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Community and Q&A

Superinsulated garage doors — again

jinmtvt | Posted in General Questions on

I know garage doors have been debated quite alot already,
but i haven’t found any mention of anybody trying to actually “add ” insulation to an existing door

I was looking at residential and commercial garage door manufacturers website a few moments ago, amazed on how “their special” polyurethane achieve R16 at only 1.75″
( they must be onto something we do not know!! )

And i notice the lack of new solutions for cold climate situation other than
the 2″ thick steel/poly/steel slabs they advertise as R18 , which is probably closer to R8-R10.

And then, i though about something i did in the past…
we modified an older steel type door by gluing aluminum composite panels ( ACP )
which are prepainted in kynar, to the exterior of the door..
ok it was 3mm thick and we only had to move the weather seals a bit..but it was very easily done,
since the door joints ” open up” on the exterior side.

So, why aren’t we already laminating insulation boards on the exterior of all our garage doors?
Anyone done it yet ??? i don’t believe it would be very hard to glue or fasten a rigid XPS or very dense EPS 2″ board at the exterior side …

The only thing required to be modified is the length of the legs holding the roller tracks to the wall
( and maybe the header spring distance to wall ?? )

What do you think ?
I have many projects to come in the following years , all of which will feature one or several garage doors … would be delighted to be able to use the “cheap” regular 1.75″ doors and only have to add insulation boards and a new finish of my choice on top of it ! 🙂

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  1. GBA Editor
    Martin Holladay | | #1

    There are several problems with your suggestion.

    1. You need a weatherproof facing for the rigid foam. The detail has to protect the edges as well as the exposed face.

    2. The main thermal performance problem with garage doors has nothing to do with R-value. The real problem is air leakage. If you want to improve the thermal performance of a garage door, focus on the air leaks. Reducing air leakage at the perimeter of the door is much harder than at the panel joints.

  2. jinmtvt | | #2

    Martin ...

    1. i don't tink it would be a problem... need to use some colored fascia neway..some weatherstripping
    could be used between the fascia material and the foam to make for a seal near the front plane when closed.

    2- air leakage ..of course is a traditional problem...have not yet got to working on a solution for this

    I was currently considering insulation because most of our garages here are fully insulated
    and usually kept pretty warm ( 15-19c settings )

    Then my next large project will feature something in the range of 600sqft of garage doors on a ~1500sq ft wall . This project will be super insulated, the doors need to work with it at this surface area ( north side ) . ( R40+ walls ... factory/shop building )

    What is currently the best air sealing solution for slab doors ?

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