Interior Wall Moisture with Metal Siding
Hello, long time reader and have gathered a ton of information from the site, and ready many articles and forum posts.
My question is in regards to a new construction 32×40 garage with a 2 bedroom apartment overhead located in climate zone 5a/5b in Maine. We built it this summer, and the down stairs is heated by radiant in the slab kept at 60 degrees, upstairs is dense pack cellulose in the 2×12 rafters and 2×6 stud walls heated with 1 15k btu heat pump. The garage area is a 12′ 2×6 wall insulated with rockwool that I just completed last month. After our recent cold weather, single digits in the day, I pulled back some rockwool and found lots of moisture and frost. The exterior is zip sheathing taped and nail holes filled, with ribbed metal siding. We haven’t been parking snow covered vehicles in there, and there’s no moisture on any windows or the garage doors.
I understand my moisture problems are more than likely just from there being no interior vapor barrier or sheetrock on the inside. Going forward will the assembly dry back through the insulation as the temperatures moderate, or will all the insulation need to be removed? Does the ribbed metal siding prohibit the walls ability to dry to the exterior? For a garage is installing intello membrane a good idea, and I’m assuming I’ll have to wait until the wall cavity is dry before I can install it? Thanks in advance!
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