Masonry cavity walls: Brick

Abstract

Brick cavity walls have the advantage of providing a cavity within the depth of a wall for drainage of rainwater before it is allowed to be absorbed too far into the wall construction. Whereas loadbearing brick walls use the overall wall thickness to stop the passage of rainwater from outside to inside, cavity walls use two skins of brickwork separated by a ventilated air gap. The inner skin is increasingly formed in concrete block, hollow terracotta block or timber studwork. Thermal insulation is usually set on the external face of the inner skin in order to keep the building structure insulated.