Locations Where CWI Should Only Be Installed with Caution

The cavity in between the inner and outer wall is there for a reason.

Since the 1920’s, properties in areas exposed to wind driven rain have been built with a cavity, to act as a dry barrier to prevent damp passing from the porous outer wall, directly in to the house.

This doesn’t mean that those exposed properties shouldn’t have CWI installed, but they certainly require very careful surveys, specialist materials and registered professionals, acting as installers.

On the map below, traditional CWI types, should not have been used in zones 3 and 4.