose groups (purpose groups 1, 2 and 5), other than in the case of certain small buildings or buildings in which the residential accommodation is ancillary (see paragraphs 3.76 and 3.77)
Except in buildings that comply with Diagram 3.9, the corridor or lobby next to each stair should have a smoke vent. The location of the vent should comply with both of the following.
a. Be as high as practicable.
b. Be positioned so the top edge is at least as high as the top of the door to the stair.
Smoke vents should comply with one of the following.
a. They should be located on an external wall with minimum free area of 1.5m2.
b. They should discharge into a vertical smoke shaft, closed at the base, that meets all of the following criteria.
i. The shaft should conform to the following conditions.
• Have a minimum cross-sectional area of 1.5m2 (minimum dimension 0.85m in any direction).
• Open at roof level, minimum 0.5m above any surrounding structures within 2m of it horizontally.
• Extend a minimum of 2.5m above the ceiling of the highest storey served by the shaft.
ii. The free area of all the following vents should be a minimum of 1m2 in the following places.
• From the corridor or lobby into the shaft.
• At the opening at the head of the shaft.
• At all internal locations within the shaft (e.g. safety grilles).
iii. The smoke shaft should be constructed from a class A1 material. All vents should either be a smoke leakage (Sa) rated fire doorset (see Appendix C, Table C1, item 2.e for minimum fire resistance) or fitted with a smoke control damper achieving the same period of fire resistance and designed to operate as described below. The shaft should be vertical from base to head, with a maximum of 4m at a maximum inclined angle of 30 degrees.
iv. If smoke is detected in the common corridor or lobby, both of the following should occur.
• Simultaneous opening of vents on the storey where the fire is located, at the top of the smoke shaft and to the stair.
• Vents from the corridors or lobbies on all other storeys should remain closed, even if smoke is subsequently detected on storeys other than where the fire is located.
A vent to the outside with a minimum free area of 1m2 should be provided from the top storey of the stair.
In single stair buildings, smoke vents on the storey where the fire is initiated, and the vent at the head of the stair, should be activated by smoke detectors in the common parts.
In buildings with more than one stair, smoke vents may be activated manually. The control system should open the vent at the head of the stair before, or at the same time as, the vent on the storey where the fire is located. Smoke detection is not required for ventilation purposes in this instance.
Refuse storage chambers, refuse chutes and refuse hoppers should be sited and constructed in accordance with BS 5906.
Refuse chutes and rooms for storing refuse should meet both of the following conditions.
a. Be separated from other parts of the building by fire resisting construction (minimum REI 30 in buildings with a top storey up to 5m above ground level; otherwise REI 60).
b. Not be situated within a protected stairway or protected lobby.
Access openings to refuse storage chambers should not be sited in the following areas.
a. Next to escape routes or final exits.
b. Near the windows of flats.
A building should provide access to more than one common stair if it does not meet the criteria for a single common stair (see paragraph 3.26 and 3.27).
Windows or external doors providing emergency escape should comply with all of the following.
a. Windows should have an unobstructed openable area that complies with all of the following.
i. A minimum area of 0.33m2.
ii. A minimum height of 450mm and a minimum width of 450mm (the route through the window may be at an angle rather than straight through).
iii. The bottom of the openable area is a maximum of 1100mm above the floor.
b. People escaping should be able to reach a place free from danger from fire.
c. Locks (with or without removable keys) and opening stays (with child-resistant release catches) may be fitted to escape windows.
d. Windows should be capable of remaining open without being held.
Every common stair should be a protected stairway. Where the protected stairway passes from one compartment to another, it should be within a protected shaft.
If a protected stairway projects beyond, is recessed from or is in an internal angle of the adjoining external wall of the building, then the minimum distance between an unprotected area of the building enclosure and an unprotected area of the stair enclosure should be 1800mm.
Any external escape stair should meet all of the following conditions (Diagram 3.11).
a. Doors to the stair should be fire resisting (minimum E 30) and be fitted with a self-closing device, except for a single exit door from the building to the top landing of a downward-leading external stair, provided it is the only door onto the landing.
b. Fire resisting construction (minimum RE 30) is required for the building envelope within the following zones, measured from the flights and landings of the external stair.
i. 1800mm above and horizontally.
ii. 9m vertically below.
iii. 1100mm above the top landing of the stair (except where the stair leads from basement to ground level).
c. Fire resisting construction (minimum RE 30) should be provided for any part of the building (including doors) within 1800mm of the escape route from the foot of the stair to a place of safety. This does not apply if there are alternative escape routes from the foot of the external escape stair.
d. Glazing in areas of fire resisting construction should be fixed shut and fire resisting (in terms of integrity but not insulation) (minimum E 30).
e. Stairs more than 6m in height above ground level (e.g. where they are provided above a podium) should be protected from adverse weather. Protection should prevent the build-up of snow or ice but does not require full enclosure.
See paras 3.27 and 3.36
NOTES:
1. The arrangements shown also apply to the top storey.
2. See Diagram 3.9 for small single stair buildings.
3. All doors shown are fire doorsets.
4. Where travel distance is measured to a stair lobby, the lobby must not provide direct access to any storage room, flat or other space containing a potential fire hazard.
5. For further guidance on the fire rating of the fire doorsets from the corridor to the flat and/or stairway refer to Appendix C ,Table C1.
F Flat
Shaded areas indicate zones where ventilation should be provided in accordance with paragraphs 3.50 to 3.53(An external wall vent or smoke shaft located anywhere in the shaded area)
See paras 3.27 and 3.36
NOTES:
1. The arrangements shown also apply to the top storey.
2. See Diagram 3.9 for small single stair buildings.
3. All doors shown are fire doorsets.
4. Where travel distance is measured to a stair lobby, the lobby must not provide direct access to any storage room, flat or other space containing a potential fire hazard.
5. For further guidance on the fire rating of the fire doorsets from the corridor to the flat and/or stairway refer to Appendix C ,Table C1.
F Flat
Shaded areas indicate zones where ventilation should be provided in accordance with paragraphs 3.50 to 3.53(An external wall vent or smoke shaft located anywhere in the shaded area)
The construction separating two adjacent protected stairways (or exit passageways leading to different final exits) should be imperforate.
If a building does not meet the criteria of paragraph 3.28, an escape stair forming part of the only escape route from an upper storey should not continue down to serve a basement storey. The basement storey should be served by a separate escape stair.
A protected stairway should not be used for anything else, except a lift well or electricity meters.
In single stair buildings, electricity meters should be in securely locked cupboards. Cupboards should be separated from the escape route by fire resisting construction.
Gas service and installation pipes and meters should not be within a protected stairway, unless installed in accordance with the Pipelines Safety Regulations 1996 and the Gas Safety (Installation and Use) Regulations 1998.
Every protected stairway should lead to a final exit, either directly or via a protected exit passageway. Any protected exit corridor or stair should have the same standard of fire resistance and lobby protection as the stair it serves.
Fixed ladders should not be provided as a means of escape for members of the public. They should only be provided where a conventional stair is impractical, such as for access to plant rooms which are not normally occupied.
The door of any doorway or exit should be hung to open in the direction of escape whenever reasonably practicable. It should always be hung to open in the direction of escape if more than 60 people might be expected to use it during a fire.
The surface linings of walls and ceilings should meet the classifications in Table 4.1.
Insulating core panels consist of an inner core of insulation sandwiched between, and bonded to, a membrane, such as galvanised steel or aluminium.
Where they are used internally they can present particular problems with regard to fire spread and should meet all of the following conditions.
a. Panels should be sealed to prevent exposure of the core to a fire. This includes at joints and where services penetrate the panel.
b. In high fire risk areas, such as kitchens, places of special fire hazard, or in proximity to where hot works occur, only class A1 cored panels should be used.
c. Fixing systems for all panels should be designed to take account of the potential for the panel to delaminate. For instance, where panels are used to form a suspended ceiling, the fixing should pass through the panel and support it from the lower face.
Materials within this zone – at plane of ceiling – should comply with Table 4.1
Rooflights
See Table 4.2
Rooflights should meet the following classifications, according to material. No guidance for European fire test performance is currently available, because there is no generally accepted test and classification procedure.
a. Non-plastic rooflights should meet the relevant classification in Table 4.1.
b. Plastic rooflights, if the limitations in Table 4.2 and Table 12.2 are observed, should be a minimum class D-s3, d2 rating. Otherwise they should meet the relevant classification in Table 4.1.
Any flexible membrane covering a structure, other than an air-supported structure, should comply with Appendix A of BS 7157.
Fire doors between the garage and dwellinghouse to have a minimum fire resistance of E30 Sa and be fitted with a self-closing device
Wall and any floor between the garage and dwellinghouse to have a minimum fire resistance of REI 30 from the garage side
The door opening threshold should be a minimum of 100mm above garage floor or
Floor to fall away from door to the outside
See paras 5.6 and 5.7
Elements of structure such as structural frames, beams, columns, loadbearing walls (internal and external), floor structures and gallery structures should have, as a minimum, the fire resistance given in Appendix B, Table B3.
A compartment wall should achieve both of the following.
a. Meet the underside of the roof covering or deck, with fire-stopping to maintain the continuity of fire resistance.
b. Be continued across any eaves.
Double-skinned insulated roof sheeting should incorporate a band of material rated class A2-s3, d2 or better, a minimum of 300mm in width, centred over the wall.
To reduce the potential for fire spread, cavity barriers should be provided for both of the following.
a. To divide cavities.
b. To close the edges of cavities.
Cavity barriers should not be confused with fire-stopping details (Section 9).
If one element of structure supports or stabilises another, as a minimum the supporting element should have the same fire resistance as the other element.
Cavity barriers should be tightly fitted to a rigid construction and mechanically fixed in position. If this is not possible (e.g. where a cavity barrier joins to slates, tiles, corrugated sheeting or similar materials) the junction should be fire-stopped.
Dwellinghouses that are semi-detached or in terraces should be considered as separate buildings. Every wall separating the dwellinghouses should be constructed as a compartment wall (see paragraphs 5.8 to 5.12).
If a garage is attached to or forms an integral part of a dwellinghouse, the garage should be separated from the rest of the dwellinghouse by fire resisting construction (minimum REI 30) (Diagram 5.1).
Where a door is provided between a dwellinghouse and the garage (see Diagram 5.1), it should meet one of the following conditions.
a. The garage floor should be laid such that it falls away from the door to the outside, to allow fuel spills to flow away.
b. The door opening should be a minimum of 100mm above the level of the garage floor.
Timber beams, joists, purlins and rafters may be built into or carried through a masonry or concrete compartment wall if the openings for them are both of the following.
a. As small as practicable.
b. Fire-stopped.
If trussed rafters bridge the wall, failure of the truss due to a fire in one compartment should not cause failure of the truss in another compartment.
Elements of structure such as structural frames, beams, columns, loadbearing walls (internal and external), floor structures and gallery structures should have, as a minimum, the fire resistance given in Appendix B, Table B3.
NOTE: If one element of structure supports or stabilises another, as a minimum the supporting element should have the same fire resistance as the other element.
All of the following should be provided as compartment walls and compartment floors and should have, as a minimum, the fire resistance given in Appendix B, Table B3.
a. Any floor (unless it is within a flat, i.e. between one storey and another within one individual dwelling).
b. Any wall separating a flat from another part of the building.
c. Any wall enclosing a refuse storage chamber.
d. Any wall common to two or more buildings.
Compartment walls not described in paragraphs 7.8 and 7.9 should run the full height of the storey in which they are situated.
Compartment walls in a top storey beneath a roof should be continued through the roof space.
At the junction with another compartment wall or an external wall, the fire resistance of the compartmentation should be maintained. Fire-stopping that meets the provisions in paragraphs 9.24 to 9.29 should be provided.
At the junction of a compartment floor and an external wall with no fire resistance, the external wall should be restrained at floor level. The restraint should reduce movement of the wall away from the floor if exposed to fire.
Compartment walls should be able to accommodate deflection of the floor, when exposed to fire, by either of the following means.
a. Between the wall and floor, provide a head detail that is capable of maintaining its integrity while deforming.
b. Design the wall so it maintains its integrity by resisting the additional vertical load from the floor above.
Where compartment walls are located within the middle half of a floor between vertical supports, the deflection may be assumed to be 40mm unless a smaller value can be justified by assessment. Outside this area, the limit can be reduced linearly to zero at the supports.
For steel beams that do not have the required fire resistance, reference should be made to SCI Publication P288.
Double-skinned insulated roof sheeting with a thermoplastic core should incorporate a band of material rated class A2-s3, d2 or better, a minimum of 300mm in width, centred over the wall.
Where the measures in Diagram 7.2 are not provided, then both of the following apply.
a. The enclosing walls should comply with Appendix B, Table B3.
b. The doors should comply with Appendix B, Table B5.
A protected shaft conveying piped flammable gas should be ventilated direct to the outside air, by ventilation openings at high and low level in the shaft.
Any extension of the storey floor into the protected shaft should not compromise the free movement of air throughout the entire length of the shaft.
Guidance on shafts conveying piped flammable gas, including the size of ventilation openings, is given in BS 8313.
Blocks of flats with a top storey more than 11m above ground level (see Diagram D6) should be fitted with a sprinkler system throughout the building in accordance with Appendix E.
NOTE: Sprinklers should be provided within the individual flats, they do not need to be provided in the common areas such as stairs, corridors or landings when these areas are fire sterile.
Timber beams, joists, purlins and rafters may be built into or carried through a masonry or concrete compartment wall if the openings for them are both of the following.
a. As small as practicable.
b. Fire-stopped.
If trussed rafters bridge the wall, failure of the truss due to a fire in one compartment should not cause failure of the truss in another compartment.
Where services could provide a source of ignition, the risk of fire developing and spreading into adjacent compartments should be controlled.
Compartment walls forming a separated part of a building should run the full height of the building in a continuous vertical plane.
Separated parts can be assessed independently to determine the appropriate standard of fire resistance in each. The two separated parts can have different standards of fire resistance.
To reduce the potential for fire spread, cavity barriers should be provided for both of the following.
a. To divide cavities.
b. To close the edges of cavities.
See Diagram 8.1. Cavity barriers should not be confused with fire-stopping details (Section 9).
NOTE:
The ceiling should meet the following conditions.
a. Provide a minimum fire resistance of EI 30.
b. Be imperforate, except for an opening described in paragraph 5.24.
c. Extend through out the building or compartment.
d. Not be easily demountable.
See para 8.5
The insulation should make contact with both skins of sheeting. See also Diagram 5.2a regarding the need for fire-stopping where such roofs pass over the top of a compartment wall.
See para 8.7
In divided corridors (paragraph 3.25 and following) with cavities, fire-stopping should be provided to prevent alternative escape routes being affected by fire and/or smoke.
Cavity barriers should meet the requirements set out in paragraphs 5.21 to 5.24.
NOTES:
1. The enclosure should meet all of the following conditions.
a. Be bounded by a compartment wall or floor, an outside wall, an intermediate floor or a casing(see specification at 2 below).
b. Have internal surfaces (except framing members)of class B-s3, d2 or better.
Note: when a classification includes ‘s3, d2’, this means that there is no limit set for smoke production and/or flaming droplets/particles).
c. Not have an access panel which opens into a circulation space or bed room.
d. Be used only for drainage or water supply or vent pipes for a drainage system.
2.The casing should meet all the following conditions.
a. Be imperforate except for an opening for a pipe
or an access panel.
b. Not be of sheet metal.
c. Not have fire resistance less than E 30 (including any access panel).
3.The opening for a pipe, in either the element of structure or the casing, should be as small as possible and fire-stopped around the pipe.
See para 9.4 and Table 9.1
In mixed use buildings, non-domestic kitchens, car parks and plant rooms should have separate and independent extraction systems. Extracted air should not be recirculated.
Under fire conditions, ventilation and air-conditioning systems should be compatible with smoke control systems and need to be considered in their respective design.
Where ducts pass between fire-separating elements to serve multiple flats or dwellings, fire dampers or fire and smoke dampers should be actuated by both of the following.
a. Smoke detector-controlled automatic release mechanisms.
b. Thermally actuated devices.
Method 1 should not be used for extract ductwork passing through the enclosures of protected escape routes (Diagrams 9.3 and 9.4), as large volumes of smoke can pass thermal devices without triggering them.
Access to the fire damper and its actuating mechanism should be provided for inspection, testing and maintenance.
Pipes passing through a fire-separating element, unless in a protected shaft, should meet one of the alternatives A, B or C below.
Fire dampers should meet both of the following conditions.
a. Conform to BS EN 15650.
b. Have a minimum E classification of 60 minutes or to match the integrity rating of the fire resisting elements, whichever is higher.
Fire and smoke dampers should meet both of the following conditions.
a. Conform to BS EN 15650.
b. Have a minimum ES classification of 60 minutes or to match the integrity rating of the fire resisting elements, whichever is higher.
Smoke detectors should be sited so as to prevent the spread of smoke as early as practicable by activating the fire and smoke dampers. Smoke detectors and automatic release mechanisms used to activate fire dampers and/or fire and smoke dampers should conform to BS EN 54-7 and BS 5839-3 respectively.
Further information on fire dampers and/or fire and smoke dampers is given in the ASFP Grey Book.
The wall of a flue, duct containing flues or appliance ventilation duct(s) should have a fire resistance (REI) that is at least half of any compartment wall or compartment floor it passes through or is built into (Diagram 9.5).
In addition to any other provisions in this section, both of the following conditions should be met.
a. Joints between fire-separating elements should be fire-stopped.
b. Openings through a fire resisting element for pipes, ducts, conduits or cable should be all of the following.
i. As few as possible.
ii. As small as practicable.
iii. Fire-stopped (allowing thermal movement in the case of a pipe or duct).
NOTE: The fire-stopping around fire dampers, fire resisting ducts, fire and smoke dampers and smoke control ducts should be in accordance with the manufacturer or supplier’s installation instructions.
Where a proprietary sealing system is not used, fire-stop around the pipe, keeping the opening for the pipe as small as possible. The nominal internal diameter of the pipe should not exceed the relevant dimension given in Table 9.1. The diameter given in Table 9.1 for pipes of specification (b) used in situation 2 or 3 assumes that the pipes are part of an above-ground drainage system and are enclosed as shown in Diagram 9.1. If they are not, the smaller diameter given for situation 5 should be used.
a. Flue passing through compartment wall or floor
b. Flue built into compartment wall
Flue walls should have a fire resistance of at least one half of that required for the compartment wall or floor and be of class A1construction.
In each case flue walls should have a fire resistance of at least one half of that required for the compartment wall and be of class A1 construction.
See para 9.23
Ductwork should not help to transfer fire and smoke through the building. Terminals of exhaust points should be sited away from final exits, cladding or roofing materials achieving class B-s3, d2 or worse and openings into the building.
Ventilation ducts supplying or extracting air directly to or from a protected stairway should not also serve other areas. A separate ventilation system should be provided for each protected stairway.
A fire and smoke damper should be provided where ductwork enters or leaves each section of the protected escape route it serves. It should be operated by a smoke detector or suitable fire detection system. Fire and smoke dampers should close when smoke is detected. Alternatively, the methods set out in paragraphs 9.16 and 9.17 and Diagrams 9.3 and 9.4 may be followed.
In a system that recirculates air, smoke detectors should be fitted in the extract ductwork before both of the following.
a. The point where recirculated air is separated from air to be discharged to the outside.
b. Any filters or other air cleaning equipment.
When smoke is detected, detectors should do one of the following.
i. Cause the system to immediately shut down.
ii. Switch the ventilation system from recirculating mode to extraction to divert smoke to outside the building.
The following guidance should be used when applying the fire resistance standards in Table B4.
a. If one element of structure supports or carries or gives stability to another, the fire resistance
of the supporting element should be no less than the minimum period of fire resistance for the
other element (whether that other element is loadbearing or not). In some circumstances, it
may be reasonable to vary this principle, for example:
i. if the supporting structure is in the open air and is not likely to be affected by the fire in
the building
ii. if the supporting structure is in a different compartment, with a fire-separating element
(that has the higher standard of fire resistance) between the supporting and the separated
structure
iii. if a plant room on the roof needs greater fire resistance than the elements of structure
that support it.
b. If an element of structure forms part of more than one building or compartment, that element
should be constructed to the standard of the higher of the relevant provisions.
c. If, due to the slope of the ground, one side of a basement is open at ground level (allowing
smoke to vent and providing access for firefighting) for elements of structure in that storey
it may be appropriate to adopt the standard of fire resistance that applies to above-ground
structures.
d. Although most elements of structure in a single storey building may not need fire resistance,
fire resistance is needed if one of the following applies to the element.
i. It is part of, or supports, an external wall, and there is provision in the guidance on
requirement B4 to limit the extent of openings and other unprotected areas in the wall.
ii. It is part of, or supports, a compartment wall, including a wall that is common to two or
more buildings.
iii. It supports a gallery.
