How to Insulate a Garage

There are several insulation types you can use, including batt or blanket, blown-in and spray. Spray insulation is best performed by a pro and requires a good bit of setup in advance. For the purposes of this discussion, we'll cover batt and blanket.

Beyond the typical functions of keeping heat, cold, and dampness in or out, insulation can also help you keep the din of the outside from entering your garage and the activities you pursue in that space from escaping to your neighbors or the rest of your house. A new option on the market for batt or blanket insulation adds a slight soundproofing quality. This is an extra layer added with the vapor and is no more difficult to install than typical batt and blanket insulation. Remember that with insulation, it's all about the R value – the higher the better. This will, however, be limited to the thickness of your walls.

To prepare, determine the area of the space you plan to insulate and add 10 to 20 percent to account for mistakes and odd spaces you need to fill. Be sure to count the spaces above doors and windows. Measure the space between joists and studs to determine the width of the insulation you need. A basic rule of thumb is that these are spaced 16 inches on center, but this can vary widely.

Select your type of insulation. While fiberglass is most common for blankets and batts, there are many natural material options available. Whichever type you select, finding one that isn't made with formaldehyde is a top priority.

Take your square footage figure and divide it by the square footage that each roll or package of insulation will cover. This will determine how many packages of insulation you need. Install as directed, typically cutting to fit and using a staple gun to attach the vapor barrier to the studs.

If you’re adding new garage doors, be sure to install insulated options. If you’re using old, uninsulated doors, pick up a retrofit kit that add insulating panels.

To keep the floor a bit more comfortable in the cold months, add interlocking foam or PVC mats. They'll offer a slight amount of insulating effectiveness, but are more about keeping the floor warmer and cushier underfoot.