The latest extreme cold snap finally inspired us to research options for insulating our garage doors, which are thin metal metal panels - no air space, no insulation whatsoever. In the winter the garage becomes an icebox, and by extension so do the connecting rooms: adjacent dining room, and office spaces over the garage.
And after, using the Owens Corning Garage Door Insulation Kit.
It took roughly 1 1/2 hours to do each door, which included time to clear the garage and find a place to trim the insulation to size where it wouldn't be laying in a puddle of snow/ice melt. We found the kits at Home Depot for about $55 per door.
So far I'm pleased with the results. The doors rattle less when opening/closing, and it does seem to already be keeping the garage warmer, but I'll now for sure in a few days when we get another cold snap. My hope is that it will cut down on energy bills and pay for itself within a few heating/cooling seasons. We'll see.
As expected, our trip to Home Depot was far from satisfying. In addition to buying these panels, we made a second trip to pick up some plywood to finish a basement shelving project. 95% of the non-furniture grade 2' x 4' sheets of plywood (which still cost about $13 each) were so warped they were completely unusable. I brought this to the attention of an employee. She just blinked at me and said, "that's how they come." Interesting. I had thought they were warped because they were shipped and stored improperly, but apparently Home Depot buys warped plywood to sell to its customers. Or... maybe this is more evidence that they staff their stores with nincompoops.