Confused about vapor barriers in attached garage
I live in MN and am insulating my garage ceiling in an attached garage. I’m so confused about vapor barriers. I’ve read the articles here and on other sites, and it seems like I can’t get a “final” decision.
On the one hand, I’ve read about how air leakage is the main culprit of transporting moisture, so I plan to air seal as best as I can with spray foam and caulk. Thus, I shouldn’t worry too much about moisture passing through drywall because it only does a little.
On the other hand, I will be conditioning this space in the winter so that I can work in my shop. Also, I’ll be driving snow-covered vehicles into the shop. So there’s a lot of snow melting and the temperature is about 45 degrees when heated. I feel like that’s a lot of moisture that I don’t want passing through to the cold sheathing.
What’s a guy to do?
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