Insulating ceiling of garage
I’m looking to air seal and insulate the ceiling of my garage. Our kitchen is above it and we have quite a few pipe penetrations as well as three beams in the garage. The joists are 2×10 and 12″ OC. The ceiling already has type x drywall on it and the rim joists have 3.5″ of closed cell on them.
I’m thinking of strategically cutting the drywall and installing 3.5″ of closed cell foam. Does it make sense to then install mineral wool if it can be compressed by the drywall? Areas around the beams, plumbing, etc could have some mineral wool but it would be difficult to compress due to the soffits. I’m trying to be judicious with the closed cell as the ceiling is 700 square feet. Any other recommendations? We’re in climate zone 4a.
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