Insulating a Steel Garage Door
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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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Replies
It depends on the door's design. Can you post a picture?
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.
The best garage door is one which isn't leaky around the edges.
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.