So my friend has a 20 x 20 roof deck that is laid on top of a concrete roof. The rood is pitched an there is drainage at the corner. The current deck is about 8 years old and is curling, splitting and coming up like crazy. The deck was there when he purchased the place. There are a couple things that come to my attention ...
The decking is laid on top of 2x4s that are laid on top of foam-core, but the are laid flat rather than like joists.
The decking seams thinker than usual 1 1/2", I'm used to 5/4
The drainage looks suspect ... it's possible that it all drains in
one direction and at the end makes it's way across the roof to the
drain but I cant tell
It's painted on top an not on the bottom
It looks like they used non epoxy coated screws ... I see allot of
rust on the screws
I'm looking for some recommendations on how to re-build this I Thought perhaps of mimicking the same design but cutting gaps in the foam to allow better drainage, and using some better beefier epoxy coated deck strews. Also, currently the boards are spanning 2', so if I use 5/4 deck boards, I think I might have to span less. Something else to factor in is the sun ... it gets pretty hot up there, no shade at all.
Any advise or experience would be appreciated, I would hate to re-buiid this thing only to have the same exact problem. Please see photos