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Wall assembly

Ccloud | Posted in General Questions on

I am building a new home in zone 6. I have a question regarding insulation in the window wells. I have 4 inches of xps externally. Of course I do not have insulation inside the window well area. That leaves the header area and a small amount around the window uninsulated. Should I use an internal insulation in the stud bays around this area? One window well is in a bathroom. Should a smart membrane be installed in this area?

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  1. GBA Editor
    Martin Holladay | | #1

    The best approach would be to install insulation on the exterior side of the foundation, even in the window well area. In fact, this area should have been insulated before the foundation was backfilled, and before the window well was installed.

  2. Ccloud | | #2

    Martin, I insulated up to the outside of the wells. That leaves about 3 inches on the sides (inside) and the area above the window. I left this area clear for flashing of the window. It has not been back filled yet and the windows are not installed.

  3. GBA Editor
    Martin Holladay | | #3

    I recommend that you do your best to install exterior insulation on the uninsulated areas near the window.

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