Assessments should not be regarded as a way to avoid a test where one is necessary. Assessments should only be carried out where sufficient relevant test evidence is available. Relevant test evidence is unlikely to be provided by test standards which have different classification criteria.
Tests and assessments should be carried out by organisations with the necessary expertise. For NOTE: Standard fire tests do not directly measure fire hazard. They measure or assess the response
example, organisations listed as ‘notified bodies’ in accordance with the European Construction Products Regulation or laboratories accredited by the United Kingdom Accreditation Service (UKAS)
for the relevant test standard can be assumed to have the necessary expertise.
of a material or system to exposure to one or more aspects of fire conditions. Performance in fire
tests is only one of a number of factors that should be taken into account.
All fire doorsets should have the performance shown in Table C1, based on one of the following.
a. Fire resistance in terms of integrity, for a period of minutes, when tested to BS 476-22, e.g. FD 30.
A suffix (S) is added for doorsets where restricted smoke leakage at ambient temperatures is
needed.
b. As determined with reference to Commission Decision 2000/367/EC regarding the
classification of the resistance to fire performance of construction products, construction
works and parts thereof. All fire doorsets should be classified in accordance with BS EN 13501-2,
tested to the relevant European method from the following.
i. BS EN 1634-1.
ii. BS EN 1634-2.
iii. BS EN 1634-3.
c. As determined with reference to European Parliament and Council Directive 95/16/EC (which
applies to lifts that permanently serve buildings and constructions and specified safety
components) on the approximation of laws of Member States relating to lifts (‘Lifts Directive’)
implementing the
Unless shown to be satisfactory when tested as part of a fire doorset assembly, the essential components of any hinge on which a fire door is hung should be made entirely from materials that have a minimum melting point of 800°C.
Except for doorsets listed in paragraph C12, all fire doorsets should be marked with one of the
following fire safety signs, complying with BS 5499-5, as appropriate.
a. To be kept closed when not in use – mark ‘Fire door keep shut’.
b. To be kept locked when not in use – mark ‘Fire door keep locked shut’.
c. Held open by an automatic release mechanism or free swing device – mark ‘Automatic fire door
keep clear’.
All fire doorsets should be marked on both sides, except fire doorsets to cupboards and service
ducts, which should be marked on the outside.
All fire doorsets, including to flat entrances and between a dwellinghouse and an integral garage,
should be fitted with a self-closing device, except for all of the following.
a. Fire doorsets to cupboards.
b. Fire doorsets to service ducts normally locked shut.
c. Fire doorsets within flats and dwellinghouses.
Fire doorsets often do not provide any significant insulation. Unless providing both integrity
and insulation in accordance with Appendix B, Table B3, a maximum of 25% of the length of a
compartment wall should consist of door openings.
Where it is practicable to maintain a clear space on both sides of the doorway, the above
percentage may be greater.
Rolling shutters should be capable of manual opening and closing for firefighting purposes (see Section 15). Rolling shutters across a means of escape should only be released by a heat sensor, such as a fusible link or electric heat detector, in the immediate vicinity of the door. Unless a shutter is also intended to partially descend as part of a boundary to a smoke reservoir, shutters across a means of escape should not be closed by smoke detectors or a fire alarm system.
Counters and display units should be included when measuring area. All of the following should
be excluded.
a. Stair enclosures.
b. Lifts.
c. Sanitary accommodation.
d. Any other fixed part of the building structure.
Travel distance is measured as the shortest route. Both of the following should be observed.
a. If there is fixed seating or other fixed obstructions, the shortest route is along the centre line of
the seatways and gangways.
b. If the route includes a stair, the shortest route is along the pitch line on the centre line of travel.
Where required, sprinkler systems should be provided throughout the building or separated part,
unless acting as a compensatory feature to address a specific risk. They should be designed and
installed in accordance with the following.
a. For residential buildings, the requirements of BS 9251.
b. For non-residential buildings, or residential buildings outside the scope of BS 9251, the
requirements of BS EN 12845, including the relevant hazard classification together with
additional measures to improve system reliability and availability as described in Annex F of the
standard.
NOTE: Any sprinkler system installed to satisfy the requirements of Part B of the Building
Regulations should be provided with additional measures to improve system reliability and
availability and is therefore to be regarded as a life safety system. However, there may be some
circumstances in which additional measures to improve system reliability and availability specified
in Annex F of BS EN 12845 are inappropriate or unnecessary.
For non-residential sprinkler systems designed and installed to BS EN 12845, water supplies should
consist of either of the following.
a. Two single water supplies complying with clause 9.6.1, independent of each other.
b. Two stored water supplies meeting all of the following conditions.
i. Gravity or suction tanks should satisfy all the requirements of clause 9.6.2(b), other than
capacity.
ii. Any pump arrangements should comply with clause 10.2.
iii. In addition to meeting the requirements for inflow, either of the following should apply.
• The capacity of each tank should be at least half the specified minimum water volume
of a single full capacity tank, appropriate to the hazard.
• One tank should be at least equivalent to half the specified water volume of a single
full capacity tank, and the other shall not be less than the minimum volume of a
reduced capacity tank (see clause 9.3.4) appropriate to the hazard.
The total capacity of the water supply in (iii), including any inflow for a reduced capacity
tank, should be at least that of a single full holding capacity tank that complies with
For the systems described in paragraph E5, both of the following apply if pumps are used to draw
water from two tanks.
a. Each pump should be able to draw water from either tank.
b. Any one pump, or either tank, should be able to be isolated.
The sprinkler water supplies should not be used as connections for other services or other fixed
firefighting systems.
significant risks
Sprinkler systems installed in buildings can reduce the risk to life and significantly reduce the
degree of damage caused by fire within a building.
single storey
NOTES:
For single storey buildings, the periods under the heading ‘Up to 5’ apply. If single storey buildings have basements, for the basement storeys the period appropriate to their depth applies.
* For the floor over a basement or, if there is more than one basement, the floor over the topmost basement, the higher of the period for the basement storey and the period for the ground or upper storey applies.
† For compartment walls that separate buildings, the period is increased to a minimum of 60 minutes.
+ For any floor that does not contribute to the support of the building within a flat of more than one storey, the period is reduced to 30 minutes.
§ For flat conversions, refer to paragraphs 6.5 to 6.7 regarding the acceptability of 30 minutes.
‡ For elements that do not form part of the structural frame, the period is reduced to 90 minutes.
# For elements that protect the means of escape, the period is increased to 30 minutes.
1. Refer to note 1, Table B3 for the specific provisions of test.
2. Blocks of flats with a floor more than 30m above ground level should be fitted with a sprinkler system in accordance with Appendix E.
NOTE:
Sprinklers only need to be provided within the individual flats, they are not required in the common areas such as stairs, corridors or landings when these areas are fire sterile.
3.‘With sprinkler system’ means that the building is fitted throughout with an automatic sprinkler system in accordance with Appendix E.
4. Very large (over 18m in height or with a 10m deep basement) or unusual dwellinghouses are outside the scope of the guidance provided with regard to dwellinghouses.
5. A minimum of 30 minutes in the case of three storey dwellinghouses, increased to 60 minutes minimum for compartment walls separating buildings.
6. Buildings within the ‘office’, ‘shop and commercial’, ‘assembly and recreation’, ‘industrial’ and ‘storage and other non-residential’ (except car parks for light vehicles) purpose groups (purpose groups 3 to 7(a)) require sprinklers where there is a top storey above 30m.
The sprinkler system should be provided in accordance with Appendix E.
7. The car park should comply with the relevant provisions in the guidance on requirement B3, Section 11 of
Approved Document B Volume 2.
8. For the purposes of meeting the Building Regulations, the following types of steel elements are deemed to have satisfied the minimum period of fire resistance of 15 minutes when tested to the European test method.
i. Beams supporting concrete floors, maximum Hp/A=230m-1 operating under full design load.
ii. Free-standing columns, maximum Hp/A=180m-1 operating under full design load.
iii. Wind bracing and struts, maximum Hp/A=210m-1 operating under full design load.
Guidance is also available in BS EN 1993-1-2.
Flats
1. Within the enclosures of a protected entrance hall or protected landing, or within fire resisting separation shown in Section 3, Diagram 3.4.
2. Within either:
a. the enclosures of a protected stairway
b. fire resisting separation shown in Diagram 2.2.
3. Within fire resisting separation either:
a. shown in Diagram 2.4
b. described in paragraph 2.16b.
4. Existing window between an attached/integral garage and the dwellinghouse.
5. Adjacent to an external escape stair (see paragraph 2.17 and Diagram 2.7) or roof escape route (see paragraph 2.13).
6. Between residential/sleeping accommodation and a common escape route (corridor, lobby or stair).
7. Between a protected stairway(1)and either:
a. the accommodation
b. a corridor that is not a protected corridor other than in item 6 above.
8. Between either:
a. a protected stairway(1)and a protected lobby or protected corridor
b. accommodation and a protected lobby other than in item 6 above.
9. Between the accommodation and a protected corridor that forms a dead end,other than in item 6 above.
10.Between accommodation and any other corridor, or sub-dividing corridors,other than in item 6 above.
11. Beside an external escape route.
Table B5
see Table B3
Table B5
12. Beside an external escape stair (see paragraph 3.68 and Diagram 3.11) or roof escape route (see paragraph 3.30).
NOTES:
Items 1 and 8 apply also to single storey buildings.
Fire resisting glass should be marked with the name of the manufacturer and the name of the product.
Further guidance can be found in A Guide to Best Practice in the Specification and Use of Fire-resistant Glazed Systems published by the Glass and Glazing Federation.
1. If the protected stairway is also a protected shaft or a firefighting stair (see Section 15), there may be further
restrictions on the use of glazed elements.
2. Measured vertically from the landing floor level or the stair pitch line.
3. The 100mm limit is intended to reduce the risk of fire spreading from a floor covering.
While many of the provisions in this approved document for means of escape from flats are applicable to sheltered housing, the nature of the occupancy may necessitate some additional fire protection measures. The extent of such measures will depend on the form of the development. For example, a group of specially adapted bungalows or two storey flats, with few communal facilities, will not need to be treated differently from other single storey or two storey dwellinghouses or flats.
See paras 2.1 to 2.6
Single storey dwellinghouse(see paragraph 2.1)
Dwellinghouse with one storey more than 4.5m above ground level(see paragraph 2.5)
Dwellinghouse with two or more storeys more than 4.5m above ground level(see paragraph 2.6)
A lift shaft serving storeys above ground level should not serve any basement, if either of the following applies.
a. There is only one escape stair serving storeys above ground level and smoke from a basement fire would adversely affect escape routes in the upper storeys.
b. The lift shaft is within the enclosure to an escape stair that terminates at ground level.
The internal arrangement of single storey or multi-storey flats should comply with paragraphs 3.15 to 3.17. Alternatively, the guidance in paragraphs 3.18 to 3.22 may be followed.
Where a flat is accessed via the common parts of a block of flats it may be necessary to provide a protected entrance hall to meet the provisions of paragraph 3.28 and Diagram 3.9.
From the flat entrance door, a single escape route is acceptable in either of the following cases.
a. The flat is on a storey served by a single common stair and both of the following apply.
i. Every flat is separated from the common stair by a protected lobby or common protected corridor (see Diagram 3.7).
ii. The maximum travel distance in Table 3.1, for escape in one direction only, is not exceeded.
b. The flat is in a dead end of a common corridor served by two (or more) common stairs and the maximum travel distance given in Table 3.1, for escape in one direction only, is not exceeded (Diagram 3.8).
In single stair buildings, smoke vents on the storey where the fire is initiated, and the vent at the head of the stair, should be activated by smoke detectors in the common parts.
In buildings with more than one stair, smoke vents may be activated manually. The control system should open the vent at the head of the stair before, or at the same time as, the vent on the storey where the fire is located. Smoke detection is not required for ventilation purposes in this instance.
Where a storey (or part of a building) is served by a single access stair, that stair may be external provided both of the following conditions are met.
a. The stair serves a floor not more than 6m above the ground level.
b. The stair meets the provisions in paragraph 3.68.
a. SMALL SINGLE STAIR BUILDING
*If smoke control is provided in the lobby, the travel distance can be increased to 7.5m maximum(see Diagram 3.7, example b).
b. SMALL SINGLE STAIR BUILDING WITH NO MORE THAN TWO FLATS PER STOREY
The door between stair and lobby should be free from security fastenings.
If the flats have protected entrance halls, the lobby between the common stair and flat entrance is not essential.
NOTES:
1. The arrangements shown also apply to the top storey.
2. If the travel distance across the lobby in diagram (a) exceeds 4.5m, Diagram 3.7 applies.
3. Where,in Diagram (b), the lobby between the common stair and the dwelling is omitted in smal lsingle stair buildings, an automatic opening vent with a free area of at least 1m2 is required at the top of the stair,which is operated automatically on detection of smoke at any storey in the stair.
4. For further guidance on the fire rating of the fire doorsets from the corridor to the flat and/or stairway refer to Appendix C, Table C1.
Fire resisting construction
Openable vent at high level for fire service use (1.0m2 minimum free area); see paragraph 3.28eSee para 3.28
Diagram 3.9
Where adding an additional storey to a two storey single family dwellinghouse, new floors should have a minimum REI 30 fire resistance. Any floor forming part of the enclosure to the circulation space between the loft conversion and the final exit should achieve a minimum rating of REI 30.
The existing first-storey construction should have a minimum rating of R 30. The fire performance may be reduced for integrity and insulation, when both of the following conditions are met.
a. Only one storey is added, containing a maximum of two habitable rooms.
b. The new storey has a maximum total area of 50m2.
The following guidance should be used when applying the fire resistance standards in Table B4.
a. If one element of structure supports or carries or gives stability to another, the fire resistance
of the supporting element should be no less than the minimum period of fire resistance for the
other element (whether that other element is loadbearing or not). In some circumstances, it
may be reasonable to vary this principle, for example:
i. if the supporting structure is in the open air and is not likely to be affected by the fire in
the building
ii. if the supporting structure is in a different compartment, with a fire-separating element
(that has the higher standard of fire resistance) between the supporting and the separated
structure
iii. if a plant room on the roof needs greater fire resistance than the elements of structure
that support it.
b. If an element of structure forms part of more than one building or compartment, that element
should be constructed to the standard of the higher of the relevant provisions.
c. If, due to the slope of the ground, one side of a basement is open at ground level (allowing
smoke to vent and providing access for firefighting) for elements of structure in that storey
it may be appropriate to adopt the standard of fire resistance that applies to above-ground
structures.
d. Although most elements of structure in a single storey building may not need fire resistance,
fire resistance is needed if one of the following applies to the element.
i. It is part of, or supports, an external wall, and there is provision in the guidance on
requirement B4 to limit the extent of openings and other unprotected areas in the wall.
ii. It is part of, or supports, a compartment wall, including a wall that is common to two or
more buildings.
iii. It supports a gallery.
For the purposes of this paragraph, the ground storey of a building that has one or more basement storeys and no upper storeys may be considered as a single storey building. The fire resistance of the basement storeys should be that specified for basements.
site
Guidance on aspects of the provision and siting of private fire hydrants is given in BS 9990.
Refuse storage chambers, refuse chutes and refuse hoppers should be sited and constructed in accordance with BS 5906.
solid biofuel
Thermoplastic material is any synthetic polymeric material that has a softening point below 200°C if tested to BS EN ISO 306 Method A120. Products formed from these materials cannot always be classified in the normal way. In those circumstances the following approach can be followed.
For the purposes of requirements B2 and B4, thermoplastic materials should be classified as TP(a)
rigid, TP(a) flexible or TP(b), as follows:
a. TP(a) rigid
i. rigid solid uPVC sheet
ii. solid (as distinct from double- or multi-skinned) polycarbonate sheet a minimum of 3mm
thick
iii. multi-skinned rigid sheet made from uPVC or polycarbonate that has a class 1 rating when
tested to BS 476-7
iv. any other rigid thermoplastic product, a specimen of which (at the thickness of the
product as put on the market), when tested to BS 2782-0 Method 508A, performs so that
both:
• the test flame extinguishes before the first mark
• the duration of flaming or afterglow does not exceed 5 seconds following removal of
the burner.
b. TP(a) flexible
Flexible products a maximum of 1mm thick that comply with the Type C requirements
of BS 5867-2 when tested to BS 5438 Test 2 with the flame applied to the surface of the
specimens for 5, 15, 20 and 30 seconds respectively, but excluding the cleansing procedure; and
c. TP(b)
i. rigid solid polycarbonate sheet products a maximum of 3mm thick, or multi-skinned
polycarbonate sheet products that do not qualify as TP(a) by test
ii. other products which, when a specimen of the material between 1.5 and 3mm thick is
tested in accordance with BS 2782-0 Method 508A, have a maximum rate of burning of
50mm/minute.
NOTE: If it is not possible to cut or machine a 3mm thick specimen from the product, then a 3mm
spacing
Smoke alarms should be provided in the circulation spaces of the dwelling in accordance with paragraphs 1.1 to 1.4.
See para 2.5
Alternative cavity barrier arrangements in roof space over protected stairway in a house with a storey more than 4.5m above ground level
Compartment walls in a top storey beneath a roof should be continued through the roof space.
span
Particular attention is drawn to the following points.
a. Membranes used as part of the external wall construction above ground level should achieve a minimum of class B-s3, d0. Roofing membranes do not need to achieve a minimum of class A2-s1, d0 when used as part of a roof connecting to an external wall.
b. Internal linings should comply with the guidance provided in Section 4.
c. Any part of a roof should achieve the minimum performance as detailed in Section 12.
d. As per regulation 7(3), window frames and glass (including laminated glass) are exempted
from regulation 7(2). Window spandrel panels and infill panels must comply with regulation 7(2).
e. Thermal breaks are small elements used as part of the external wall construction to restrict
thermal bridging. There is no minimum performance for these materials. However, they
should not span two compartments and should be limited in size to the minimum required
to restrict the thermal bridging (the principal insulation layer is not to be regarded as a
thermal break).
f. Regulation 7(2) only applies to specified attachments. Shop front signs and similar attachments are
not covered by the requirements of regulation 7(2), although attention is drawn to paragraph 10.21g.
g. While regulation 7(2) applies to materials which become part of an external wall or specified
attachment, consideration should be given to other attachments to the wall which could
impact on the risk of fire spread over the wall.
h. Any material achieving class A1fl or A2fl-s1 in accordance with BS EN 13501-1 is exempted when it
meets both of the following conditions.
i. It forms the top horizontal floor layer of a balcony.
ii. It is provided with an imperforate substrate under it which extends to the full size of the
class A1fl or A2fl-s1 material.
Materials used for fire-stopping should be reinforced with (or supported by) materials rated class A2-s3, d2 or better to prevent displacement in both of the following cases.
a. Where the unsupported span is greater than 100mm.
b. Where non-rigid materials are used (unless subjected to appropriate fire resistance testing to show their suitability).
specialist designer
Guidance on the design, installation and maintenance of measures to contain fires or slow their spread is given in Ensuring Best Practice for Passive Fire Protection in Buildings produced by the Association for Specialist Fire Protection (ASFP).
specified attachment
External fire spread
B4.(1)The external walls of the building shall adequately resist the spread of fire over the walls and from one building to another, having regard to the height, use and position of the building.
(2)The roof of the building shall adequately resist the spread of fire over the roof and from one building to another, having regard to the use and position of the building.
Regulation 7 – Materials and workmanship
(1)Building work shall be carried out—
(a)with adequate and proper materials which—
(i)are appropriate for the circumstances in which they are used,
(ii)are adequately mixed or prepared, and
(iii)are applied, used or fixed so as adequately to perform the functions for which they are designed; and
(b)in a workmanlike manner.
(2)Subject to paragraph (3), building work shall be carried out so that materials which become part of an external wall, or specified attachment, of a relevant building are of European Classification A2-s1, d0 or A1, classified in accordance with BS EN 13501-1:2007+A1:2009 entitled “Fire classification of construction products and building elements. Classification using test data from reaction to fire tests” (ISBN 978 0 580 59861 6) published by the British Standards Institution on 30th March 2007 and amended in November 2009.
