New roof over spray foamed attic
I’m putting a new roof on my 1850s Maine farmhouse. I had the ceilings in the attics sprayfoamed to the floor of the attic. The roof continues over kneewalls in the second story, and does not have spray foam there. I have a mildew smell coming from that area on one side of this house, and trapped condensation may be the cause (we’ll know better when we get to that area in the roof replacement).
I want to make sure the new roof does not have any condensation issues. The roofers mentioned that in a previous situation like mine that they had reroofed, condensation had formed between the roof shingles/sheathing and the foam, and the water had no place to escape because of the spray foam, causing mold and rot. I’d like to make sure the new roof has all the precautions possible.
Any advice for my situation?
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