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Insulating exterior electrical box from inside

JakeNY | Posted in General Questions on

In my laundry room wall is the electrical box for one of my exterior lights. That wall cavity is open and I would like to insulate it from the inside. Getting it from the outside is difficult for me because of obstacles.

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  1. Steve Knapp CZ 3A Georgia | | #1


    You may not gain much by insulating a single electrical box, but you can certain air seal it using caulk or low-expansion foam.

  2. GBA Editor
    Martin Holladay | | #2

    If your stud bay is open, the usual rules apply: Caulk any obvious air leaks (including leaks through the back of the electrical box), and then install insulation in the stud bay.

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