(3)Paragraph (2) does not apply to—
(a)cavity trays when used between two leaves of masonry;
(b)any part of a roof (other than any part of a roof which falls within paragraph (iv) of regulation 2(6))if that part is connected to an external wall;
(c)door frames and doors;
(d)electrical installations;
(e)insulation and water proofing materials used below ground level;
(f)intumescent and fire stopping materials where the inclusion of the materials is necessary to meet the requirements of Part B of Schedule 1;
(g)membranes;
(h)seals, gaskets, fixings, sealants and backer rods;
(i)thermal break materials where the inclusion of the materials is necessary to meet the thermal bridging requirements of Part L of Schedule 1; or
(j)window frames and glass.
(4)In this regulation—
(a)a “relevant building” means a building with a storey (not including roof-top plant areas or any storey consisting exclusively of plant rooms) at least 18 metres above ground level and which—
(i)contains one or more dwellings;
(ii)contains an institution; or
(iii)contains a room for residential purposes(excluding any room in a hostel, hotel or boarding house); and
(b)“above ground level” in relation to a storey means above ground level when measured from the lowest ground level adjoining the outside of a building to the top of the floor surface of the storey.
Table 10.1 Reaction to fire performance of external surface of walls
‘Relevant buildings’ as defined in regulation 7(4) (see paragraph 10.10)
NOTES:
In addition to the requirements within this table, buildings with a top occupied storey above 18m should also meet the provisions of paragraph 10.6.
In all cases, the advice in paragraph 10.4 should be followed.
1. The restrictions for these buildings apply to all the materials used in the external wall and specified attachments (see paragraphs 10.9 to 10.12 for further guidance).
2. Profiled or flat steel sheet at least 0.5 mm thick with an organic coating of no more than 0.2mm thickness is also acceptable.
3. Timber cladding at least 9mm thick is also acceptable.
4. 10m is measured from the top surface of the roof.
Regulation 7(1)(a) requires that materials used in building work are appropriate for the circumstances in which they are used. Regulation 7(2) sets requirements in respect of external walls and specified attachments in relevant buildings.
NOTE: Further guidance on regulation 7(1) can be found in HM Government’s Manual to the Building Regulations.
Regulation 7(2) applies to any building with a storey at least 18m above ground level (as
measured in accordance with Diagram D6 in Appendix D) and which contains one or more
dwellings; an institution; or a room for residential purposes. It requires that all materials which become part of an external wall or specified attachment achieve class A2-s1, d0 or class A1 in accordance with BS EN 13501-1, other than those exempted by regulation 7(3).
NOTE: The above includes student accommodation, care homes, sheltered housing, hospitals, dormitories in boarding schools, hotels, hostels and boarding houses. See regulation 7(4) for the definition of relevant buildings.
NOTE: Transposition to national class (Table B1) does not apply to the classification in this paragraph.
External walls and specified attachments are defined in regulation 2(6) and these definitions
include any parts of the external wall as well as balconies, solar panels and solar shading.
Regulation 7(3) provides an exemption for certain components found in external walls and specified attachments.
Regulations 5(k) and 6(3) provide that, where the use of a building is changed such that the building becomes a building described in regulation 7(4), the construction of the external walls, and specified attachments, must be investigated and, where necessary, work must be carried out to ensure they only contain materials achieving class A2-s1, d0 or class A1, other than those exempted by regulation 7(3).
The provisions of regulation 7 apply in addition to requirement B4. Therefore, for buildings described in regulation 7(4), the potential impact of any products incorporated into or onto the external walls and specified attachments should be carefully considered with regard to their number, size, orientation and position.
Particular attention is drawn to the following points.
a. Membranes used as part of the external wall construction above ground level should achieve a minimum of class B-s3, d0. Roofing membranes do not need to achieve a minimum of class A2-s1, d0 when used as part of a roof connecting to an external wall.
b. Internal linings should comply with the guidance provided in Section 4.
c. Any part of a roof should achieve the minimum performance as detailed in Section 12.
d. As per regulation 7(3), window frames and glass (including laminated glass) are exempted
from regulation 7(2). Window spandrel panels and infill panels must comply with regulation 7(2).
e. Thermal breaks are small elements used as part of the external wall construction to restrict
thermal bridging. There is no minimum performance for these materials. However, they
should not span two compartments and should be limited in size to the minimum required
to restrict the thermal bridging (the principal insulation layer is not to be regarded as a
thermal break).
f. Regulation 7(2) only applies to specified attachments. Shop front signs and similar attachments are
not covered by the requirements of regulation 7(2), although attention is drawn to paragraph 10.21g.
g. While regulation 7(2) applies to materials which become part of an external wall or specified
attachment, consideration should be given to other attachments to the wall which could
impact on the risk of fire spread over the wall.
h. Any material achieving class A1fl or A2fl-s1 in accordance with BS EN 13501-1 is exempted when it
meets both of the following conditions.
i. It forms the top horizontal floor layer of a balcony.
ii. It is provided with an imperforate substrate under it which extends to the full size of the
class A1fl or A2fl-s1 material.
spiral stair
The flights and landings of escape stairs should be constructed of materials achieving class A2-s3, d2 or better in all of the following situations.
a. If the escape stair is the only stair in a building with more than three storeys.
b. If the escape stair is within a basement storey.
c. If the escape stair serves any storey that has a floor level more than 18m above ground or access level.
d. If the escape stair is an external escape stair, except where the stair connects the ground storey or ground level with a floor or flat roof a maximum of 6m above or below ground level.
e. If the escape stair is a firefighting stair.
Materials achieving class B-s3, d2 or worse may be added to the top horizontal surface, except on firefighting stairs.
Further guidance on the construction of firefighting stairs is given in Section 15 (see also paragraph 3.60). Dimensional constraints on the design of stairs are given in Approved Document K.
Helical stairs and spiral stairs may form part of an escape route provided they are designed in accordance with BS 5395-2. If they are intended to serve members of the public, stairs should be type E (public) stairs.
stair width
A stair of acceptable width for everyday use will be sufficient for escape purposes. If it is also a firefighting stair, it should be at least 1100mm wide. The width is the clear width between the walls or balustrades. Any handrails and strings intruding into that width by a maximum of 100mm on each side may be ignored.
All doors on escape routes should be hung to meet both of the following conditions.
a. Open by a minimum of 90 degrees.
b. Open with a swing that complies with both of the following.
i. Is clear of any change of floor level, other than a threshold or single step on the line of the doorway.
ii. Does not reduce the effective width of any escape route across a landing.
Any door opening towards a corridor or a stair should be recessed to prevent its swing encroaching on the effective width.
Width is measured according to the following.
a. For a door (or doorway), the clear width when the door is open (Diagram D1).
b. For an escape route, either of the following.
i. When the route is defined by walls: the width at 1500mm above finished floor level.
ii. Elsewhere: the minimum width of passage available between any fixed obstructions.
c. For a stair, the clear width between the walls or balustrades. On escape routes and stairs,
handrails and strings intruding into the width by a maximum of 100mm on each side may be
ignored. Rails used for guiding a stair-lift may be ignored, but it should be possible to park the
lift’s chair or carriage in a position that does not obstruct the stair or landing.
step-free
Single steps on escape routes should be prominently marked. A single step on the line of a doorway is acceptable, subject to paragraph 3.107.
storey
NOTES:
1.In assembly buildings (purpose group 5), a gallery is included as a storey, but not if it is a loading gallery, fly gallery, stage grid, lighting bridge, or any gallery provided for similar purposes, or for maintenance and repair.
2.In other purpose group buildings, galleries are not counted as a storey.
3.For the definition of basement, see Appendix A.
Height of top storey measured from upper floor surface of top floor to ground level on lowest side of building
Height of top storey excludes roof-top plant areas and any top storeys consisting exclusively of plant rooms
Volume 1 purpose groups
Purpose for which the building or compartment of a building is intended to be used
Residential(dwellings)
1(a)(1)Flat.
1(b)(2)Dwellinghouse that contains a habitable storey with a floor level a minimum of 4.5m above ground level up to a maximum of 18m.
(3)1(c)(2)(4)Dwellinghouse that does not contain a habitable storey with a floor level a minimum of 4.5m above ground level.
A large dwellinghouse has more than one storey, and at least one storey exceeds 200m2.
A large dwellinghouse of two storeys (excluding basement storeys) should be fitted with a Grade A
Category LD3 fire detection and alarm system, as described in BS 5839-6.
A large dwellinghouse of three or more storeys (excluding basement storeys) should be fitted with
a Grade A Category LD2 fire detection and alarm system as described in BS 5839-6.
A fire detection and alarm system should be installed where either of the
following applies.
a. A new habitable room is provided above or below the ground storey.
b. A new habitable room is provided at the ground storey, without a final exit.
The external envelope of a building should not provide a medium for fire spread if it is likely to be a risk to health or safety. The use of combustible materials for cladding framework, or of combustible thermal insulation as an overcladding or in ventilated cavities, may present such a risk in tall buildings, even though the provisions for external surfaces in Diagram 40 may have been satisfied.
In a building with a storey 18m or more above ground level, insulation material used in ventilated cavities in the external wall construction should be of limited combustibility (see Appendix A). This restriction does not apply to masonry cavity wall construction which complies with Diagram 32 in Section 10. Advice on the use of thermal insulation material is given in the BRE Report Fire performance of external thermal insulation for walls of multi-storey buildings (BR 135, 1988).
All firefighting shafts should have fire mains with outlet connections and valves at every storey.
To assist the fire service to identify each floor in a block of flats with a top storey more than 11m above ground level (see Diagram D6), floor identification signs and flat indicator signs should be provided.
In blocks of flats (purpose group 1(a)) with a top storey over 18m above ground level (see Diagram D6 in Appendix D) an evacuation alert system should be provided in accordance with BS 8629.
Buildings in which firefighting shafts should be provided,
showing which storeys need to be served >18m >10m
a. Any building The upper storeys in any building with a storey more than 18m above fire service vehicle access level
b. Any building The basement storeys in any building with a basement more than 10m below fire service vehicle access level
c. Any building The basement storey(s) in any building with two or more basements each exceeding 900m2
Fire service vehicle access level
Two or more basement storeys each exceeding 900m2
Extent of firefighting Extent of firefighting lift stair
NOTES:
1.Height excludes any top storey(s) consisting exclusively of plant rooms.
2.Firefighting shafts should serve all floors through which they pass.
See para 15.2
A building with basement storeys should have firefighting shafts in accordance with the following.
a. There is a basement more than 10m below the fire and rescue service vehicle access level. The firefighting shafts should contain firefighting lifts.
b. There are two or more basement storeys, each with a minimum area of 900m2. The firefighting shafts do not need to include firefighting lifts.
The building’s height and size determine whether firefighting shafts also serve upper storeys.
Firefighting shafts should serve all storeys through which they pass.
In buildings where a firefighting shaft is required, a minimum of two firefighting shafts should be provided in either of the following situations.
a. A building that has both of the following.
i. A storey with a floor area of 900m2 or more.
ii. A storey 18m or more above the fire and rescue service vehicle access level.
b. A building with a basement storey which is more than 900m2.
If basement storeys are fitted with a sprinkler system in accordance with Appendix E, a mechanical smoke extraction system may be provided as an alternative to natural venting. Sprinklers do not need to be installed on the other storeys unless needed for other reasons.
Car parks are not normally expected to be fitted with sprinklers (see Section 11 of Approved Document B Volume 2).
Natural smoke outlet shafts should be separated from each other using construction of class A1 rating and fire resistance at least equal to that of the storeys they serve, where the shafts are either of the following.
a. From different compartments of the same basement storey.
b. From different basement storeys.
The combined clear cross-sectional area of all smoke outlets should be a minimum of 1/40 of the area of the floor of the storey they serve.
See paras 2.1 to 2.6
Single storey dwellinghouse(see paragraph 2.1)
Dwellinghouse with one storey more than 4.5m above ground level(see paragraph 2.5)
Dwellinghouse with two or more storeys more than 4.5m above ground level(see paragraph 2.6)
Where a new storey is added through conversion to create a storey above 4.5m, both of the following should apply.
a. The full extent of the escape route should be addressed.
b. Fire resisting doors (minimum E 20) and partitions (minimum REI 30) should be provided, including upgrading the existing doors where necessary.
NOTE: Where the layout is open plan, new partitions should be provided to enclose the escape route (Diagram 2.2).
An alternative approach to that described in paragraph 2.21 would be to comply with all of the following.
a. Provide sprinkler protection to the open-plan areas.
b. Provide a fire resisting partition (minimum REI 30) and door (minimum E 20) to separate the ground storey from the upper storeys. The door should allow occupants of the loft room access to a first storey escape window.
c. Separate cooking facilities from the open-plan area with fire resisting construction (minimum REI 30).
See para 2.5
Alternative cavity barrier arrangements in roof space over protected stairway in a house with a storey more than 4.5m above ground level
See Diagram 2.1c. The dwellinghouse should have either of the following. Cavity barriers or a fire resisting ceiling (minimum EI 30) should be provided above a protected stairway enclosure (Diagram 2.3). b. Alternative escape route – a top storey separated from lower storeys by fire resisting construction (minimum REI 30) and with an alternative escape route leading to its own final exit.
a. Protected stairway – a stair separated by fire resisting construction (minimum REI 30) at all storeys, that complies with one of the following.
i. Extends to a final exit (Diagram 2.2a).
ii. Gives access to a minimum of two ground level final exits that are separated from each other by fire resisting construction (minimum REI 30) and fire doorsets (minimum E 20) (Diagram 2.2b).
See Diagram 2.1d. In addition to meeting the provisions in paragraph 2.5, the dwellinghouse should comply with either of the following.
a. Provide an alternative escape route from each storey more than 7.5m above ground level. At the first storey above 7.5m, the protected stairway should be separated from the lower storeys by fire resisting construction (minimum REI 30) if the alternative escape route is accessed via either of the following.
i. The protected stairway to an upper storey.
ii. A landing within the protected stairway enclosure to an alternative escape route on the same storey. The protected stairway at or about 7.5m above ground level should be separated from the lower storeys or levels by fire resisting construction (see Diagram 2.4).
b. Provide a sprinkler system throughout, designed and installed in accordance with BS 9251.
A passenger lift serving any storey more than 4.5m above ground level should be in either of the following.
a. The enclosure to the protected stairway, as described in paragraph 2.5.
b. A fire resisting lift shaft (minimum REI 30).
NOTES:
1. If travel distance is measured to a stair lobby, the lobby must not provide direct access to any storage room, flat or other space containing a fire hazard.
2. In the case of a small single stair building in accordance with Diagram 3.9, this is reduced to 4.5m.
3. Does not apply if all flats on a storey have independent alternative means of escape.
4. Sheltered housing may require reduced maximum travel distances.
A multi-storey flat with an independent external entrance at ground level is similar to a dwellinghouse and means of escape should be planned on the basis of Section 2, depending on the height of the top storey above ground level.
When multi-storey flats do not have their own external entrance at ground level, adopt one of the following approaches.
a. Approach 1 – provide at least one alternative exit from each habitable room that is not on the entrance storey of the flat (Diagram 3.5 and paragraph 3.22).
b. Approach 2 – provide at least one alternative exit from each storey that is not the entrance storey of the flat. All habitable rooms should have direct access to a protected landing (Diagram 3.6 and paragraph 3.22).
Approach 3 – provide a protected stairway plus a sprinkler system in accordance with Appendix E (smoke alarms should also be provided in accordance with Section 1).
d. Approach 4 – if the vertical distance between the entrance storey of the flat and any of the storeys above or below does not exceed 7.5m, provide all of the following.
i. A protected stairway.
ii. Additional smoke alarms in all habitable rooms.
iii. A heat alarm in any kitchen.
For some low rise buildings, the provisions in paragraphs 3.26 and 3.27 may be modified and the use of a single stair, protected in accordance with Diagram 3.9, may be permitted where all of the following apply.
a. The top storey of the building is a maximum of 11m above ground level.
b. No more than three storeys are above the ground storey.
c. The stair does not connect to a covered car park, unless the car park is open sided (as defined in Section 11 of Approved Document B Volume 2).
d. The stair does not serve offices, stores or other ancillary accommodation. If it does, they should be separated from the stair by a protected lobby or protected corridor (minimum REI 30) with a minimum 0.4m2 of permanent ventilation, or be protected from the ingress of smoke by a mechanical smoke control system.
NOTE: For refuse chutes and storage see paragraphs 3.55 to 3.58.
e. Either of the following is provided for the fire and rescue service.
i. A high-level openable vent with a free area of at least 1m2 at each storey.
ii. A single openable vent with a free area of at least 1m2 at the head of the stair, operable remotely at the fire and rescue service access level.
Where a storey or part of a building has multiple escape routes available, one may be over a flat roof that complies with all of the following.
a. It should be part of the same building from which escape is being made.
b. The route across the roof should lead to a storey exit or external escape route.
c. The part of the roof (including its supporting structure) forming the escape route, and any opening within 3m of the escape route, should be of fire resisting construction (minimum REI 30).
d. The route should be clearly defined and guarded by walls and/or protective barriers to protect against falling.
Where a storey or part of a building has multiple escape routes available, one may be over a flat roof that complies with all of the following.
d. The route should be clearly defined and guarded by walls and/or protective barriers to protect against falling.
Common corridors should be protected corridors. The wall between each flat and the corridor should be a compartment wall (minimum REI 30 where the top storey is up to 5m above ground level, otherwise REI 60).
Ancillary accommodation should not be located in, or entered from, a protected lobby or protected corridor forming the only common escape route on that storey.
In mixed use buildings, separate means of escape should be provided from any storeys or parts of storeys used for the ‘residential’ or ‘assembly and recreation’ purpose groups (purpose groups 1, 2 and 5), other than in the case of certain small buildings or buildings in which the residential accommodation is ancillary (see paragraphs 3.76 and 3.77)
Smoke vents should comply with one of the following.
a. They should be located on an external wall with minimum free area of 1.5m2.
b. They should discharge into a vertical smoke shaft, closed at the base, that meets all of the following criteria.
i. The shaft should conform to the following conditions.
• Have a minimum cross-sectional area of 1.5m2 (minimum dimension 0.85m in any direction).
• Open at roof level, minimum 0.5m above any surrounding structures within 2m of it horizontally.
• Extend a minimum of 2.5m above the ceiling of the highest storey served by the shaft.
ii. The free area of all the following vents should be a minimum of 1m2 in the following places.
• From the corridor or lobby into the shaft.
• At the opening at the head of the shaft.
• At all internal locations within the shaft (e.g. safety grilles).
iii. The smoke shaft should be constructed from a class A1 material. All vents should either be a smoke leakage (Sa) rated fire doorset (see Appendix C, Table C1, item 2.e for minimum fire resistance) or fitted with a smoke control damper achieving the same period of fire resistance and designed to operate as described below. The shaft should be vertical from base to head, with a maximum of 4m at a maximum inclined angle of 30 degrees.
iv. If smoke is detected in the common corridor or lobby, both of the following should occur.
• Simultaneous opening of vents on the storey where the fire is located, at the top of the smoke shaft and to the stair.
• Vents from the corridors or lobbies on all other storeys should remain closed, even if smoke is subsequently detected on storeys other than where the fire is located.
A vent to the outside with a minimum free area of 1m2 should be provided from the top storey of the stair.
In single stair buildings, smoke vents on the storey where the fire is initiated, and the vent at the head of the stair, should be activated by smoke detectors in the common parts.
In buildings with more than one stair, smoke vents may be activated manually. The control system should open the vent at the head of the stair before, or at the same time as, the vent on the storey where the fire is located. Smoke detection is not required for ventilation purposes in this instance.
Refuse chutes and rooms for storing refuse should meet both of the following conditions.
a. Be separated from other parts of the building by fire resisting construction (minimum REI 30 in buildings with a top storey up to 5m above ground level; otherwise REI 60).
b. Not be situated within a protected stairway or protected lobby.
See para 3.21
NOTE: This only applies where at least one storey is more than 4.5m above ground level.
Fire doorset
Fire resisting stair enclosure(minimum REI 30)
Alternative exit
Section 7 provides guidance on avoiding the spread of fire between storeys. For a stair that is also a firefighting stair, guidance in Section 15 should be followed.
See paras 3.27 and 3.36
NOTES:
1. The arrangements shown also apply to the top storey.
2. See Diagram 3.9 for small single stair buildings.
3. All doors shown are fire doorsets.
4. Where travel distance is measured to a stair lobby, the lobby must not provide direct access to any storage room, flat or other space containing a potential fire hazard.
