Diagram 5.3 Cavity walls excluded from provisions for cavity barriers

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