CAPTAIN GREALISH
Well-known member
- Jan 6, 2010
- 2,622
Seen that as well. Apparently you should not consider it if you live in an area where you are at risk of 'wind-driven rain' which probably means most people who live on or near the south and west coasts of the UK. The cavity is there to (1) keep a layer of air which will stop your house getting cold and (2) separate the innner and outer skins so that you don't get damp walls because of rain. Cavity wall insulation bridges the gap.
you must be in the building trade?