5. For further guidance on the fire rating of the fire doorsets from the corridor to the flat and/or stairway refer to Appendix C ,Table C1.
F Flat
Shaded areas indicate zones where ventilation should be provided in accordance with paragraphs 3.50 to 3.53(An external wall vent or smoke shaft located anywhere in the shaded area)
See paras 3.27 and 3.36
NOTES:
1. The arrangements shown also apply to the top storey.
2. See Diagram 3.9 for small single stair buildings.
3. All doors shown are fire doorsets.
4. Where travel distance is measured to a stair lobby, the lobby must not provide direct access to any storage room, flat or other space containing a potential fire hazard.
5. For further guidance on the fire rating of the fire doorsets from the corridor to the flat and/or stairway refer to Appendix C ,Table C1.
F Flat
Shaded areas indicate zones where ventilation should be provided in accordance with paragraphs 3.50 to 3.53(An external wall vent or smoke shaft located anywhere in the shaded area)
If a building does not meet the criteria of paragraph 3.28, an escape stair forming part of the only escape route from an upper storey should not continue down to serve a basement storey. The basement storey should be served by a separate escape stair.
Where multiple escape stairs serve the upper storeys, only one needs to end at ground level. Other stairs may connect with the basement storeys if there is a protected lobby or a protected corridor between the stairs and accommodation at each basement level.
In buildings with a maximum of three storeys above the ground storey, stairs may serve both flats and other occupancies, provided that the stairs are separated from each occupancy by protected lobbies (minimum REI 30) at each storey.
In buildings with more than three storeys above the ground storey, stairs may serve the flats and other occupancies if all of the following apply.
a. The flat is ancillary to the main use of the building.
b. The flat has an independent alternative escape route.
c. The stair is separated from occupancies on lower storeys by a protected lobby (minimum REI 30) at each of those storeys.
d. The stair enclosure has at least the same standard of fire resistance as the structural elements of the building (see Appendix B, Table B4); if the stair is a firefighting stair, it should comply with the provisions in Section 15 (see also paragraph 3.60).
e. Any automatic fire detection and alarm system fitted in the main part of the building also covers all flats.
f. Any security measures in any parts of the building do not prevent escape at all material times.
a. CORRIDOR ACCESS WITHOUT DEAD ENDS
b. CORRIDOR ACCESS WITH DEAD ENDS
The central door may be omitted if maximum travel distance is not more than 15m.
1. The arrangements shown also apply to the top storey.
2. For further guidance on the fire rating of the fire doorsets from the corridor to the flat and/or stairway refer to Appendix C ,Table C1.
Fire doorset provided in accordance with paragraphs 3.50 to 3.53(An external wall vent or smoke shaft located anywhere in the shaded area)
See paras 3.27 and 3.36
a. SMALL SINGLE STAIR BUILDING
*If smoke control is provided in the lobby, the travel distance can be increased to 7.5m maximum(see Diagram 3.7, example b).
b. SMALL SINGLE STAIR BUILDING WITH NO MORE THAN TWO FLATS PER STOREY
The door between stair and lobby should be free from security fastenings.
If the flats have protected entrance halls, the lobby between the common stair and flat entrance is not essential.
NOTES:
1. The arrangements shown also apply to the top storey.
2. If the travel distance across the lobby in diagram (a) exceeds 4.5m, Diagram 3.7 applies.
3. Where,in Diagram (b), the lobby between the common stair and the dwelling is omitted in smal lsingle stair buildings, an automatic opening vent with a free area of at least 1m2 is required at the top of the stair,which is operated automatically on detection of smoke at any storey in the stair.
4. For further guidance on the fire rating of the fire doorsets from the corridor to the flat and/or stairway refer to Appendix C, Table C1.
Fire resisting construction
Openable vent at high level for fire service use (1.0m2 minimum free area); see paragraph 3.28eSee para 3.28
Diagram 3.9
Where adding an additional storey to a two storey single family dwellinghouse, new floors should have a minimum REI 30 fire resistance. Any floor forming part of the enclosure to the circulation space between the loft conversion and the final exit should achieve a minimum rating of REI 30.
The existing first-storey construction should have a minimum rating of R 30. The fire performance may be reduced for integrity and insulation, when both of the following conditions are met.
a. Only one storey is added, containing a maximum of two habitable rooms.
b. The new storey has a maximum total area of 50m2.
In a converted building with a maximum of three storeys, a minimum REI 30 fire resistance could be accepted for elements of structure if the means of escape conform to the provisions of Section 3.
In a converted building with four or more storeys, the full standard of fire resistance given in Appendix B is necessary.
All of the following should be provided as compartment walls and compartment floors and should have, as a minimum, the fire resistance given in Appendix B, Table B3.
a. Any floor (unless it is within a flat, i.e. between one storey and another within one individual dwelling).
b. Any wall separating a flat from another part of the building.
c. Any wall enclosing a refuse storage chamber.
d. Any wall common to two or more buildings.
Compartment walls not described in paragraphs 7.8 and 7.9 should run the full height of the storey in which they are situated.
Compartment walls in a top storey beneath a roof should be continued through the roof space.
A protected shaft conveying piped flammable gas should be ventilated direct to the outside air, by ventilation openings at high and low level in the shaft.
Any extension of the storey floor into the protected shaft should not compromise the free movement of air throughout the entire length of the shaft.
Guidance on shafts conveying piped flammable gas, including the size of ventilation openings, is given in BS 8313.
Blocks of flats with a top storey more than 11m above ground level (see Diagram D6) should be fitted with a sprinkler system throughout the building in accordance with Appendix E.
NOTE: Sprinklers should be provided within the individual flats, they do not need to be provided in the common areas such as stairs, corridors or landings when these areas are fire sterile.
If the fire resisting construction of a protected escape route is either of the following.
a. Not carried to full storey height.
b. At the top storey, not carried to the underside of the roof covering.
Then the cavity above or below the fire resisting construction should be either of the following.
i. Fitted with cavity barriers on the line of the enclosure.
ii. For cavities above the fire resisting construction, enclosed on the lower side by a fire resisting ceiling (minimum EI 30) that extends throughout the building, compartment or separated part (see Diagram 8.3).
For the purposes of this paragraph, the ground storey of a building that has one or more basement storeys and no upper storeys may be considered as a single storey building. The fire resistance of the basement storeys should be that specified for basements.
The number of occupants of a room, storey, building or part of a building is either of the following.
a. The maximum number of people it is designed to hold.
b. In buildings other than dwellings, the number of people calculated by dividing the area of
a room or storey(s) (m2) by a floor space factor (m2 per person) such as given in Table D1 for
guidance.
storey exit
In buildings designed for phased evacuation or progressive horizontal evacuation, if the lift well is not within the enclosures of a protected stairway, its entrance should be separated at every storey by a protected lobby (minimum REI 30).
If a lift delivers into a protected corridor or protected lobby serving sleeping accommodation and also serves a storey containing a high fire risk (such as a kitchen, communal areas, stores, etc.) then the lift should be separated from the high fire risk area(s) by a protected lobby or protected corridor (minimum REI 30).
Final exits should not present a barrier for disabled people. Where the route to a final exit does not include stairs, a level threshold and, where necessary, a ramp should be provided.
Final exit locations should be clearly visible and recognisable.
Final exits should avoid outlets of basement smoke vents and openings to transformer chambers, refuse chambers, boiler rooms and similar risks.
When multi-storey flats do not have their own external entrance at ground level, adopt one of the following approaches.
a. Approach 1 – provide at least one alternative exit from each habitable room that is not on the entrance storey of the flat (Diagram 3.5 and paragraph 3.22).
b. Approach 2 – provide at least one alternative exit from each storey that is not the entrance storey of the flat. All habitable rooms should have direct access to a protected landing (Diagram 3.6 and paragraph 3.22).
Approach 3 – provide a protected stairway plus a sprinkler system in accordance with Appendix E (smoke alarms should also be provided in accordance with Section 1).
d. Approach 4 – if the vertical distance between the entrance storey of the flat and any of the storeys above or below does not exceed 7.5m, provide all of the following.
i. A protected stairway.
ii. Additional smoke alarms in all habitable rooms.
iii. A heat alarm in any kitchen.
Divide a common corridor connecting two or more storey exits with a fire doorset fitted with a self-closing device (minimum E 30 Sa). See Diagram 3.8. Associated screens should be fire resisting. Site doors so that smoke does not affect access to more than one stair.
Single steps on escape routes should be prominently marked. A single step on the line of a doorway is acceptable, subject to paragraph 3.107.
The door of any doorway or exit should be hung to open in the direction of escape whenever reasonably practicable. It should always be hung to open in the direction of escape if more than 60 people might be expected to use it during a fire.
structures
In the Secretary of State’s view, requirement B3 is met by achieving all of the following.
a. For defined periods, loadbearing elements of structure withstand the effects of fire without
loss of stability.
b. Compartmentation of buildings by fire resisting construction elements.
c. Automatic fire suppression is provided where it is necessary.
d. Protection of openings in fire-separating elements to maintain continuity of the fire separation.
e. Inhibition of the unseen spread of fire and smoke in cavities, in order to reduce the risk of
structural failure and spread of fire and smoke, where they pose a threat to the safety of people
in and around the building.
The extent to which any of these measures are necessary is dependent on the use of the building
and, in some cases, its size, and on the location of the elements of construction.
‘Roof covering’ describes one or more layers of material, but not the roof structure as a whole.
Any flexible membrane covering a structure, other than an air-supported structure, should comply with Appendix A of BS 7157.
Guidance on the use of PTFE-based materials for tension-membrane roofs and structures is given in the BRE report BR 274.
If one element of structure supports or stabilises another, as a minimum the supporting element should have the same fire resistance as the other element.
The following are excluded from the definition of ‘element of structure’.
a. A structure that supports only a roof, unless either of the following applies.
i. The roof performs the function of a floor, such as a roof terrace, or as a means of escape.
ii. The structure is essential for the stability of an external wall that needs to be fire resisting (e.g. to achieve compartmentation or for the purposes of preventing fire spread between buildings).
b. The lowest floor of the building.
c. External walls, such as curtain walls or other forms of cladding, which transmit only self weight and wind loads and do not transmit floor load.
NOTE: In some cases, structural members within a roof may be essential for the structural stability system of the building. In these cases, the structural members in the roof do not just support a roof and must demonstrate the relevant fire resistance for the building as required by paragraph 5.2 above.
Elements of structure such as structural frames, beams, columns, loadbearing walls (internal and external), floor structures and gallery structures should have, as a minimum, the fire resistance given in Appendix B, Table B3.
NOTE: If one element of structure supports or stabilises another, as a minimum the supporting element should have the same fire resistance as the other element.
The following are excluded from the definition of ‘element of structure’.
a. A structure that supports only a roof, unless either of the following applies.
i. The roof performs the function of a floor, such as for parking vehicles, or as a means of escape.
ii. The structure is essential for the stability of an external wall that needs to be fire resisting (e.g. to achieve compartmentation or for the purposes of preventing fire spread between buildings).
b. The lowest floor of the building.
c. A platform floor.
d. External walls, such as curtain walls or other forms of cladding, which transmit only self weight and wind loads and do not transmit floor load.
NOTE: In some cases, structural members within a roof may be essential for the structural stability system of the building. In these cases, the structural members in the roof do not just support a roof and must demonstrate the relevant fire resistance for the building as required by the note to paragraph 6.1 above.
In a converted building with a maximum of three storeys, a minimum REI 30 fire resistance could be accepted for elements of structure if the means of escape conform to the provisions of Section 3.
suitable
NOTES:
None of the above designations are suitable for protected stairways.
Polycarbonate and uPVC rooflights that achieve a class C-s3, d2 rating by test (see paragraph 12.7) may be regarded as having a BROOF(t4) classification.
Where Diagram 5.2a or 5.2b applies, rooflights should be a minimum of 1500mm from the compartment wall.
If double-skinned or laminate products have upper and lower surfaces of different materials, the greater distance applies.
1. See also the guidance to requirement B2 in Section 4.
2. The designation of external roof surfaces is explained in Appendix B.
3. Single-skinned rooflight only, in the case of non-thermoplastic material.
4. The rooflight should also meet the provisions of Diagram 12.1.
NOTES:
None of the above designations are suitable for protected stairways.
Polycarbonate and uPVC rooflights that achieve a class C-s3, d2 rating by test (paragraph 12.7) may be regarded as having a BROOF(t4) classification.
Where Diagram 5.2a or 5.2b applies, rooflights should be a minimum of 1500mm from the compartment wall.
If double-skinned or laminate products have upper and lower surfaces of different materials, the greater distance applies.
1. See also the guidance to requirement B2 in section 4.
2. No limit in the case of any space described in 2a, b and c.
3. Single-skinned rooflight only, in the case of non-thermoplastic material.
4. The rooflight should also meet the provisions of diagram 12.1.
Buildings with a storey more than 50m above fire service vehicle access level should be provided with wet fire mains. In all other buildings where fire mains are provided, either wet or dry fire mains are suitable.
If the smoke outlet terminates in a readily accessible position, it may be covered by a panel, stallboard or pavement light that can be broken out or opened. The position of covered smoke outlets should be suitably indicated.
Materials achieving class B-s3, d2 or worse used as a substrate to the roof covering and any timber tiling battens, fully bedded in mortar or other suitable material for the width of the wall (Diagram 5.2b), may extend over the compartment wall in buildings that are a maximum of 15m high.
Openings should be limited to the following.
a. Fire doorsets with a minimum E 30 rating, fitted in accordance with Appendix C.
b. The passage of pipes that follow the provisions in Section 9.
c. The passage of cables or conduits containing one or more cables.
d. Openings fitted with a suitably mounted and appropriate fire damper.
e. Ducts that are either of the following.
i. Fire resisting (minimum E 30).
ii. Fitted with a suitably mounted and appropriate fire damper where they pass through the cavity barrier.
NOTE: For further guidance on openings in cavity barriers see Section 9.
An ES classified fire and smoke damper which is activated by a suitable fire detection system (method 4) may also be used for protected escape routes.
Proprietary, tested fire-stopping and sealing systems are available and may be used. Different materials suit different situations and not all are suitable in every situation.
Further information on generic systems, their suitability for different applications and guidance on test methods, is given in the ASFP Red Book.
supplier
In addition to any other provisions in this section, both of the following conditions should be met.
a. Joints between fire-separating elements should be fire-stopped.
b. Openings through a fire resisting element for pipes, ducts, conduits or cable should be all of the following.
i. As few as possible.
ii. As small as practicable.
iii. Fire-stopped (allowing thermal movement in the case of a pipe or duct).
NOTE: The fire-stopping around fire dampers, fire resisting ducts, fire and smoke dampers and smoke control ducts should be in accordance with the manufacturer or supplier’s installation instructions.
supported wall
a. ANY BUILDING OR COMPARTMENT
Roof covering over this distance to be designated BROOF(t4) rated on deck of material of class A2-s3, d2 or better. Roof covering and deck could be composite structure, e.g. profiled steel cladding.
Fire-stopping to be carried up to underside of roof covering, boarding or slab.
Roof covering to be designated BROOF(t4) rated for at least 1500mm either side of wall.
b. RESIDENTIAL (DWELLINGS) AND RESIDENTIAL (OTHER) A MAXIMUM OF 15M HIGH
Boarding (used as a substrate) or timber tiling battens may be carried over the wall provided that they are fully bedded in mortar (or other no less suitable material) where over the wall.
Thermoplastic insulation materials should not be carried over the wall.
Double-skinned insulated roof sheeting with a thermoplastic core should incorporate a band of material of class A2-s3, d2 at least 300mm wide centred over the wall.
Sarking felt may also be carried over the wall.
If roof support members pass through the wall, fire protection to these members for a distance of 1500mm on either side of the wall may be needed to delay distortion at the junction (see paragraph 5.9).
Double-skinned insulated roof sheeting should incorporate a band of material rated class A2-s3, d2 or better, a minimum of 300mm in width, centred over the wall.
If roof support members pass through the wall, fire protection to these members for a distance of 1500mm on either side of the wall may be needed to delay distortion at the junction (see paragraph 5.9).
Fire-stopping to be carried up to underside of roof covering, e.g. roof tiles.
Section X–X
Roof covering to be designated BROOF(t4) rated for at least this distance.
Roofing battens and sarking felt may be carried over the wall.
Fire-stopping to be carried up to underside of roof covering above and below sarking felt.
NOTES:
1. Fire-stopping should be carried over the full thickness of the wall.
2. Fire-stopping should be extended into any eaves.
3. The compartment wall does not necessarily need to be constructed of masonry.
c. ANY BUILDING OR COMPARTMENT
The wall should be extended up through the roof for a height of at least 375mm above the top surface of the adjoining roof covering.
Where there is a height difference of at least 375mm between two roofs or where the roof coverings on either side of the wall are BROOF(t4) rated, the height of the upstand/parapet wall above the highest roof may be reduced to 200mm.
See paras 5.12 to 5.15
The following guidance should be used when applying the fire resistance standards in Table B4.
a. If one element of structure supports or carries or gives stability to another, the fire resistance
of the supporting element should be no less than the minimum period of fire resistance for the
other element (whether that other element is loadbearing or not). In some circumstances, it
may be reasonable to vary this principle, for example:
i. if the supporting structure is in the open air and is not likely to be affected by the fire in
the building
ii. if the supporting structure is in a different compartment, with a fire-separating element
(that has the higher standard of fire resistance) between the supporting and the separated
structure
iii. if a plant room on the roof needs greater fire resistance than the elements of structure
that support it.
b. If an element of structure forms part of more than one building or compartment, that element
should be constructed to the standard of the higher of the relevant provisions.
c. If, due to the slope of the ground, one side of a basement is open at ground level (allowing
smoke to vent and providing access for firefighting) for elements of structure in that storey
it may be appropriate to adopt the standard of fire resistance that applies to above-ground
structures.
d. Although most elements of structure in a single storey building may not need fire resistance,
fire resistance is needed if one of the following applies to the element.
i. It is part of, or supports, an external wall, and there is provision in the guidance on
requirement B4 to limit the extent of openings and other unprotected areas in the wall.
ii. It is part of, or supports, a compartment wall, including a wall that is common to two or
more buildings.
iii. It supports a gallery.
suspended ceiling
see Table B4
See Table C1
See Appendix C
NOTES:
1. BS EN 13501-2 Classification using data from fire resistance tests, excluding ventilation services.BS EN 13501-3
Classification using data from fire resistance tests on products and elements used in building service installations: fire resisting ducts and fire dampers. BS EN 13501-4 Classification using data from fire resistance tests on components of smoke control systems.
In the European classification:
‘R’ is the resistance to fire in terms of loadbearing capacity.
‘E’ is the resistance to fire in terms of integrity.
‘I’ is the resistance to fire in terms of insulation.
The national classifications do not automatically equate with the alternative classifications in the European column, therefore products cannot typically assume a European class unless they have been tested accordingly.
2. BS 476-20 for general principles,BS 476-21 for loadbearing elements,BS 476-22 for non-loadbearing elements,BS 476-23 for fire-protecting suspended ceilings and BS 476-24 for ventilation ducts.
3. Applies to loadbearing elements only (see paragraph B19).
4. Guidance on increasing the fire resistance of existing timber floors is given in BRE Digest 208.
5. Only if a suspended ceiling meets the appropriate provisions should it be relied on to add to the fire resistance of the floor.
6. Such walls may contain areas that do not need to be fire resisting (unprotected areas). See Section 11.
7. Unless needed as part of a wall in item 5a or 5b.
8. Except for any limitations on uninsulated glazed elements given in Table B5.
Insulating core panels consist of an inner core of insulation sandwiched between, and bonded to, a membrane, such as galvanised steel or aluminium.
Where they are used internally they can present particular problems with regard to fire spread and should meet all of the following conditions.
a. Panels should be sealed to prevent exposure of the core to a fire. This includes at joints and where services penetrate the panel.
b. In high fire risk areas, such as kitchens, places of special fire hazard, or in proximity to where hot works occur, only class A1 cored panels should be used.
c. Fixing systems for all panels should be designed to take account of the potential for the panel to delaminate. For instance, where panels are used to form a suspended ceiling, the fixing should pass through the panel and support it from the lower face.
Guidance on the control of flame spread is given in the following sections.
a. Stairs and landings: Sections 2 and 3 (escape stairs) and Section 15 (firefighting shafts).
b. Exposed surfaces above fire-protecting suspended ceilings: Section 8.
c. Enclosures to above-ground drainage system pipes: Section 9.
