Insulating wall of attached garage
Hi I just wanted to double check my thinking here with the pros. Got a 50s prefab cape in VT. An addition was built ooff back of house connecting existing garage to house. They now share a wall. On the house side it’s 2x4framing with batt insulation and a vapor barrier on conditioned side of house. On the garage side it’s now 3/4 sheathing (yup 3/4) and 2×6 framing. Looks like the garage sheathing between house may have house wrap on it.
I’m thinking of adding 5_1/2 rockwool between studs in garage. Garage sill plate is on open (non filled) CMU and the garage generally gets pretty humid when it rains. I’m a little concerned about trapping humidity in this wall system since its essentially a double stud wall with sheathing between the two, and vapor barriers on one of the walls. Could adding insulation on garage side prevent framing and sheathing from drying out.
Overall the house is pretty effecoent so I don’t necessarily need the insulation between garage and house, I’m just looking for sound dampening qualities.
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