With increasing pressure to provide ever thicker levels of insulation there is concern that thermally upgrading conventional cavity walls, consisting of two leaves of masonry, may prove impracticable. Part 1 of this Good Building Guide highlights techniques and materials for insulating cavity walls. Part 2 provides guidance on how to reduce the associated technical risks. It includes a map of national exposure zones for wind-driven rain. The guidance is for cavity walls having two masonry leaves; it is not suitable for timber-framed construction.

 NB it relates more to new-build housing than to retrofitting insulation, but it does include some advice relevant to filling cavities in existing homes.

This pdf is Part 2 only. (8 pages)