Hi,
I have a flat garage roof that has started to leak. It currently has chipboard beneath the felt, which has started to expand and rot. So I need to totally replace the roof, replacing chipboard with 18mm WBP ply, then 3 layers of felt (2 underlay 1 top) Now my question is, the 1st layer of underlay, should I nail it to the ply boards, stick it, or leave it free moving. I read this website
Who is right?
Any help greatly appreciated!
Cheers
Ben
"Thanks to God, I am Still an Atheist"