The following paragraphs apply to lighting diffusers forming part of a ceiling. Diffusers may be part of a luminaire or used below sources of light. The following paragraphs do not apply to diffusers of light fittings attached to the soffit of a ceiling or suspended beneath a ceiling (Diagram 4.1).
Diffusers constructed of thermoplastic material may be incorporated in ceilings to rooms and circulation spaces, but not to protected stairways, if both the following conditions are met.
a. Except for the upper surfaces of the thermoplastic panels, wall and ceiling surfaces exposed in the space above the suspended ceiling should comply with paragraph 4.1.
b. Diffusers should be classified as one of the following.
i. TP(a) rigid – no restrictions on their extent.
ii. TP(b) – limited in their extent (see Table 4.2 and Diagram 4.2).
NOTES:
1. Upper and lower surfaces of suspended ceiling, between plastic panels, to comply with paragraph 4.1.
2. No restriction on class D-s3, d2 diffusers or rooflights in small rooms.
3. See note 4 to Table 4.2. 5m²
See Table 4.2
Cavity barriers should be fixed so their performance is unlikely to be made ineffective by any of the following.
a. Movement of the building due to subsidence, shrinkage or temperature change, and movement of the external envelope due to wind.
b. During a fire, collapse of services penetrating the cavity barriers, either by the failure of the supporting system or through degradation of the service itself (e.g. by melting or burning).
c. During a fire, failure of the cavity barrier fixings. (In roof spaces, where cavity barriers are fixed to roof members, there is no expectation of fire resistance from roof members provided for the purpose of support.)
d. During a fire, failure of any material or construction to which cavity barriers abut. (For example, a suspended ceiling that continues over a fire resisting wall or partition collapses, and the cavity barrier fails prematurely because the ceiling was not designed to provide a minimum fire resistance of EI 30.)
Thermoplastic materials used for window glazing, rooflights and lighting diffusers within suspended ceilings do not need to meet the criteria within paragraph B19 onwards, if the guidance to requirements B2 and B4 is followed.
tapered tread
Single steps on escape routes should be prominently marked. A single step on the line of a doorway is acceptable, subject to paragraph 3.107.
testing and commissioning
Separation distance is the minimum distance from the roof, or part of the roof, to the relevant boundary (paragraph 11.4). Table 12.1 sets out separation distances by the type of roof covering and the size and use of the building.
In addition, roof covering products (and/or materials) defined in Commission Decision 2000/553/ EC of 6 September 2000, implementing Council Directive 89/106/EEC, can be considered to fulfil all of the requirements for the performance characteristic ‘external fire performance’ without the need for testing, provided that any national provisions on the design and execution of works are fulfilled, and can be used without restriction.
the management regulations
The aim of this regulation is to ensure that the person responsible for the building has sufficient
information relating to fire safety to enable them to manage the building effectively. The aim of
regulation 38 will be achieved when the person responsible for the building has all the information
to enable them to do all of the following.
a. Understand and implement the fire safety strategy of the building.
b. Maintain any fire safety system provided in the building.
c. Carry out an effective fire risk assessment of the building.
The Building Regulations do not impose any requirements on the management of a building, but do assume that it will be properly managed. This includes, for example, keeping protected escape routes virtually ‘fire sterile’.
Appropriate fire safety design considers the way in which a building will be managed. Any reliance on an unrealistic or unsustainable management regime cannot be considered to have met the requirements of the regulations.
Once the building is in use, the management regime should be maintained and a suitable risk assessment undertaken for any variation in that regime. Failure to take proper management responsibility may result in the prosecution of an employer, building owner or occupier under legislation such as the Regulatory Reform (Fire Safety) Order 2005.
thermal element
Particular attention is drawn to the following points.
a. Membranes used as part of the external wall construction above ground level should achieve a minimum of class B-s3, d0. Roofing membranes do not need to achieve a minimum of class A2-s1, d0 when used as part of a roof connecting to an external wall.
b. Internal linings should comply with the guidance provided in Section 4.
c. Any part of a roof should achieve the minimum performance as detailed in Section 12.
d. As per regulation 7(3), window frames and glass (including laminated glass) are exempted
from regulation 7(2). Window spandrel panels and infill panels must comply with regulation 7(2).
e. Thermal breaks are small elements used as part of the external wall construction to restrict
thermal bridging. There is no minimum performance for these materials. However, they
should not span two compartments and should be limited in size to the minimum required
to restrict the thermal bridging (the principal insulation layer is not to be regarded as a
thermal break).
f. Regulation 7(2) only applies to specified attachments. Shop front signs and similar attachments are
not covered by the requirements of regulation 7(2), although attention is drawn to paragraph 10.21g.
g. While regulation 7(2) applies to materials which become part of an external wall or specified
attachment, consideration should be given to other attachments to the wall which could
impact on the risk of fire spread over the wall.
h. Any material achieving class A1fl or A2fl-s1 in accordance with BS EN 13501-1 is exempted when it
meets both of the following conditions.
i. It forms the top horizontal floor layer of a balcony.
ii. It is provided with an imperforate substrate under it which extends to the full size of the
class A1fl or A2fl-s1 material.
Materials of limited combustibility are defined in TableA7:
a. (National classes) by reference to the method specified in BS 476: Part 11 :1982; or
b. (European classes) in terms of performance when classified as class A2-s3, d2 in accordance with BS EN 13501-1 :2002, Fire classification of construction products and building elements, Part 1 Classification using data from reaction to fire tests when tested to BS EN ISO 1182:2002, Reaction to fire tests for building products -Non-combustibility test or BS EN ISO 1716:2002 Reaction to fire tests for building products -Determination of the gross calorific value and BS EN 13823:2002, Reaction to fire tests for building products - Building products excluding floorings exposed to the thermal attack by a single burning item.
Table A7 also includes composite products (such as plasterboard) which are considered acceptable, and where these are exposed as linings they should also meet any appropriate flame spread rating.
Materials of limited combustibility are defined in Table A7:
a. (National classes) by reference to the method specified in BS476: Part 11:1982; or
b. (European classes) in terms of performance when classified as class A2-s3, d2 in accordance with BS EN 13501-1 :2002, Fire classification of construction products and building elements, Part 1 - Classification using data from reaction to fire tests when tested to BS EN ISO 1182:2002, Reaction to fire tests for building products - Non combustibility test or BS EN ISO 1716:2002 Reaction to fire tests for building products - Determination of the gross calorific value and BS EN 13823:2002, Reaction to fire tests for building products - Building products excluding floorings exposed to the thermal attack by a single burning item.
Table A7 also includes composite products (such as plasterboard) which are considered acceptable and where these are exposed as linings they should also meet any appropriate flame spread rating.
thermoplastic material
Table 12.3 sets the limitations for using thermoplastic materials with a TP(a) rigid or TP(b) (see also Diagram 12.1) classification. The method of classifying thermoplastic materials is given in Appendix B.
Thermoplastic materials that do not meet the classifications in Table 4.1 can be used as described in paragraphs 4.13 to 4.17. No guidance for European fire test performance is currently available, because there is no generally accepted test and classification procedure.
Thermoplastic materials are defined in Appendix B, paragraph B11. Classifications used here are explained in paragraph B13.
Thermoplastic material classified as a TP(a) rigid product may be used to glaze external windows to rooms, but not external windows to circulation spaces. Approved Document K includes guidance on the safety of glazing.
In rooms and circulation spaces other than protected stairways, rooflights may be constructed of thermoplastic material if they comply with both of the following.
a. The lower surface is classified as TP(a) rigid or TP(b).
b. The size and location of the rooflights follow the limits in Table 4.2, Table 12.2 and Table 12.3.
Diffusers constructed of thermoplastic material may be incorporated in ceilings to rooms and circulation spaces, but not to protected stairways, if both the following conditions are met.
a. Except for the upper surfaces of the thermoplastic panels, wall and ceiling surfaces exposed in the space above the suspended ceiling should comply with paragraph 4.1.
b. Diffusers should be classified as one of the following.
i. TP(a) rigid – no restrictions on their extent.
ii. TP(b) – limited in their extent (see Table 4.2 and Diagram 4.2).
a. ANY BUILDING OR COMPARTMENT
Roof covering over this distance to be designated BROOF(t4) rated on deck of material of class A2-s3, d2 or better. Roof covering and deck could be composite structure, e.g. profiled steel cladding.
Fire-stopping to be carried up to underside of roof covering, boarding or slab.
Roof covering to be designated BROOF(t4) rated for at least 1500mm either side of wall.
b. RESIDENTIAL (DWELLINGS) AND RESIDENTIAL (OTHER) A MAXIMUM OF 15M HIGH
Boarding (used as a substrate) or timber tiling battens may be carried over the wall provided that they are fully bedded in mortar (or other no less suitable material) where over the wall.
Thermoplastic insulation materials should not be carried over the wall.
Double-skinned insulated roof sheeting with a thermoplastic core should incorporate a band of material of class A2-s3, d2 at least 300mm wide centred over the wall.
Sarking felt may also be carried over the wall.
If roof support members pass through the wall, fire protection to these members for a distance of 1500mm on either side of the wall may be needed to delay distortion at the junction (see paragraph 5.9).
Double-skinned insulated roof sheeting should incorporate a band of material rated class A2-s3, d2 or better, a minimum of 300mm in width, centred over the wall.
If roof support members pass through the wall, fire protection to these members for a distance of 1500mm on either side of the wall may be needed to delay distortion at the junction (see paragraph 5.9).
Fire-stopping to be carried up to underside of roof covering, e.g. roof tiles.
Section X–X
Roof covering to be designated BROOF(t4) rated for at least this distance.
Roofing battens and sarking felt may be carried over the wall.
Fire-stopping to be carried up to underside of roof covering above and below sarking felt.
NOTES:
1. Fire-stopping should be carried over the full thickness of the wall.
2. Fire-stopping should be extended into any eaves.
3. The compartment wall does not necessarily need to be constructed of masonry.
c. ANY BUILDING OR COMPARTMENT
The wall should be extended up through the roof for a height of at least 375mm above the top surface of the adjoining roof covering.
Where there is a height difference of at least 375mm between two roofs or where the roof coverings on either side of the wall are BROOF(t4) rated, the height of the upstand/parapet wall above the highest roof may be reduced to 200mm.
See paras 5.12 to 5.15
Double-skinned insulated roof sheeting with a thermoplastic core should incorporate a band of material rated class A2-s3, d2 or better, a minimum of 300mm in width, centred over the wall.
Thermoplastic material is any synthetic polymeric material that has a softening point below 200°C if tested to BS EN ISO 306 Method A120. Products formed from these materials cannot always be classified in the normal way. In those circumstances the following approach can be followed.
Thermoplastic materials used for window glazing, rooflights and lighting diffusers within suspended ceilings do not need to meet the criteria within paragraph B19 onwards, if the guidance to requirements B2 and B4 is followed.
For the purposes of requirements B2 and B4, thermoplastic materials should be classified as TP(a)
rigid, TP(a) flexible or TP(b), as follows:
a. TP(a) rigid
i. rigid solid uPVC sheet
ii. solid (as distinct from double- or multi-skinned) polycarbonate sheet a minimum of 3mm
thick
iii. multi-skinned rigid sheet made from uPVC or polycarbonate that has a class 1 rating when
tested to BS 476-7
iv. any other rigid thermoplastic product, a specimen of which (at the thickness of the
product as put on the market), when tested to BS 2782-0 Method 508A, performs so that
both:
• the test flame extinguishes before the first mark
• the duration of flaming or afterglow does not exceed 5 seconds following removal of
the burner.
b. TP(a) flexible
Flexible products a maximum of 1mm thick that comply with the Type C requirements
of BS 5867-2 when tested to BS 5438 Test 2 with the flame applied to the surface of the
specimens for 5, 15, 20 and 30 seconds respectively, but excluding the cleansing procedure; and
c. TP(b)
i. rigid solid polycarbonate sheet products a maximum of 3mm thick, or multi-skinned
polycarbonate sheet products that do not qualify as TP(a) by test
ii. other products which, when a specimen of the material between 1.5 and 3mm thick is
tested in accordance with BS 2782-0 Method 508A, have a maximum rate of burning of
50mm/minute.
NOTE: If it is not possible to cut or machine a 3mm thick specimen from the product, then a 3mm
A thermoplastic material alone when used as a lining to a wall or ceiling cannot be assumed to protect a substrate. The surface rating of both thermoplastic material and substrate must therefore meet the required classification. If, however, the thermoplastic material is fully bonded to a non-thermoplastic substrate, then only the surface rating of the composite needs to meet the required classification.
total floor area
Where a building or compartment has more than one use, it is appropriate to assign each different use to its own purpose group in the following situations.
a. If the ancillary use is a flat.
b. If both of the following apply.
i. The building or compartment has an area of more than 280m2.
ii. The ancillary use relates to an area that is more than one-fifth of the total floor area of the building or compartment.
c. In ‘shop and commercial’ (purpose group 4) buildings or compartments, if the ancillary use is storage and both of the following apply.
i. The building or compartment has an area of more than 280m2.
ii. The storage area comprises more than one-third of the total floor area of the building or compartment.
Parts of walls in rooms may be of lower performance than stated in Table 4.1, but no worse than class D-s3, d2. In any one room, the total area of lower performance wall lining should be less than an area equivalent to half of the room’s floor area, up to a maximum of 20m2 of wall lining.
total useful floor area
Where a building or compartment has more than one use, it is appropriate to assign each different use to its own purpose group in the following situations.
a. If the ancillary use is a flat.
b. If both of the following apply.
i. The building or compartment has an area of more than 280m2.
ii. The ancillary use relates to an area that is more than one-fifth of the total floor area of the building or compartment.
c. In ‘shop and commercial’ (purpose group 4) buildings or compartments, if the ancillary use is storage and both of the following apply.
i. The building or compartment has an area of more than 280m2.
ii. The storage area comprises more than one-third of the total floor area of the building or compartment.
Where a building or compartment has more than one use, it is appropriate to assign each different use to its own purpose group in the following situations.
a. If the ancillary use is a flat.
b. If both of the following apply.
i. The building or compartment has an area of more than 280m2.
ii. The ancillary use relates to an area that is more than one-fifth of the total floor area of the building or compartment.
c. In ‘shop and commercial’ (purpose group 4) buildings or compartments, if the ancillary use is storage and both of the following apply.
i. The building or compartment has an area of more than 280m2.
ii. The storage area comprises more than one-third of the total floor area of the building or compartment.
People should be able to rapidly leave the area around the building. Direct access to a street, passageway, walkway or open space should be available. The route away from the building should comply with the following.
a. Be well defined.
b. If necessary, have suitable guarding.
People should be able to rapidly leave the area around the building. Direct access to a street, passageway, walkway or open space should be available. The route away from the building should comply with the following.
a. Be well defined.
b. If necessary, have suitable guarding.
traffic route
Single steps on escape routes should be prominently marked. A single step on the line of a doorway is acceptable, subject to paragraph 3.107.
travel distance
NOTES:
1.Hose laying distance should be measured from the fire main outlet along the route suitable for laying hose. If this route is not known, the distance should be taken at two-thirds of the direct distance
2.The fire main outlet should be located according to Section 14.
See para 15.7
Firefighting shafts and protected stairways should be positioned such that every part of each storey more than 18m above the fire and rescue service vehicle access level complies with the maximum distances given in paragraph 15.7. Distances should be measured from the fire main outlet on a route suitable for laying a hose.
NOTE: If the internal layout is not known, the distance should be measured at two-thirds of the direct distance.
NOTES:
1. If travel distance is measured to a stair lobby, the lobby must not provide direct access to any storage room, flat or other space containing a fire hazard.
2. In the case of a small single stair building in accordance with Diagram 3.9, this is reduced to 4.5m.
3. Does not apply if all flats on a storey have independent alternative means of escape.
4. Sheltered housing may require reduced maximum travel distances.
NOTES:
1. If travel distance is measured to a stair lobby, the lobby must not provide direct access to any storage room, flat or other space containing a fire hazard.
2. In the case of a small single stair building in accordance with Diagram 3.9, this is reduced to 4.5m.
3. Does not apply if all flats on a storey have independent alternative means of escape.
4. Sheltered housing may require reduced maximum travel distances.
One of the following approaches should be adopted, observing the inner room restrictions described in paragraphs 3.7 and 3.8.
a. Provide a protected entrance hall (minimum REI 30) serving all habitable rooms that meets the conditions shown in Diagram 3.2.
b. Plan the flat to meet the conditions shown in Diagram 3.3, so that both of the following apply.
i. The travel distance from the flat entrance door to any point in any habitable room is a maximum of 9m.
ii. Cooking facilities are remote from the main entrance door and do not impede the escape route from anywhere in the flat.
c. Provide an alternative exit from the flat complying with paragraph 3.19.
One of the following approaches should be adopted, observing the inner room restrictions described in paragraphs 3.7 and 3.8.
a. Provide a protected entrance hall (minimum REI 30) serving all habitable rooms that meets the conditions shown in Diagram 3.2.
b. Plan the flat to meet the conditions shown in Diagram 3.3, so that both of the following apply.
i. The travel distance from the flat entrance door to any point in any habitable room is a maximum of 9m.
ii. Cooking facilities are remote from the main entrance door and do not impede the escape route from anywhere in the flat.
c. Provide an alternative exit from the flat complying with paragraph 3.19.
For flats serving as a workplace for both occupants and people who do not live on the premises, provide both of the following.
a. A maximum travel distance of 18m between any part of the working area and either of the following.
i. The flat entrance door.
ii. An alternative means of escape that is not a window.
If the travel distance is over 18m, the assumptions in paragraph 3.2 may not be valid. The design should be considered on a case-by-case basis.
b. Escape lighting to windowless accommodation in accordance with BS 5266-1.
For flats serving as a workplace for both occupants and people who do not live on the premises, provide both of the following.
a. A maximum travel distance of 18m between any part of the working area and either of the following.
i. The flat entrance door.
ii. An alternative means of escape that is not a window.
If the travel distance is over 18m, the assumptions in paragraph 3.2 may not be valid. The design should be considered on a case-by-case basis.
b. Escape lighting to windowless accommodation in accordance with BS 5266-1.
From the flat entrance door, a single escape route is acceptable in either of the following cases.
a. The flat is on a storey served by a single common stair and both of the following apply.
i. Every flat is separated from the common stair by a protected lobby or common protected corridor (see Diagram 3.7).
ii. The maximum travel distance in Table 3.1, for escape in one direction only, is not exceeded.
b. The flat is in a dead end of a common corridor served by two (or more) common stairs and the maximum travel distance given in Table 3.1, for escape in one direction only, is not exceeded (Diagram 3.8).
From the flat entrance door, a single escape route is acceptable in either of the following cases.
a. The flat is on a storey served by a single common stair and both of the following apply.
i. Every flat is separated from the common stair by a protected lobby or common protected corridor (see Diagram 3.7).
ii. The maximum travel distance in Table 3.1, for escape in one direction only, is not exceeded.
b. The flat is in a dead end of a common corridor served by two (or more) common stairs and the maximum travel distance given in Table 3.1, for escape in one direction only, is not exceeded (Diagram 3.8).
Escape route travel distances should comply with Table 3.1.
Escape route travel distances should comply with Table 3.1.
See paras 3.27 and 3.36
NOTES:
1. The arrangements shown also apply to the top storey.
2. See Diagram 3.9 for small single stair buildings.
3. All doors shown are fire doorsets.
4. Where travel distance is measured to a stair lobby, the lobby must not provide direct access to any storage room, flat or other space containing a potential fire hazard.
5. For further guidance on the fire rating of the fire doorsets from the corridor to the flat and/or stairway refer to Appendix C ,Table C1.
F Flat
Shaded areas indicate zones where ventilation should be provided in accordance with paragraphs 3.50 to 3.53(An external wall vent or smoke shaft located anywhere in the shaded area)
See paras 3.27 and 3.36
NOTES:
1. The arrangements shown also apply to the top storey.
2. See Diagram 3.9 for small single stair buildings.
3. All doors shown are fire doorsets.
4. Where travel distance is measured to a stair lobby, the lobby must not provide direct access to any storage room, flat or other space containing a potential fire hazard.
5. For further guidance on the fire rating of the fire doorsets from the corridor to the flat and/or stairway refer to Appendix C ,Table C1.
F Flat
Shaded areas indicate zones where ventilation should be provided in accordance with paragraphs 3.50 to 3.53(An external wall vent or smoke shaft located anywhere in the shaded area)
See paras 3.27 and 3.36
NOTES:
1. The arrangements shown also apply to the top storey.
2. See Diagram 3.9 for small single stair buildings.
3. All doors shown are fire doorsets.
4. Where travel distance is measured to a stair lobby, the lobby must not provide direct access to any storage room, flat or other space containing a potential fire hazard.
