View Full Version : garage door insulation

09-01-2012, 11:58 AM
I am looking at insulating my garage door (in LA so I am worried about heat and less about cold). Looking at an R5 and an R8 solution. R8 would run about $140. R5 about $85. I am thinking it would take a LOT of heat savings to pay back that$60 or am I way off base?

09-01-2012, 01:40 PM
Is the garage conditioned space? First thing I'd look at is making sure I had a good threshold gasket and flexible seals along the other three sides.

Are the walls in the garage insulated? If not, it's a waste of time to insulate the door.

09-01-2012, 02:42 PM
quote; If not, it's a waste of time to insulate the door.

Not really. If the door is in the sun, it will absorb the heat and transfer it to the garage, and a 16' garage door is a HUGE radiator.

09-01-2012, 04:10 PM
If the garage walls are insulated, then yes, it's worth insulating the door, but fix the air infiltration while you're at it. If they aren't, the heat can radiate out the shady side as well as in.

Is the door metal or wood?

Gary Swart
09-01-2012, 10:23 PM
I have a fairly large garage/shop with 2 overhead doors. Wall have 2x6 studs with batt insulation behind drywall. 12' ceiling has 12" blown insulation. No windows and 2 walk in side door, steel coated. The overhead doors are insulated with strips of 2" foam. There are air leaks around these doors, but still with 100 degree plus days, the interior is 20 degrees cooler that the outside. I maintain 55 degrees inside during the winter with an overhead gas furnace. I can boost the inside to 70 or so in just a very few minutes. I know it would be wise for me to seal around the overhead doors better, but my gas bill (combined with all gas appliances in the house) is quite reasonable so I'm not too motivated.

09-02-2012, 06:22 PM
IF you have at least some walls insulated, it certainly makes sense to insulate the garage door.

10-31-2012, 05:05 AM
In LA it would be pretty common for the garage NOT to be conditioned, and in fact to be ventilated.....intake vents at the level of the bottom plate, and soffit or roof vents up high. Nonetheless, if the door faces south or west, you do get a lot of heat gain from it, so insulation would help.
Why do you need the garage to be cooler? Is it a shop? How often is the door opened??