Insulating garage workshop doors...

[dbhost]

I am not sure if I am wasting money and effort here, but this is what I am doing for garage door insulation.

Layer #1. Reflectix aluminum mylar bubble wrap type insulation bonded to the inside of the metal garage door with Liquid Nails Heavy Duty interior / exterior grade construction adhesive.

Layer #2. Owens Corning pink foam board insulation bonded over top of the reflectix using the Liquid Nails again.

The idea is twofold.

#1. To reduce heat gain, or loss by adding a reflective barrier.
#2. To reduce heat gain, or loss by impeding the movement of heated air (dead air space).

I have installed only the Reflectix on one door, as I am out of material, and need the $$ for other expenses, BUT, there is a noticable difference in heating through the door already.

The next steps I have in mind is taking split foam pipe wrap, most likely for 1.5, or 2" PVC, and liquid nails that to the inside edges so that the door gaps stay at least somewhat sealed, and fill the upper and lower inside edges of the panels with expanding foam.

Ah the things we do to keep from melting in the summer, and freezing in the winter...

[Uncle Cracker]

I feel your pain... I have 25 feet of doors on my garage, and they all face west. My garage can get to 125 degrees on a summer afternoon. There are too many cross-braces for the 150-mph wind rating to make adding insulation a doable job, but when I've got a spare couple thousand, I'm replacing them with double-wall insulated units.

[LarryG]

You'll also need a Layer #3: 1/8" hardboard, 26ga sheet metal, or similar. Rigid foam insulation should NEVER be left exposed as it is a HUGE fire hazard.

[thrytis]

Do you have an air gap on both sides of the Reflectix insulation? You're supposed to have one for maximum effectiveness.

Uncle Cracker, can you just tape the reflectix insulation over the entire door? As long as the cross braces are flush with the perimeter of the door panels, you should only have to secure it around the edges of the panels.

Insulating the door does make a huge difference. I can now work in my garage in the summer!

[dbhost]

Now that is why I bring this stuff up here. Thanks for the tip!

Now If I am going to enclose the cavity, why not just enclose it, and fill it with blow in insulation?

[thrytis]

Now If I am going to enclose the cavity, why not just enclose it, and fill it with blow in insulation?

Putting blow in insulation behind the reflectix will still probably reduce the radiant insulation ability some, though you will make up some of that with the conductive insulation of the blow in insulation. Since the door will move regularly, blow in insulation probably would settle pretty quickly, so you may want to look at fiberglass bats instead. I think they make some real thin (1" to 1.5").

[dbhost]

No air gap between the door, and the reflectix... Didn't say anything about that... I see on the packaging how it is supposed to be used on walls, and rafters and such though... Kind of makes sense...

Anyone have a pic of reflectix properly installed on a garage door? I have only seen it stuck directly to the panel...

[Uncle Cracker]

Uncle Cracker, can you just tape the reflectix insulation over the entire door? As long as the cross braces are flush with the perimeter of the door panels, you should only have to secure it around the edges of the panels.

If you saw the mass of lateral, longitudinal, and even diagonal (??) braces on these doors, you would see why this is not an easy solution. And with our humidity, even good quality duct tape does not hold for long in unconditioned space. Probably go the whole nine yards one of these days. Also want to to get rid of all the little windows in the process, as prying eyes can currently recon the shop.

[pelligrini]

Also want to to get rid of all the little windows in the process, as prying eyes can currently recon the shop.

My wife took a can of black spray paint to the windows in ours. Can't see in anymore.

Can't really notice if the windows are dirty anymore either.

[Uncle Cracker]

My wife took a can of black spray paint to the windows in ours. Can't see in anymore.

Yeah, that's the first thing I thought of, but the HOA stuck it's nose in. Seems there is a clause in the covenants about no painted windows. I was overjoyed...

[pelligrini]

Just put up some pink & yellow polka-dot curtains, maybe they'll make you paint the windows.

That's really strange about the windows, especially a black painted one. It looks like a really clean window with the lights off behind.

[poolhound]

Yeah, that's the first thing I thought of, but the HOA stuck it's nose in. Seems there is a clause in the covenants about no painted windows. I was overjoyed...

How about first painting some pretty curtains on them as seen from the outside and then black them out.

HOAs are one of my pet peeves. Some things make sense but what has an HOA got to do with how you deal with your garage windows!!!

[shoottx]

Yeah, that's the first thing I thought of, but the HOA stuck it's nose in. Seems there is a clause in the covenants about no painted windows. I was overjoyed...

Cover a board with insulated curtains. Use a material that will reflect the sun, and line them with some sort of insulation material. Use the inside of the board as a place to mount pictures of the outside.

[dbhost]

Thankfully, I have no windows of any sort in my garage... Which is one of the reasons I need so many florescent lights in there...

There isn't any sort of duct tape that will hold in a high humidity environment. BUT... The heavy duty liquid nails will...

[RodKirby]

When I had my Shed built, I was more concerned about noise (4-panel auto door). I bought 12 x "noise reducing" batts (3 per panel).

Each batt is uncovered fiberglass "wool".

I had to cut (stanley knife), about 2" off the end of each batt, but I could then just "pop" them in A reinforcing bar runs across the middle of each section and there is a lip running around each panel which holds them (loosely) in.

Not only kills the noise but also insulates the door, which faces West.