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Insulating a Steel Garage Door

sewdivaish | Posted in Green Products and Materials on

I live in Ontario, Canada.  What is the best product to use to insulate my steel garage door.  My garage is insulated.

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  1. Expert Member
    Dana Dorsett | | #1

    It depends on the door's design. Can you post a picture?

  2. charlie_sullivan | | #2

    Buying foam insulation boards, cutting them, and gluing them to the door is cheaper and gives you more options than buying a garage door insulation kit. Leaving foam exposed is considered a fire hazard, and is often against code, but it's not clear that it's a major hazard or an actual code issue on a garage door. "Themax" polyiso insulation carries the best fire rating of any foam board insulation, so that could be a good choice. You could also use mineral wool boards, but then you'll most likely get condensation in the inside surface of the steel. A thin mineral wool board over a thick foam board would be more fire safe than foam alone and might avoid the condensation problem, if the foam is thicker than the mineral wool. But I don't know that you can get thin mineral wool boards, and I also don't know how you'd attach them.

    So probably "thermax" polyiso is the way to go.

  3. JC72 | | #3

    The best garage door is one which isn't leaky around the edges.

  4. GBA Editor
    Kiley Jacques | | #4

    Hi Jasmine,

    Here are a few Q&A threads with links to resources that might help inform your course of action: Ideal garage door insulation and Garage door insulation.

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