What's the difference between EPS and GPS insulation?
While searching to purchase EPS boards, which are very difficult to find here in QC, I've bumped into a 4' x 8' x 1" thick board, called GPS. Do you have a webpage about GPS insulation? I want to insulate my existing basement concrete floor, on top of it. I have very limited head room, no more than 5 ft where there is no pipes on the ceiling.