So here are the steps to getting it done.
There are a couple of options when it comes to the type of insulation you can use. We decided on the foam panels. It gives a nice finished look once installed. We weren't able to find these at our local home improvement stores but we did find them at a garage door specialty store and were able to buy them there. They can also be ordered online.
Before you go to buy your insulation panels, you will need to know the height of your garage door panels. They generally come in about four different heights (18", 21", 24", and 27"). This will allow you to determine the size panels you need.
Next, you need to know how many insulation panels you will need. Most garage door widths are pretty standard. We told our guy we needed enough to do (1) two-car garage door and (1) single car garage door.
Here are what the panels look like.
Now it's time to measure how wide your panels need to be.
On our garage door, the two end sections were different widths than the two middle sections.
Using your tape measure, measure off this width onto the insulation panels...
and use your straight edge and box knife to cut them.
It doesn't cut all the way through, so you can gently "snap back" the panel for a pretty clean break.
Now it's time to install. Slip the bottom in the "notch" on the garage door panel and gently bend the insulation to pop it into place.
For a finished look, you can install these end pieces. They install in a similar manner (these were pre-cut to the height of the panels)
We have noticed a definite difference in the temperature of the garage - about 10 degrees F warmer than the exterior. And it's much quieter now (the stereo sounds better, too!).
It's not the most glamourous upgrade but it makes working in the garage in the winter much more bearable!