Insulate the common wall of an attached garage and the house
BTgarage
| Posted in General Questions on
Hello, Don’t know if this is something I can get help with, I am looking to insulate a common wall, this wall is share between the living room and the attached garage which is unconditioned, so cold in the winter and hot in the summer.Â
I like to open the wall from the garage side and insulate this wall, however I am not sure If I would need a vapor barrier, and if I do where and how to do it correctly, the home is in US Zone 4 (not marine)
any suggestion would be great, thank you so much
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Replies
BTgarage,
You don't need a vapour barrier - the painted drywall on the living room side will be fine acting as a vapour-retarder. What will help the wall perform better is a good air-barrier. Probably the easiest for that is to use the existing drywall while the wall is open. Seal the backside of all electrical boxes and other penetrations, and go around each stud cavity with a bead of caulking. Making sure the garage side drywall is also fairly tight will help keep fumes out of the house. That drywall should be 5/8".
Thank you so much for the help, does it matter what kind of Insulation I get?
BTgarage,
Not particularly. You can increase the R value slightly by using either high density fiberglass or rockwool, but the difference in energy loss in climate zone 4 will be in the weeds.