Air sealing flat roof assembly
Remodeling a flat roof in climate zone 3. 1/2″ plywood sheathing is currently in place over previous 3/4″ sheathing. The plan is to add 2″ of polyiso and another 1/2″ plywood then either modified bitumen vs TPO
Question set 1: In terms of air sealing on top of the sheathing, I’ve seen both tapes and peel and stick membranes recommended. If I go with peel and stick what brands are good but cost effective? Do you recommend that I find something permeable? Is taping the seams alone ok? What are the tradeoffs?
Question 2 : Ay reason to use plywood on the top of this sandwich vs a coverboard? The roof will have moderate foot traffic and will house solar panels on skids.
Thanks in advance. Your site is amazing!
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