5. For further guidance on the fire rating of the fire doorsets from the corridor to the flat and/or stairway refer to Appendix C ,Table C1.
F Flat
Shaded areas indicate zones where ventilation should be provided in accordance with paragraphs 3.50 to 3.53(An external wall vent or smoke shaft located anywhere in the shaded area)
See paras 3.27 and 3.36
NOTES:
1. The arrangements shown also apply to the top storey.
2. See Diagram 3.9 for small single stair buildings.
3. All doors shown are fire doorsets.
4. Where travel distance is measured to a stair lobby, the lobby must not provide direct access to any storage room, flat or other space containing a potential fire hazard.
5. For further guidance on the fire rating of the fire doorsets from the corridor to the flat and/or stairway refer to Appendix C ,Table C1.
F Flat
Shaded areas indicate zones where ventilation should be provided in accordance with paragraphs 3.50 to 3.53(An external wall vent or smoke shaft located anywhere in the shaded area)
a. CORRIDOR ACCESS WITHOUT DEAD ENDS
b. CORRIDOR ACCESS WITH DEAD ENDS
The central door may be omitted if maximum travel distance is not more than 15m.
1. The arrangements shown also apply to the top storey.
2. For further guidance on the fire rating of the fire doorsets from the corridor to the flat and/or stairway refer to Appendix C ,Table C1.
Fire doorset provided in accordance with paragraphs 3.50 to 3.53(An external wall vent or smoke shaft located anywhere in the shaded area)
See paras 3.27 and 3.36
a. CORRIDOR ACCESS WITHOUT DEAD ENDS
b. CORRIDOR ACCESS WITH DEAD ENDS
The central door may be omitted if maximum travel distance is not more than 15m.
1. The arrangements shown also apply to the top storey.
2. For further guidance on the fire rating of the fire doorsets from the corridor to the flat and/or stairway refer to Appendix C ,Table C1.
Fire doorset provided in accordance with paragraphs 3.50 to 3.53(An external wall vent or smoke shaft located anywhere in the shaded area)
See paras 3.27 and 3.36
a. SMALL SINGLE STAIR BUILDING
*If smoke control is provided in the lobby, the travel distance can be increased to 7.5m maximum(see Diagram 3.7, example b).
b. SMALL SINGLE STAIR BUILDING WITH NO MORE THAN TWO FLATS PER STOREY
The door between stair and lobby should be free from security fastenings.
If the flats have protected entrance halls, the lobby between the common stair and flat entrance is not essential.
NOTES:
1. The arrangements shown also apply to the top storey.
2. If the travel distance across the lobby in diagram (a) exceeds 4.5m, Diagram 3.7 applies.
3. Where,in Diagram (b), the lobby between the common stair and the dwelling is omitted in smal lsingle stair buildings, an automatic opening vent with a free area of at least 1m2 is required at the top of the stair,which is operated automatically on detection of smoke at any storey in the stair.
4. For further guidance on the fire rating of the fire doorsets from the corridor to the flat and/or stairway refer to Appendix C, Table C1.
Fire resisting construction
Openable vent at high level for fire service use (1.0m2 minimum free area); see paragraph 3.28eSee para 3.28
Diagram 3.9
a. SMALL SINGLE STAIR BUILDING
*If smoke control is provided in the lobby, the travel distance can be increased to 7.5m maximum(see Diagram 3.7, example b).
b. SMALL SINGLE STAIR BUILDING WITH NO MORE THAN TWO FLATS PER STOREY
The door between stair and lobby should be free from security fastenings.
If the flats have protected entrance halls, the lobby between the common stair and flat entrance is not essential.
NOTES:
1. The arrangements shown also apply to the top storey.
2. If the travel distance across the lobby in diagram (a) exceeds 4.5m, Diagram 3.7 applies.
3. Where,in Diagram (b), the lobby between the common stair and the dwelling is omitted in smal lsingle stair buildings, an automatic opening vent with a free area of at least 1m2 is required at the top of the stair,which is operated automatically on detection of smoke at any storey in the stair.
4. For further guidance on the fire rating of the fire doorsets from the corridor to the flat and/or stairway refer to Appendix C, Table C1.
Fire resisting construction
Openable vent at high level for fire service use (1.0m2 minimum free area); see paragraph 3.28eSee para 3.28
Diagram 3.9
Travel distance is measured as the shortest route. Both of the following should be observed.
a. If there is fixed seating or other fixed obstructions, the shortest route is along the centre line of
the seatways and gangways.
b. If the route includes a stair, the shortest route is along the pitch line on the centre line of travel.
Travel distance is measured as the shortest route. Both of the following should be observed.
a. If there is fixed seating or other fixed obstructions, the shortest route is along the centre line of
the seatways and gangways.
b. If the route includes a stair, the shortest route is along the pitch line on the centre line of travel.
ukas
Tests and assessments should be carried out by organisations with the necessary expertise. For NOTE: Standard fire tests do not directly measure fire hazard. They measure or assess the response
example, organisations listed as ‘notified bodies’ in accordance with the European Construction Products Regulation or laboratories accredited by the United Kingdom Accreditation Service (UKAS)
for the relevant test standard can be assumed to have the necessary expertise.
of a material or system to exposure to one or more aspects of fire conditions. Performance in fire
tests is only one of a number of factors that should be taken into account.
united kingdom accreditation service
Tests and assessments should be carried out by organisations with the necessary expertise. For NOTE: Standard fire tests do not directly measure fire hazard. They measure or assess the response
example, organisations listed as ‘notified bodies’ in accordance with the European Construction Products Regulation or laboratories accredited by the United Kingdom Accreditation Service (UKAS)
for the relevant test standard can be assumed to have the necessary expertise.
of a material or system to exposure to one or more aspects of fire conditions. Performance in fire
tests is only one of a number of factors that should be taken into account.
unprotected area
The external envelope of a building should not provide a medium for undue fire spread to
adjacent buildings or be readily ignited by fires in adjacent buildings. This intention can be met by
constructing external walls so that all of the following are satisfied.
a. The risk of ignition by an external source to the outside surface of the building is restricted.
b. The amount of thermal radiation that falls on a neighbouring building from window openings
and other unprotected areas in the building on fire is not enough to start a fire in the other
building.
c. Flame spread over the roof and/or fire penetration from external sources through the roof is
restricted.
The extent to which this is necessary depends on the use of the building and its position in relation
to adjacent buildings and therefore the site boundary.
see Table B4
See Table C1
See Appendix C
NOTES:
1. BS EN 13501-2 Classification using data from fire resistance tests, excluding ventilation services.BS EN 13501-3
Classification using data from fire resistance tests on products and elements used in building service installations: fire resisting ducts and fire dampers. BS EN 13501-4 Classification using data from fire resistance tests on components of smoke control systems.
In the European classification:
‘R’ is the resistance to fire in terms of loadbearing capacity.
‘E’ is the resistance to fire in terms of integrity.
‘I’ is the resistance to fire in terms of insulation.
The national classifications do not automatically equate with the alternative classifications in the European column, therefore products cannot typically assume a European class unless they have been tested accordingly.
2. BS 476-20 for general principles,BS 476-21 for loadbearing elements,BS 476-22 for non-loadbearing elements,BS 476-23 for fire-protecting suspended ceilings and BS 476-24 for ventilation ducts.
3. Applies to loadbearing elements only (see paragraph B19).
4. Guidance on increasing the fire resistance of existing timber floors is given in BRE Digest 208.
5. Only if a suspended ceiling meets the appropriate provisions should it be relied on to add to the fire resistance of the floor.
6. Such walls may contain areas that do not need to be fire resisting (unprotected areas). See Section 11.
7. Unless needed as part of a wall in item 5a or 5b.
8. Except for any limitations on uninsulated glazed elements given in Table B5.
Table 10.1 Reaction to fire performance of external surface of walls
‘Relevant buildings’ as defined in regulation 7(4) (see paragraph 10.10)
NOTES:
In addition to the requirements within this table, buildings with a top occupied storey above 18m should also meet the provisions of paragraph 10.6.
In all cases, the advice in paragraph 10.4 should be followed.
1. The restrictions for these buildings apply to all the materials used in the external wall and specified attachments (see paragraphs 10.9 to 10.12 for further guidance).
2. Profiled or flat steel sheet at least 0.5 mm thick with an organic coating of no more than 0.2mm thickness is also acceptable.
3. Timber cladding at least 9mm thick is also acceptable.
4. 10m is measured from the top surface of the roof.
The external wall of a building should not provide a medium for fire spread if that is likely to be a risk to health and safety. Combustible materials and cavities in external walls and attachments to them can present such a risk, particularly in tall buildings. The guidance in this section is designed to reduce the risk of fire spread as well as the risk of ignition from flames coming from adjacent buildings.
Relevant metal composite materials are defined (in regulation 2(6)(c)) as any panel or sheet, having a thickness of no more than 10mm which is composed of a number of layers two or more of which are made of metal, alloy or metal compound and one or more of which is a substantial layer made of a material having a gross calorific value of more than 35MJ/kg when tested in accordance with BS EN ISO 1716. A substantial layer is defined as a layer which is at least 1mm thick or has a mass per unit area of at least 1kg/m².
External walls and specified attachments are defined in regulation 2(6) and these definitions
include any parts of the external wall as well as balconies, solar panels and solar shading.
Particular attention is drawn to the following points.
a. Membranes used as part of the external wall construction above ground level should achieve a minimum of class B-s3, d0. Roofing membranes do not need to achieve a minimum of class A2-s1, d0 when used as part of a roof connecting to an external wall.
b. Internal linings should comply with the guidance provided in Section 4.
c. Any part of a roof should achieve the minimum performance as detailed in Section 12.
d. As per regulation 7(3), window frames and glass (including laminated glass) are exempted
from regulation 7(2). Window spandrel panels and infill panels must comply with regulation 7(2).
e. Thermal breaks are small elements used as part of the external wall construction to restrict
thermal bridging. There is no minimum performance for these materials. However, they
should not span two compartments and should be limited in size to the minimum required
to restrict the thermal bridging (the principal insulation layer is not to be regarded as a
thermal break).
f. Regulation 7(2) only applies to specified attachments. Shop front signs and similar attachments are
not covered by the requirements of regulation 7(2), although attention is drawn to paragraph 10.21g.
g. While regulation 7(2) applies to materials which become part of an external wall or specified
attachment, consideration should be given to other attachments to the wall which could
impact on the risk of fire spread over the wall.
h. Any material achieving class A1fl or A2fl-s1 in accordance with BS EN 13501-1 is exempted when it
meets both of the following conditions.
i. It forms the top horizontal floor layer of a balcony.
ii. It is provided with an imperforate substrate under it which extends to the full size of the
class A1fl or A2fl-s1 material.
The external surfaces (i.e. outermost external material) of external walls should comply with the provisions in Table 10.1. The provisions in Table 10.1 apply to each wall individually in relation to its proximity to the relevant boundary.
In a building with a storey 18m or more in height (see Diagram D6 in Appendix D) any insulation product, filler material (such as the core materials of metal composite panels, sandwich panels and window spandrel panels but not including gaskets, sealants and similar) etc. used in the construction of an external wall should be class A2-s3, d2 or better (see Appendix B). This restriction does not apply to masonry cavity wall construction which complies with Diagram 8.2 in Section 8. Where regulation 7(2) applies, that regulation prevails over all the provisions in this paragraph.
In buildings that include a ‘residential’ purpose (purpose groups 1 and 2) with a storey 11m or more in height (see Diagram D6 in Appendix D) any insulation product, filler material (such as the core materials of metal composite panels, sandwich panels and window spandrel panels but not including gaskets, sealants and similar) etc. used in the construction of an external wall should be class A2-s1, d0 or better (see Appendix B). This restriction does not apply to masonry cavity wall construction which complies with Diagram 8.2 in Section 8. Where regulation 7(2) applies, that regulation prevails over all the provisions in this paragraph.
Wall sufficiently distant from relevant boundary to be a 100% unprotected area
Wall on or very close to the relevant boundary: very limited amounts of unprotected area
Wall not on, or not very close to, but not sufficiently far from relevant boundary that it can be a wholly unprotected area
Amount of unprotected area dependent on distance from relevant boundary
See para 11.4
NOTES:
Intermediate values may be obtained by interpolation.
1.The total percentage of unprotected area is found by dividing the total unprotected area by the area of a rectangle that encloses all the unprotected areas, and multiplying the result by 100.
Exclude external walls of stairways in a protected shaft when assessing unprotected areas (see Diagram 11.5).
In an otherwise protected wall, small unprotected areas may be ignored where they meet the conditions in Diagram 11.5.
If a reduced separation distance between buildings, or increased amount of unprotected area, is required, smaller compartments should be considered.
NOTES:
The notional boundary should be set in the area between the two buildings using the following rules:
1. The notional boundary is assumed to exist in the space between the buildings and is positioned so that one of the buildings would comply with the provisions for space separation having regard to the amount of its unprotected area. In practice, if one of the buildings is existing, the position of the boundary will be set by the space separation factors for that building.
2. The siting of the new building, or the second building if both are new, can then be checked to see that it also complies, using the notional boundary as the relevant boundary for the second building.
Notional boundary
Site boundary
Compliance with the provisions for space separation in respect of building A
Compliance with the provisions for space separation in respect of building B
See para 11.5
Area of fire resisting wall with materials more than 1mm thick and with a reaction to fire performance worse than class B-s3, d2 = a x b
Area of wall counted as unprotected area = 0.5a x b
Area of fire resisting wall with materials having a reaction to fire performance better than class B-s3, d2
See para 11.7
The unprotected area of the external wall of a stairway forming a protected shaft may be disregarded for separation distance purposes
Roofs pitched at an angle of less than 70 degrees may be disregarded for separation distance purposes
Represents an unprotected area of not more than 1m2 which may consist of two or more smaller areas within an area of 1000mm X 1000mm
Represents an area of not more than 0.1m2
See para 11.11
Parts of an external wall with less fire resistance than the appropriate amount given in Appendix B, Table B4, are called unprotected areas.
Minimum distance (a) between side of building and relevant boundary (m) Maximum total area of unprotected areas (m2)
See para 11.18
Where a fire resisting external wall has an external surface material that is worse than class B-s3, d2 and is more than 1mm thick, that part of the wall should be classified as an unprotected area equating to half its area (Diagram 11.4).
Unprotected areas should meet the conditions in Diagram 11.5, and the rest of the wall should be fire resisting from both sides.
External surface materials facing the boundary should be class B-s3, d2 or better.
Unprotected areas should not exceed the result given by one of the methods in paragraph 11.16, and the rest of the wall (if any) should be fire resisting but only from the inside of the building.
NOTES:
1.There are restrictions on the use of plastic rooflights in the guidance to requirement B2 in Section 4.
2.Surrounding roof covering to be a material of class A2-s3, d3 or better for at least 3m distance.
3.Where Diagram 5.2a or 5.2b applies, rooflights should be at least 1500mm from the compartment wall.
See paras 12.5 and 12.6
NOTES:
Separation distances do not apply to the boundary between roofs of a pair of semi-detached dwellinghouses and to enclosed/covered walkways. However, see Diagram 5.2 if the roof passes over the top of a compartment wall.
Polycarbonate and uPVC rooflights that achieve a class C-s3, d2 rating by test may be regarded as having a BROOF(t4) designation.
1. The designation of external roof surfaces is explained in Appendix B.
2. Not acceptable on any of the following buildings.
a. Dwellinghouses in terraces of three or more dwellinghouses.
b. Any other buildings with a cubic capacity of more than 1500m3.
3. Acceptable on buildings not listed in (1) if both of the following apply.
a. Part of the roof has a maximum area of 3m2 and is a minimum of 1500mm from any similar part.
b. The roof between the parts is covered with a material rated class A2-s3, d2 or better.
In a building with a storey 18m or more above ground level any insulation product, filler material (not including gaskets, sealants and similar) etc. used in the external wall construction should be of limited combustibility (see Appendix A). This restriction does not apply to masonry cavity wall construction
The highest National product performance classification for lining materials is Class O. This is achieved if a material or the surface of a composite product is either:
a. composed throughout of materials of limited combustibility; or
b. a Class 1 material which has a fire propagation index (I) of not more than 12 and sub-index (i1) of not more than 6.
Note: Class O is not a classification identified in any British Standard test.
The highest national product performance classification for lining materials is Class 0. This is achieved if a material or the surface of a composite product is either:
a. composed throughout of materials of limited combustibility; or
b. a Class 1 material which has a fire propagation index (I) of not more than 12 and sub-index (i1) of not more than 6.
Note: Class O is not a classification identified in any British Standard test.
The external envelope of a building should not provide a medium for fire spread if it is likely to be a risk to health or safety. The use of combustible materials for cladding framework, or of combustible thermal insulation as an overcladding or in ventilated cavities, may present such a risk in tall buildings, even though the provisions for external surfaces in Diagram 40 may have been satisfied.
In a building with a storey 18m or more above ground level, insulation material used in ventilated cavities in the external wall construction should be of limited combustibility (see Appendix A). This restriction does not apply to masonry cavity wall construction which complies with Diagram 32 in Section 10. Advice on the use of thermal insulation material is given in the BRE Report Fire performance of external thermal insulation for walls of multi-storey buildings (BR 135, 1988).
Outlet ducts or shafts, including any bulkheads over them (see Diagram 16.1), should be enclosed in construction of class A1 rating and fire resistance at least equal to that of the element through which they pass.
Natural smoke outlet shafts should be separated from each other using construction of class A1 rating and fire resistance at least equal to that of the storeys they serve, where the shafts are either of the following.
a. From different compartments of the same basement storey.
b. From different basement storeys.
Any external escape stair should meet all of the following conditions (Diagram 2.7).
a. Doors to the stair should be fire resisting (minimum E 30), except for a single exit door from the building to the top landing of a downward-leading external stair.
b. Fire resisting construction (minimum RE 30) is required for the building envelope within the following zones, measured from the flights and landings of the external stair.
i. 1800mm horizontally.
ii. 9m vertically below.
iii. 1100mm above the top landing of the stair (except where the stair leads from basement to ground level).
c. Fire resisting construction (minimum RE 30) should be provided for any part of the building (including doors) within 1800mm of the escape route from the foot of the stair to a place of safety. This does not apply if there are alternative escape routes from the foot of the external escape stair.
d. Stairs more than 6m in height should be protected from adverse weather. Protection should prevent the build-up of snow or ice but does not require full enclosure.
e. Glazing in areas of fire resisting construction should be fixed shut and fire resisting (in terms of integrity, but not insulation) (minimum E 30).
NOTES:
1. This diagram does not apply where the gallery is provided with one of the following:
i. An alternative escape route
ii. An emergency escape window (where the gallery floor is not more than 4.5m above ground level).
2. Any cooking facilities within a room containing a gallery should comply with one of the following conditions:
i. Be enclosed with fire resisting construction
ii. Be remote from the stair to the gallery and positioned such that they do not prejudice escape from the gallery.
See para 2.15
NOTES:
1. This diagram does not apply where the gallery is provided with one of the following:
i. An alternative escape route
ii. An emergency escape window (where the gallery floor is not more than 4.5m above ground level).
2. Any cooking facilities within a room containing a gallery should comply with one of the following conditions:
i. Be enclosed with fire resisting construction
ii. Be remote from the stair to the gallery and positioned such that they do not prejudice escape from the gallery.
See para 3.13
If a protected stairway projects beyond, is recessed from or is in an internal angle of the adjoining external wall of the building, then the minimum distance between an unprotected area of the building enclosure and an unprotected area of the stair enclosure should be 1800mm.
Any external escape stair should meet all of the following conditions (Diagram 3.11).
a. Doors to the stair should be fire resisting (minimum E 30) and be fitted with a self-closing device, except for a single exit door from the building to the top landing of a downward-leading external stair, provided it is the only door onto the landing.
b. Fire resisting construction (minimum RE 30) is required for the building envelope within the following zones, measured from the flights and landings of the external stair.
i. 1800mm above and horizontally.
ii. 9m vertically below.
iii. 1100mm above the top landing of the stair (except where the stair leads from basement to ground level).
c. Fire resisting construction (minimum RE 30) should be provided for any part of the building (including doors) within 1800mm of the escape route from the foot of the stair to a place of safety. This does not apply if there are alternative escape routes from the foot of the external escape stair.
d. Glazing in areas of fire resisting construction should be fixed shut and fire resisting (in terms of integrity but not insulation) (minimum E 30).
e. Stairs more than 6m in height above ground level (e.g. where they are provided above a podium) should be protected from adverse weather. Protection should prevent the build-up of snow or ice but does not require full enclosure.
