i would not build a wood deck over a rubber roof.

i would use a thick at least 60 mil membrane and use a fully adhered walking surface that is compatable to the roofing system you use. this way the whole system is covered under whatever warrenty they offer.

make sure you follow their guidelines for the surface you are installing it on and if a sloping roof is coming down to it run the membrane up the slope under your shingles at least two feet to avoid capillary action when the snow melts.

if you have a handrail i always try to attach it under the roofing membrane to the side of the roof structure so that it is completely outside the membrane and does not penetrate it.

this is a tough thing to build correctly, and if not done correctly it will cause trouble later.

good luck.

tom w

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.