Ceiling Vapor Barrier Condensation
I’m remodeling a house built in the 70s with a flat roof that has minimal ventilation in some of the eaves. While removing the ceiling drywall I decided to also take out the old fiberglass R19 and replace with mineral wool R30. I had to do this during a heat wave of 95° for several days. My wife came over to check on the progress and insisted we turn on the AC since it was also about 95° inside the home. When I went back to finish installing the vapor barrier there was condensation everywhere on the inside of the barrier that had already been installed and also on the exposed mineral wool that hadn’t yet been covered with plastic.
The roof assembly is EPDM/half inch fiberboard/roof deck/2×10 joists (now with 7.5” mineral wool) Certainteed Membrain and eventually new drywall.
I’m in Minnesota and the vapor barrier is required by code. I’m officially out of my depths here on what to do and wondering if I’m totally screwed. I have a drywall scheduled to be installed next week and am worried it will be trapping all that moisture in there.
The certainteed membrain is supposed to change its permeability and allow drying to the inside but I don’t know how long that would take.
Thanks for any guidance.
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