I was under the impression that for a 100mm cavity wall (ground floor extension) which has solid concrete floors, that you needed to leave some 50mm free. Builder has put in 50mm thick kingspan rigid board insulation in there.
Just went to see a friend's place who is also doing a single storey extension however they have put 100mm kingspan and filled the cavity.
Could I have also done this? I thought there needed to be a gap in the cavity?
Just went to see a friend's place who is also doing a single storey extension however they have put 100mm kingspan and filled the cavity.
Could I have also done this? I thought there needed to be a gap in the cavity?