Vapor Permeability for Metal Roof Assembly
Hey all! I just bought a house in Buffalo, NY climate zone 5a. I have several projects on my radar but I am zeroing in on the first being a pitched roof (6/12) retrofit. I would like to do a full tear off down to sheathing, roll a peel and stick membrane over it (provided it is in good shape) to simplify my roof air sealing. Then go over it with rigid or semi rigid insulation, attach spacers and bug screen, then metal roof.
My question is, in this assembly, should I try to keep the whole assembly vapor permeable, including the membrane?
I haven’t lived in the house long so I don’t have a good idea of what my vapor situation looks like now. Any advice?
Thanks so much,
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