Fire resistance test criteria are set out in Appendix C. Standards of performance are summarised in Table C1.
If glazed elements in fire resisting enclosures and doors can only meet the required integrity performance, their use is limited. These limitations depend on whether the enclosure forms part of a protected shaft (see Section 7) and the provisions set out in Appendix B, Table B5. If both integrity and insulation performance can be met, there is no restriction in this document on the use or amount of glass.
In general, doors on escape routes (whether or not the doors are fire doorsets) should be either of the following.
a. Not fitted with a lock, latch or bolt fastenings.
b. Fitted only with simple fastenings that are all of the following.
i. Easy to operate; it should be apparent how to undo the fastening.
ii. Operable from the side approached by people escaping.
iii. Operable without a key.
iv. Operable without requiring people to manipulate more than one mechanism.
Doors may be fitted with hardware to allow them to be locked when rooms are empty.
If a secure door is operated by code or combination keypad, swipe or proximity card, biometric data, etc., a security mechanism override should be possible from the side approached by people escaping.
All doors on escape routes should be hung to meet both of the following conditions.
a. Open by a minimum of 90 degrees.
b. Open with a swing that complies with both of the following.
i. Is clear of any change of floor level, other than a threshold or single step on the line of the doorway.
ii. Does not reduce the effective width of any escape route across a landing.
Parts of walls in rooms may be of lower performance than stated in Table 4.1, but no worse than class D-s3, d2. In any one room, the total area of lower performance wall lining should be less than an area equivalent to half of the room’s floor area, up to a maximum of 20m2 of wall lining.
To reduce the risk of fire spreading over the roof from one compartment to another, a 1500mm wide zone of the roof, either side of the wall, should have a covering classified as BROOF(t4), on a substrate or deck of a material rated class A2-s3, d2 or better, as set out in Diagram 5.2a.
Thermoplastic rooflights that, because of paragraph 12.7, are regarded as having a BROOF(t4) classification are not suitable for use in that zone.
Materials achieving class B-s3, d2 or worse used as a substrate to the roof covering and any timber tiling battens, fully bedded in mortar or other suitable material for the width of the wall (Diagram 5.2b), may extend over the compartment wall in buildings that are a maximum of 15m high.
Double-skinned insulated roof sheeting should incorporate a band of material rated class A2-s3, d2 or better, a minimum of 300mm in width, centred over the wall.
a. ANY BUILDING OR COMPARTMENT
Roof covering over this distance to be designated BROOF(t4) rated on deck of material of class A2-s3, d2 or better. Roof covering and deck could be composite structure, e.g. profiled steel cladding.
Fire-stopping to be carried up to underside of roof covering, boarding or slab.
Roof covering to be designated BROOF(t4) rated for at least 1500mm either side of wall.
b. RESIDENTIAL (DWELLINGS) AND RESIDENTIAL (OTHER) A MAXIMUM OF 15M HIGH
Boarding (used as a substrate) or timber tiling battens may be carried over the wall provided that they are fully bedded in mortar (or other no less suitable material) where over the wall.
Thermoplastic insulation materials should not be carried over the wall.
Double-skinned insulated roof sheeting with a thermoplastic core should incorporate a band of material of class A2-s3, d2 at least 300mm wide centred over the wall.
Sarking felt may also be carried over the wall.
If roof support members pass through the wall, fire protection to these members for a distance of 1500mm on either side of the wall may be needed to delay distortion at the junction (see paragraph 5.9).
Double-skinned insulated roof sheeting should incorporate a band of material rated class A2-s3, d2 or better, a minimum of 300mm in width, centred over the wall.
If roof support members pass through the wall, fire protection to these members for a distance of 1500mm on either side of the wall may be needed to delay distortion at the junction (see paragraph 5.9).
Fire-stopping to be carried up to underside of roof covering, e.g. roof tiles.
Section X–X
Roof covering to be designated BROOF(t4) rated for at least this distance.
Roofing battens and sarking felt may be carried over the wall.
Fire-stopping to be carried up to underside of roof covering above and below sarking felt.
NOTES:
1. Fire-stopping should be carried over the full thickness of the wall.
2. Fire-stopping should be extended into any eaves.
3. The compartment wall does not necessarily need to be constructed of masonry.
c. ANY BUILDING OR COMPARTMENT
The wall should be extended up through the roof for a height of at least 375mm above the top surface of the adjoining roof covering.
Where there is a height difference of at least 375mm between two roofs or where the roof coverings on either side of the wall are BROOF(t4) rated, the height of the upstand/parapet wall above the highest roof may be reduced to 200mm.
See paras 5.12 to 5.15
The following are excluded from the definition of ‘element of structure’.
a. A structure that supports only a roof, unless either of the following applies.
i. The roof performs the function of a floor, such as a roof terrace, or as a means of escape.
ii. The structure is essential for the stability of an external wall that needs to be fire resisting (e.g. to achieve compartmentation or for the purposes of preventing fire spread between buildings).
b. The lowest floor of the building.
c. External walls, such as curtain walls or other forms of cladding, which transmit only self weight and wind loads and do not transmit floor load.
NOTE: In some cases, structural members within a roof may be essential for the structural stability system of the building. In these cases, the structural members in the roof do not just support a roof and must demonstrate the relevant fire resistance for the building as required by paragraph 5.2 above.
NOTES:
1. Materials used to close the cavity in this arrangement do not need to achieve a specific performance in relation to fire resistance.
2. Domestic meter cupboards may be installed provided that the following conditions are met:
a. There are no more than two cupboards per dwelling
b. The openings in the outer wall leaf are not bigger than 800X500mm for each cupboard
c. The inner leaf is not penetrated except by a sleeve not more than 80X80mm, which is fire-stopped.
3. Materials achieving class B-s3, d2 or worse may be placed within the cavity.
See para 5.18
At the junction with another compartment wall or an external wall, the fire resistance of the compartmentation should be maintained. Fire-stopping that meets the provisions in paragraphs 9.24 to 9.29 should be provided.
Materials achieving class B-s3, d2 or worse used as a substrate to the roof covering and any timber tiling battens, fully bedded in mortar or other suitable material for the width of the wall (Diagram 5.2b), may extend over the compartment wall in buildings that are both of the following.
a. A maximum of 15m high.
b. In one of the following purpose groups.
i. All residential purpose groups (purpose groups 1 and 2) other than ‘residential (institutional)’ (purpose group 2(a)).
ii. ‘Office’ (purpose group 3).
iii. ‘Assembly and recreation’ (purpose group 5).
Double-skinned insulated roof sheeting with a thermoplastic core should incorporate a band of material rated class A2-s3, d2 or better, a minimum of 300mm in width, centred over the wall.
NOTES:
1. Materials used to close the cavity in this arrangement do not need to achieve a specific performance in relation to fire resistance.
2. Domestic meter cupboards may be installed provided that the following conditions are met:
a. There are no more than two cupboards per dwelling
b. The openings in the outer wall leaf are not bigger than 800X500mm for each cupboard
c. The inner leaf is not penetrated except by a sleeve not more than 80X80mm, which is fire-stopped.
3. Materials achieving class B-s3, d2 or worse may be placed within the cavity.
See para 8.3
Cavity barriers are not required between double-skinned corrugated or profiled insulated roof sheeting, if the sheeting complies with all of the following.
a. The sheeting is rated class A2-s3, d2 or better.
b. Both surfaces of the insulating layer are rated class C-s3, d2 or better.
c. Both surfaces of the insulating layer make contact with the inner and outer skins of cladding (Diagram 8.4).
a. Flue passing through compartment wall or floor
b. Flue built into compartment wall
Flue walls should have a fire resistance of at least one half of that required for the compartment wall or floor and be of class A1construction.
In each case flue walls should have a fire resistance of at least one half of that required for the compartment wall and be of class A1 construction.
See para 9.23
The following guidance should be used when applying the fire resistance standards in Table B4.
a. If one element of structure supports or carries or gives stability to another, the fire resistance
of the supporting element should be no less than the minimum period of fire resistance for the
other element (whether that other element is loadbearing or not). In some circumstances, it
may be reasonable to vary this principle, for example:
i. if the supporting structure is in the open air and is not likely to be affected by the fire in
the building
ii. if the supporting structure is in a different compartment, with a fire-separating element
(that has the higher standard of fire resistance) between the supporting and the separated
structure
iii. if a plant room on the roof needs greater fire resistance than the elements of structure
that support it.
b. If an element of structure forms part of more than one building or compartment, that element
should be constructed to the standard of the higher of the relevant provisions.
c. If, due to the slope of the ground, one side of a basement is open at ground level (allowing
smoke to vent and providing access for firefighting) for elements of structure in that storey
it may be appropriate to adopt the standard of fire resistance that applies to above-ground
structures.
d. Although most elements of structure in a single storey building may not need fire resistance,
fire resistance is needed if one of the following applies to the element.
i. It is part of, or supports, an external wall, and there is provision in the guidance on
requirement B4 to limit the extent of openings and other unprotected areas in the wall.
ii. It is part of, or supports, a compartment wall, including a wall that is common to two or
more buildings.
iii. It supports a gallery.
utility stair
Other than for the purposes of Diagram 5.2, polycarbonate or uPVC rooflights achieving a minimum rating of class C-s3, d2 can be regarded as having a BROOF(t4) classification.
The flights and landings of escape stairs should be constructed of materials achieving class A2-s3, d2 or better in all of the following situations.
a. If the escape stair is the only stair in a building with more than three storeys.
b. If the escape stair is within a basement storey.
c. If the escape stair serves any storey that has a floor level more than 18m above ground or access level.
d. If the escape stair is an external escape stair, except where the stair connects the ground storey or ground level with a floor or flat roof a maximum of 6m above or below ground level.
e. If the escape stair is a firefighting stair.
Materials achieving class B-s3, d2 or worse may be added to the top horizontal surface, except on firefighting stairs.
The flights and landings of escape stairs should be constructed of materials achieving class A2-s3, d2 or better in all of the following situations.
a. If the escape stair is the only stair in a building with more than three storeys.
b. If the escape stair is within a basement storey.
c. If the escape stair serves any storey that has a floor level more than 18m above ground or access level.
d. If the escape stair is an external escape stair, except where the stair connects the ground storey or ground level with a floor or flat roof a maximum of 6m above or below ground level.
e. If the escape stair is a firefighting stair.
Materials achieving class B-s3, d2 or worse may be added to the top horizontal surface, except on firefighting stairs.
Fixed ladders should not be provided as a means of escape for members of the public. They should only be provided where a conventional stair is impractical, such as for access to plant rooms which are not normally occupied.
Fixed ladders should not be provided as a means of escape for members of the public. They should only be provided where a conventional stair is impractical, such as for access to plant rooms which are not normally occupied.
Helical stairs and spiral stairs may form part of an escape route provided they are designed in accordance with BS 5395-2. If they are intended to serve members of the public, stairs should be type E (public) stairs.
Helical stairs and spiral stairs may form part of an escape route provided they are designed in accordance with BS 5395-2. If they are intended to serve members of the public, stairs should be type E (public) stairs.
vehicle
Fire and rescue service vehicles should not have to reverse more than 20m from the end of an access road.
Turning circle, hammerhead or other point at which vehicle can turn
See para 13.4
Buildings without firefighting shafts should be provided with fire mains where fire service vehicle access is not provided in accordance with paragraph 13.2(a). In these cases, the fire mains should be located within the protected stairway enclosure, with a maximum hose distance of 45m from the fire main outlet to the furthest point inside each flat, measured on a route suitable for laying a hose.
Buildings with a storey more than 50m above fire service vehicle access level should be provided with wet fire mains. In all other buildings where fire mains are provided, either wet or dry fire mains are suitable.
Fire service vehicle access to fire mains should be provided as described in paragraphs 13.5 and 13.6.
In low rise buildings without deep basements, access for firefighting personnel is typically achieved by providing measures for fire service vehicle access in Section 13 and means of escape.
A building with a storey more than 18m above the fire and rescue service vehicle access level should have one or more firefighting shafts, each containing a firefighting lift (Diagram 15.1). The number and location of firefighting shafts should comply with paragraphs 15.4 to 15.7. Firefighting shafts are not required to serve a basement that is not large or deep enough to need one (see paragraph 15.3 and Diagram 15.2).
Buildings in which firefighting shafts should be provided,
showing which storeys need to be served >18m >10m
a. Any building The upper storeys in any building with a storey more than 18m above fire service vehicle access level
b. Any building The basement storeys in any building with a basement more than 10m below fire service vehicle access level
c. Any building The basement storey(s) in any building with two or more basements each exceeding 900m2
Fire service vehicle access level
Two or more basement storeys each exceeding 900m2
Extent of firefighting Extent of firefighting lift stair
NOTES:
1.Height excludes any top storey(s) consisting exclusively of plant rooms.
2.Firefighting shafts should serve all floors through which they pass.
See para 15.2
Firefighting shafts and protected stairways should be positioned such that every part of each storey more than 18m above the fire and rescue service vehicle access level complies with the maximum distances given in paragraph 15.7. Distances should be measured from the fire main outlet on a route suitable for laying a hose.
NOTE: If the internal layout is not known, the distance should be measured at two-thirds of the direct distance.
ventilation opening
The door of any doorway or exit should be hung to open in the direction of escape whenever reasonably practicable. It should always be hung to open in the direction of escape if more than 60 people might be expected to use it during a fire.
Any door opening towards a corridor or a stair should be recessed to prevent its swing encroaching on the effective width.
Where revolving doors, automatic doors and turnstiles are placed across escape routes they should comply with one of the following.
a. They are automatic doors of the required width and comply with one of the following conditions.
i. Their failsafe system provides outward opening from any open position.
ii. They have a monitored failsafe system to open the doors if the mains electricity supply fails.
iii. They failsafe to the open position if the power fails.
b. Non-automatic swing doors of the required width are provided immediately adjacent to the revolving or automatic door or turnstile.
A protected shaft conveying piped flammable gas should be ventilated direct to the outside air, by ventilation openings at high and low level in the shaft.
Any extension of the storey floor into the protected shaft should not compromise the free movement of air throughout the entire length of the shaft.
Guidance on shafts conveying piped flammable gas, including the size of ventilation openings, is given in BS 8313.
volume
In every case measure the volume contained by all of the following.
a. Under surface of roof.
b. Upper surface of lowest floor.
c. Inner surface of enclosing walls.
When there is not an outer enclosingwall, measure to the outermost edge of the floor slab.
The measured volume should include internal walls and partitions.
a. Cubic capacity of a building Internal wall or partition
b. Cubic capacity of compartments or separated part of a building
Diagram D2 Cubic capacity
This approved document has been published in two volumes. Volume 1 deals solely with dwellings, including blocks of flats, while Volume 2 deals with all other types of building covered by the Building Regulations
Volume 1 purpose groups
Purpose for which the building or compartment of a building is intended to be used
Residential(dwellings)
1(a)(1)Flat.
1(b)(2)Dwellinghouse that contains a habitable storey with a floor level a minimum of 4.5m above ground level up to a maximum of 18m.
(3)1(c)(2)(4)Dwellinghouse that does not contain a habitable storey with a floor level a minimum of 4.5m above ground level.
In sheltered housing, the guidance in Approved Document B Volume 2 should be consulted for the design of communal facilities, such as a common lounge.
Method 1 should not be used for extract ductwork passing through the enclosures of protected escape routes (Diagrams 9.3 and 9.4), as large volumes of smoke can pass thermal devices without triggering them.
For non-residential sprinkler systems designed and installed to BS EN 12845, water supplies should
consist of either of the following.
a. Two single water supplies complying with clause 9.6.1, independent of each other.
b. Two stored water supplies meeting all of the following conditions.
i. Gravity or suction tanks should satisfy all the requirements of clause 9.6.2(b), other than
capacity.
ii. Any pump arrangements should comply with clause 10.2.
iii. In addition to meeting the requirements for inflow, either of the following should apply.
• The capacity of each tank should be at least half the specified minimum water volume
of a single full capacity tank, appropriate to the hazard.
• One tank should be at least equivalent to half the specified water volume of a single
full capacity tank, and the other shall not be less than the minimum volume of a
reduced capacity tank (see clause 9.3.4) appropriate to the hazard.
The total capacity of the water supply in (iii), including any inflow for a reduced capacity
tank, should be at least that of a single full holding capacity tank that complies with
vomitory exits
Final exits should not present a barrier for disabled people. Where the route to a final exit does not include stairs, a level threshold and, where necessary, a ramp should be provided.
Final exit locations should be clearly visible and recognisable.
wall
External fire spread
B4.(1)The external walls of the building shall adequately resist the spread of fire over the walls and from one building to another, having regard to the height, use and position of the building.
(2)The roof of the building shall adequately resist the spread of fire over the roof and from one building to another, having regard to the use and position of the building.
Regulation 7 – Materials and workmanship
(1)Building work shall be carried out—
(a)with adequate and proper materials which—
(i)are appropriate for the circumstances in which they are used,
(ii)are adequately mixed or prepared, and
(iii)are applied, used or fixed so as adequately to perform the functions for which they are designed; and
(b)in a workmanlike manner.
(2)Subject to paragraph (3), building work shall be carried out so that materials which become part of an external wall, or specified attachment, of a relevant building are of European Classification A2-s1, d0 or A1, classified in accordance with BS EN 13501-1:2007+A1:2009 entitled “Fire classification of construction products and building elements. Classification using test data from reaction to fire tests” (ISBN 978 0 580 59861 6) published by the British Standards Institution on 30th March 2007 and amended in November 2009.
(3)Paragraph (2) does not apply to—
(a)cavity trays when used between two leaves of masonry;
(b)any part of a roof (other than any part of a roof which falls within paragraph (iv) of regulation 2(6))if that part is connected to an external wall;
(c)door frames and doors;
(d)electrical installations;
(e)insulation and water proofing materials used below ground level;
(f)intumescent and fire stopping materials where the inclusion of the materials is necessary to meet the requirements of Part B of Schedule 1;
(g)membranes;
(h)seals, gaskets, fixings, sealants and backer rods;
(i)thermal break materials where the inclusion of the materials is necessary to meet the thermal bridging requirements of Part L of Schedule 1; or
(j)window frames and glass.
(4)In this regulation—
(a)a “relevant building” means a building with a storey (not including roof-top plant areas or any storey consisting exclusively of plant rooms) at least 18 metres above ground level and which—
(i)contains one or more dwellings;
(ii)contains an institution; or
(iii)contains a room for residential purposes(excluding any room in a hostel, hotel or boarding house); and
(b)“above ground level” in relation to a storey means above ground level when measured from the lowest ground level adjoining the outside of a building to the top of the floor surface of the storey.
The external envelope of a building should not contribute to undue fire spread from one part of a
building to another part. This intention can be met by constructing external walls so that both of
the following are satisfied.
a. The risk of ignition by an external source to the outside surface of the building and spread of
fire over the outside surface is restricted.
b. The materials used to construct external walls, and attachments to them, and how they are
assembled do not contribute to the rate of fire spread up the outside of the building.
The extent to which this is necessary depends on the height and use of the building.
In every case measure the volume contained by all of the following.
a. Under surface of roof.
b. Upper surface of lowest floor.
c. Inner surface of enclosing walls.
When there is not an outer enclosingwall, measure to the outermost edge of the floor slab.
The measured volume should include internal walls and partitions.
a. Cubic capacity of a building Internal wall or partition
b. Cubic capacity of compartments or separated part of a building
Diagram D2 Cubic capacity
Free area measured at right angles to air flow
Free area for louvred vent = a1+a2+a3+a4+a5
Table 10.1 Reaction to fire performance of external surface of walls
‘Relevant buildings’ as defined in regulation 7(4) (see paragraph 10.10)
NOTES:
In addition to the requirements within this table, buildings with a top occupied storey above 18m should also meet the provisions of paragraph 10.6.
In all cases, the advice in paragraph 10.4 should be followed.
1. The restrictions for these buildings apply to all the materials used in the external wall and specified attachments (see paragraphs 10.9 to 10.12 for further guidance).
2. Profiled or flat steel sheet at least 0.5 mm thick with an organic coating of no more than 0.2mm thickness is also acceptable.
3. Timber cladding at least 9mm thick is also acceptable.
4. 10m is measured from the top surface of the roof.
