Hi, I'm building an external wall from 4x2, I've been advised by celotex of the correct insulation that is needed to comform to regs which is 100mm celotex between joists and 12m plasterboard with 1" celotex ( havent got the paperwork infront of me of correct thickness but im sure it was 1") attached to it to fit on the inside.
On the outside I am going to put 12mm ply and then wanted to put upvc hollow soffit on top.
The question I'm asking is should I put building paper on top of the ply then battens and then upvc?
On the outside I am going to put 12mm ply and then wanted to put upvc hollow soffit on top.
The question I'm asking is should I put building paper on top of the ply then battens and then upvc?