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Garage under living space

user-1085018 | Posted in Energy Efficiency and Durability on

I am wondering about the proper technique for air sealing and insulating a house with a garage in basement level. I live in Vt.

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  1. GBA Editor
    Martin Holladay | | #1

    First of all, you need to do a very careful job of air sealing between the garage and your living space. The subfloor should be attached with construction adhesive, and all penetrations (wiring, plumbing, etc.) should be carefully air sealed. This work should be verified with a blower door.

    Second, I advise you to include an exhaust fan in the garage to depressurize the garage when the fan is in operation. The fan should turn on automatically whenever the garage door is opened, and should have a control that continues to operate the fan for several minutes after the garage door is closed.

  2. belmanliving | | #2

    Agreed Martin. Identify the walls of the garage that need sealing. insulate these walls the same way the exterior walls of the house are insulated. Identify any penetrations in the walls and use a fire-rated caulk, adhesive, or expanding foam to seal up these penetrations.

  3. KROregon | | #3

    You will need a dehumidifier, if not an ERV. My garage is insulated and becomes extremely humid during winter when the car comes in with snow on the tires and undercarriage.

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