The external wall of a building should not provide a medium for fire spread if that is likely to be a risk to health and safety. Combustible materials and cavities in external walls and attachments to them can present such a risk, particularly in tall buildings. The guidance in this section is designed to reduce the risk of fire spread as well as the risk of ignition from flames coming from adjacent buildings.
Regulation 7(1A) prohibits the use of relevant metal composite materials in the external walls of all buildings of any height.
External walls and specified attachments are defined in regulation 2(6) and these definitions
include any parts of the external wall as well as balconies, solar panels and solar shading.
Regulation 7(3) provides an exemption for certain components found in external walls and specified attachments.
Regulations 5(k) and 6(3) provide that, where the use of a building is changed such that the building becomes a building described in regulation 7(4), the construction of the external walls, and specified attachments, must be investigated and, where necessary, work must be carried out to ensure they only contain materials achieving class A2-s1, d0 or class A1, other than those exempted by regulation 7(3).
This section provides guidance on resisting fire spread over external walls; however, it does not deal with fire resistance of external walls. An external wall may need fire resistance to meet the provisions of Section 3 (Means of escape – flats), Section 6 (Loadbearing elements of structure – flats), Section 11 (Resisting fire spread from one building to another) or Section 15 (Access to buildings for firefighting personnel – flats).
The external walls of buildings other than those described in regulation 7(4) of the Building Regulations should achieve either of the following.
a. Follow the provisions given in paragraphs 10.5 to 10.9, which provide guidance on all of the following.
i. External surfaces.
ii. Materials and products.
iii. Cavities and cavity barriers..
b. Meet the performance criteria given in BRE report BR 135 for external walls using full-scale test data from BS 8414-1 or BS 8414-2.
In relation to buildings of any height or use, consideration should be given to the choice of materials (including their extent and arrangement) used for the external wall, or attachments to the wall (e.g. balconies, etc.), to reduce the risk of fire spread over the wall.
The external surfaces (i.e. outermost external material) of external walls should comply with the provisions in Table 10.1. The provisions in Table 10.1 apply to each wall individually in relation to its proximity to the relevant boundary.
Wall sufficiently distant from relevant boundary to be a 100% unprotected area
Wall on or very close to the relevant boundary: very limited amounts of unprotected area
Wall not on, or not very close to, but not sufficiently far from relevant boundary that it can be a wholly unprotected area
Amount of unprotected area dependent on distance from relevant boundary
See para 11.4
Exclude external walls of stairways in a protected shaft when assessing unprotected areas (see Diagram 11.5).
In an otherwise protected wall, small unprotected areas may be ignored where they meet the conditions in Diagram 11.5.
Area of fire resisting wall with materials more than 1mm thick and with a reaction to fire performance worse than class B-s3, d2 = a x b
Area of wall counted as unprotected area = 0.5a x b
Area of fire resisting wall with materials having a reaction to fire performance better than class B-s3, d2
See para 11.7
The unprotected area of the external wall of a stairway forming a protected shaft may be disregarded for separation distance purposes
Roofs pitched at an angle of less than 70 degrees may be disregarded for separation distance purposes
Represents an unprotected area of not more than 1m2 which may consist of two or more smaller areas within an area of 1000mm X 1000mm
Represents an area of not more than 0.1m2
See para 11.11
Parts of an external wall with less fire resistance than the appropriate amount given in Appendix B, Table B4, are called unprotected areas.
Where a fire resisting external wall has an external surface material that is worse than class B-s3, d2 and is more than 1mm thick, that part of the wall should be classified as an unprotected area equating to half its area (Diagram 11.4).
Unprotected areas should not exceed the result given by one of the methods in paragraph 11.16, and the rest of the wall (if any) should be fire resisting but only from the inside of the building.
In a building with a storey 18m or more above ground level any insulation product, filler material (not including gaskets, sealants and similar) etc. used in the external wall construction should be of limited combustibility (see Appendix A). This restriction does not apply to masonry cavity wall construction
All of the following precautions should be taken to avoid the spread of smoke and fire to the protected stairway.
a. Transfer grilles should not be fitted in any wall, door, floor or ceiling of the stair enclosure.
b. Any duct passing through the stair enclosure should be rigid steel. Joints between the ductwork and stair enclosure should be fire-stopped.
c. Ventilation ducts supplying or extracting air directly to or from a protected stairway should not serve other areas as well.
d. Any system of mechanical ventilation which recirculates air and which serves both the stair and other areas should be designed to shut down on the detection of smoke within the system.
e. For ducted warm air heating systems, a room thermostat should be sited in the living room. It should be mounted at a height between 1370mm and 1830mm above the floor. The maximum setting should be 27°C.
NOTE: Ventilation ducts passing through compartment walls should comply with the guidance in Section 9.
Configurations of stairs and external wall
Fire resisting construction
Fire resisting construction of adjacent building enclosure of protected stairway
Non-fire resisting construction
See para 3.63
For systems circulating air only within an individual flat, take all of the following precautions.
a. Transfer grilles should not be fitted in any wall, door, floor or ceiling of the enclosure.
b. Any duct passing through the enclosure should be rigid steel. Joints between the ductwork and enclosure should be fire-stopped.
c. Ventilation ducts serving the enclosure should not serve any other areas.
d. Any system of mechanical ventilation which recirculates air and which serves both the stair and other areas should be designed to shut down on the detection of smoke within the system.
e. For ducted warm air heating systems, a room thermostat should be sited in the living room. It should be mounted at a height between 1370mm and 1830mm above the floor. The maximum setting should be 27°C.
NOTE: Ventilation ducts passing through compartment walls should comply with the guidance in Section 9.
A ramp forming part of an escape route should meet the provisions in Approved Document M. Any sloping floor or tier should have a pitch of not more than 35 degrees to the horizontal.
With some configurations of external wall, a fire in one part of a building could subject the external wall of a protected stairway to heat (for example, where the two are adjacent at an internal angle in the façade, as shown in Diagram 3.10).
If a protected stairway projects beyond, is recessed from or is in an internal angle of the adjoining external wall of the building, then the minimum distance between an unprotected area of the building enclosure and an unprotected area of the stair enclosure should be 1800mm.
The surface linings of walls and ceilings should meet the classifications in Table 4.1.
For the purposes of this requirement, a wall includes both of the following.
a. The internal surface of internal and external glazing (except glazing in doors).
b. Any part of a ceiling which slopes at an angle greater than 70 degrees to the horizontal.
Parts of walls in rooms may be of lower performance than stated in Table 4.1, but no worse than class D-s3, d2. In any one room, the total area of lower performance wall lining should be less than an area equivalent to half of the room’s floor area, up to a maximum of 20m2 of wall lining.
Fire doors between the garage and dwellinghouse to have a minimum fire resistance of E30 Sa and be fitted with a self-closing device
Wall and any floor between the garage and dwellinghouse to have a minimum fire resistance of REI 30 from the garage side
The door opening threshold should be a minimum of 100mm above garage floor or
Floor to fall away from door to the outside
See paras 5.6 and 5.7
Elements of structure such as structural frames, beams, columns, loadbearing walls (internal and external), floor structures and gallery structures should have, as a minimum, the fire resistance given in Appendix B, Table B3.
Materials achieving class B-s3, d2 or worse used as a substrate to the roof covering and any timber tiling battens, fully bedded in mortar or other suitable material for the width of the wall (Diagram 5.2b), may extend over the compartment wall in buildings that are a maximum of 15m high.
Double-skinned insulated roof sheeting should incorporate a band of material rated class A2-s3, d2 or better, a minimum of 300mm in width, centred over the wall.
As an alternative to the provisions of paragraphs 5.12 to 5.14, the compartment wall may extend through the roof for a minimum of either of the following (see Diagram 5.2c).
a. Where the height difference between the two roofs is less than 375mm, 375mm above the top surface of the adjoining roof covering.
b. 200mm above the top surface of the adjoining roof covering where either of the following applies.
i. The height difference between the two roofs is 375mm or more.
ii. The roof coverings either side of the wall are of a material classified as BROOF(t4).
It is not appropriate to complete a line of compartment walls by fitting cavity barriers above them. The compartment wall should be extended to the underside of the floor or roof above.
a. ANY BUILDING OR COMPARTMENT
Roof covering over this distance to be designated BROOF(t4) rated on deck of material of class A2-s3, d2 or better. Roof covering and deck could be composite structure, e.g. profiled steel cladding.
Fire-stopping to be carried up to underside of roof covering, boarding or slab.
Roof covering to be designated BROOF(t4) rated for at least 1500mm either side of wall.
b. RESIDENTIAL (DWELLINGS) AND RESIDENTIAL (OTHER) A MAXIMUM OF 15M HIGH
Boarding (used as a substrate) or timber tiling battens may be carried over the wall provided that they are fully bedded in mortar (or other no less suitable material) where over the wall.
Thermoplastic insulation materials should not be carried over the wall.
Double-skinned insulated roof sheeting with a thermoplastic core should incorporate a band of material of class A2-s3, d2 at least 300mm wide centred over the wall.
Sarking felt may also be carried over the wall.
If roof support members pass through the wall, fire protection to these members for a distance of 1500mm on either side of the wall may be needed to delay distortion at the junction (see paragraph 5.9).
Double-skinned insulated roof sheeting should incorporate a band of material rated class A2-s3, d2 or better, a minimum of 300mm in width, centred over the wall.
If roof support members pass through the wall, fire protection to these members for a distance of 1500mm on either side of the wall may be needed to delay distortion at the junction (see paragraph 5.9).
Fire-stopping to be carried up to underside of roof covering, e.g. roof tiles.
Section X–X
Roof covering to be designated BROOF(t4) rated for at least this distance.
Roofing battens and sarking felt may be carried over the wall.
Fire-stopping to be carried up to underside of roof covering above and below sarking felt.
NOTES:
1. Fire-stopping should be carried over the full thickness of the wall.
2. Fire-stopping should be extended into any eaves.
3. The compartment wall does not necessarily need to be constructed of masonry.
c. ANY BUILDING OR COMPARTMENT
The wall should be extended up through the roof for a height of at least 375mm above the top surface of the adjoining roof covering.
Where there is a height difference of at least 375mm between two roofs or where the roof coverings on either side of the wall are BROOF(t4) rated, the height of the upstand/parapet wall above the highest roof may be reduced to 200mm.
See paras 5.12 to 5.15
Timber beams, joists, purlins and rafters may be built into or carried through a masonry or concrete compartment wall if the openings for them are both of the following.
a. As small as practicable.
b. Fire-stopped.
If trussed rafters bridge the wall, failure of the truss due to a fire in one compartment should not cause failure of the truss in another compartment.
If a loadbearing wall is any of the following, guidance in other sections may also apply.
a. A compartment wall (including a wall common to two buildings): Section 7.
b. Enclosing a place of special fire hazard: Section 7.
c. Protecting a means of escape: Sections 2 and 3.
d. An external wall: Sections 10 and 11.
e. Enclosing a firefighting shaft: Section 15.
All of the following should be provided as compartment walls and compartment floors and should have, as a minimum, the fire resistance given in Appendix B, Table B3.
a. Any floor (unless it is within a flat, i.e. between one storey and another within one individual dwelling).
b. Any wall separating a flat from another part of the building.
c. Any wall enclosing a refuse storage chamber.
d. Any wall common to two or more buildings.
Compartment walls not described in paragraphs 7.8 and 7.9 should run the full height of the storey in which they are situated.
Compartment walls in a top storey beneath a roof should be continued through the roof space.
At the junction of a compartment floor and an external wall with no fire resistance, the external wall should be restrained at floor level. The restraint should reduce movement of the wall away from the floor if exposed to fire.
Compartment walls should be able to accommodate deflection of the floor, when exposed to fire, by either of the following means.
a. Between the wall and floor, provide a head detail that is capable of maintaining its integrity while deforming.
b. Design the wall so it maintains its integrity by resisting the additional vertical load from the floor above.
Where compartment walls are located within the middle half of a floor between vertical supports, the deflection may be assumed to be 40mm unless a smaller value can be justified by assessment. Outside this area, the limit can be reduced linearly to zero at the supports.
For steel beams that do not have the required fire resistance, reference should be made to SCI Publication P288.
Double-skinned insulated roof sheeting with a thermoplastic core should incorporate a band of material rated class A2-s3, d2 or better, a minimum of 300mm in width, centred over the wall.
As an alternative to the provisions of paragraph 7.16 or 7.17, the compartment wall may extend through the roof for a minimum of either of the following (see Diagram 5.2c).
a. Where the height difference between the two roofs is less than 375mm, 375mm above the top surface of the adjoining roof covering.
b. 200mm above the top surface of the adjoining roof covering where either of the following applies.
i. The height difference between the two roofs is 375mm or more.
ii. The roof coverings either side of the wall are of a material classified as BROOF(t4).
Openings in a compartment wall common to two or more buildings should be limited to those for either of the following.
a. A fire doorset providing a means of escape, which has the same fire resistance as the wall and is fitted in accordance with the provisions in Appendix C.
b. The passage of a pipe that complies with the provisions in Section 9.
The external wall of a protected shaft does not normally need to have fire resistance. Situations where there are provisions are given in paragraph 3.63 (external walls of protected stairways, which may also be protected shafts) and paragraphs 15.8 to 15.11 (firefighting shafts).
Openings in other parts of the enclosure to a protected shaft should be limited to the following.
a. If a wall common to two or more buildings forms part of the enclosure, only the following openings should be made in that wall.
i. A fire doorset providing a means of escape, which has the same fire resistance as the wall and is fitted in accordance with the provisions in Appendix C.
ii. The passage of a pipe that meets the provisions in Section 9.
b. Other parts of the enclosure (other than an external wall) should only have openings for any of the following.
i. Fire doorsets of the appropriate fire resistance, fitted in accordance with the provisions in Appendix C.
ii. The passage of pipes which meet the provisions in Section 9.
iii. Inlets to, outlets from and openings for a ventilation duct (if the shaft contains or serves as a ventilating duct), meeting the provisions in Section 9.
iv. The passage of lift cables into a lift machine room (if the shaft contains a lift). If the machine room is at the bottom of the shaft, the openings should be as small as practicable.
Timber beams, joists, purlins and rafters may be built into or carried through a masonry or concrete compartment wall if the openings for them are both of the following.
a. As small as practicable.
b. Fire-stopped.
If trussed rafters bridge the wall, failure of the truss due to a fire in one compartment should not cause failure of the truss in another compartment.
It is not appropriate to complete a line of compartment walls by fitting cavity barriers above them. The compartment walls should extend to the underside of the floor or roof above.
The wall of a flue, duct containing flues or appliance ventilation duct(s) should have a fire resistance (REI) that is at least half of any compartment wall or compartment floor it passes through or is built into (Diagram 9.5).
Provide a proprietary, tested sealing system that will maintain the fire resistance of the wall, floor or cavity barrier.
wind load
The following are excluded from the definition of ‘element of structure’.
a. A structure that supports only a roof, unless either of the following applies.
i. The roof performs the function of a floor, such as a roof terrace, or as a means of escape.
ii. The structure is essential for the stability of an external wall that needs to be fire resisting (e.g. to achieve compartmentation or for the purposes of preventing fire spread between buildings).
b. The lowest floor of the building.
c. External walls, such as curtain walls or other forms of cladding, which transmit only self weight and wind loads and do not transmit floor load.
NOTE: In some cases, structural members within a roof may be essential for the structural stability system of the building. In these cases, the structural members in the roof do not just support a roof and must demonstrate the relevant fire resistance for the building as required by paragraph 5.2 above.
The following are excluded from the definition of ‘element of structure’.
a. A structure that supports only a roof, unless either of the following applies.
i. The roof performs the function of a floor, such as for parking vehicles, or as a means of escape.
ii. The structure is essential for the stability of an external wall that needs to be fire resisting (e.g. to achieve compartmentation or for the purposes of preventing fire spread between buildings).
b. The lowest floor of the building.
c. A platform floor.
d. External walls, such as curtain walls or other forms of cladding, which transmit only self weight and wind loads and do not transmit floor load.
NOTE: In some cases, structural members within a roof may be essential for the structural stability system of the building. In these cases, the structural members in the roof do not just support a roof and must demonstrate the relevant fire resistance for the building as required by the note to paragraph 6.1 above.
window
Each basement space should have one or more smoke outlets.
Where this is not practicable (for example, the plan area is deep and the amount of external wall is restricted by adjoining buildings), the perimeter basement spaces may be vented, with other spaces vented indirectly by opening connecting doors. This does not apply for places of special fire hazard (see paragraph 16.7).
If a basement is compartmented, each compartment should have one or more smoke outlets, rather than indirect venting.
A basement storey or compartment containing rooms with doors or windows does not need smoke outlets.
Windows or external doors providing emergency escape should comply with all of the following.
a. Windows should have an unobstructed openable area that complies with all of the following.
i. A minimum area of 0.33m2.
ii. A minimum height of 450mm and a minimum width of 450mm (the route through the window may be at an angle rather than straight through).
iii. The bottom of the openable area is a maximum of 1100mm above the floor.
b. People escaping should be able to reach a place free from danger from fire. Courtyards or inaccessible back gardens should comply with Diagram 2.5.
c. Locks (with or without removable keys) and opening stays (with child-resistant release catches) may be fitted to escape windows.
d. Windows should be capable of remaining open without being held.
Where an existing window would be an escape window in a new dwellinghouse, and is big enough to be used for escape purposes, then the replacement should comply with one of the following.
a. The replacement window should be sized to provide at least the same potential for escape.
b. If the existing window was larger than required for escape purposes, the opening can be reduced to the minimum described in paragraph 2.10.
If windows are replaced, it may be necessary to provide cavity barriers around the opening in accordance with Section 5.
An alternative approach to that described in paragraph 2.21 would be to comply with all of the following.
a. Provide sprinkler protection to the open-plan areas.
b. Provide a fire resisting partition (minimum REI 30) and door (minimum E 20) to separate the ground storey from the upper storeys. The door should allow occupants of the loft room access to a first storey escape window.
c. Separate cooking facilities from the open-plan area with fire resisting construction (minimum REI 30).
Two rooms may be served by a single window. A door between the rooms should provide access to the window without passing through the stair enclosure. Both rooms should have their own access to the internal stair.
No fire resistance required for door
1100mm zone above top landing
1100mm zone above top landing
6m maximum height of stair
Fire resisting window (minimum RE30)
1800mm zone of fire resisting construction at side of stair
Fire doorset (minimum E30)
Ground level or a roof or podium served by an independent stairway
6m maximum height of stair without weather protection
9m zone of fire resisting construction below stair
Ground level or a roof or podium served by an independent stairway
See para 3.68
All habitable rooms (excluding kitchens) should have either of the following.
a. An emergency escape window or external door, as described in paragraph 3.6.
b. In multi-storey flats, direct access to a protected internal stairway (minimum REI 30) leading to an exit from the flat.
Two rooms may be served by a single escape window. A door between rooms should provide access to the escape window without passing through the stair enclosure. Both rooms should have their own access to the internal stair.
Access openings to refuse storage chambers should not be sited in the following areas.
a. Next to escape routes or final exits.
b. Near the windows of flats.
Windows or external doors providing emergency escape should comply with all of the following.
a. Windows should have an unobstructed openable area that complies with all of the following.
i. A minimum area of 0.33m2.
ii. A minimum height of 450mm and a minimum width of 450mm (the route through the window may be at an angle rather than straight through).
iii. The bottom of the openable area is a maximum of 1100mm above the floor.
b. People escaping should be able to reach a place free from danger from fire.
c. Locks (with or without removable keys) and opening stays (with child-resistant release catches) may be fitted to escape windows.
d. Windows should be capable of remaining open without being held.
Thermoplastic material classified as a TP(a) rigid product may be used to glaze external windows to rooms, but not external windows to circulation spaces. Approved Document K includes guidance on the safety of glazing.
For the purposes of this requirement, a wall does not include any of the following.
a. Doors and door frames.
b. Window frames and frames in which glazing is fitted.
c. Architraves, cover moulds, picture rails, skirtings and similar narrow members.
d. Fireplace surrounds, mantle shelves and fitted furniture.
For the purposes of this requirement, a ceiling does not include any of the following.
a. Trap doors and their frames.
b. The frames of windows or rooflights and frames in which glazing is fitted.
c. Architraves, cover moulds, picture rails, exposed beams and similar narrow members.
Thermoplastic materials used for window glazing, rooflights and lighting diffusers within suspended ceilings do not need to meet the criteria within paragraph B19 onwards, if the guidance to requirements B2 and B4 is followed.