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Can you use rigid insulation only? Exterior wall in zone 1

Jenjen0223 | Posted in Energy Efficiency and Durability on

We are enclosing a screened porch, reinforcing exterior walls on a 1969 trailer and then we plan on putting up rigid insulation over plywood sheathing and existing aluminum

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  1. GBA Editor
    Martin Holladay | | #1

    Yes, you can use a continuous layer of exterior rigid foam on the exterior side of your wall as your only insulation layer. Your plan will work. I advise you to install at least 2 inches of rigid foam, and to pay attention to airtightness when installing the foam.

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