Insulate a Garage Door

How to Insulate a Garage Door

Insulate a garage door, and it will make a home warmer in the cold months, and cooler during the hotter months. And an insulated garage door make it much quieter when next to a busy street, than a non-insulated door. Insulating a garage door is much easier than many would think, and in most cases, it can be done in a single afternoon. But what type of garage door insulation do you purchase, and for what type of door?

Types of Garage Door Insulation

There are three main types of garage door insulation: batt insulation, foam board insulation, and reflective insulation. Batt insulation is flexible and often found in the exterior walls of homes. Typically, batt insulation is made out of fiberglass. The backing for this insulation tends to be made from foil or paper, which is an air and vapor barrier. The cost of batt insulation is around $0.30 per square foot, and the R-value is 3 to 4 for every inch of thickness.

Foam board insulation is a little easier to install and made from rigid panels made out of polystyrene. These provide a high insulation value for a thinner panel. They are R-3.3 for half inch thick panels or R-6.5 for one-inch foam panels. The boards are faced with vinyl or aluminum and cost about $0.63 per square foot.

Reflective garage door insulation is made of rigid boards with highly reflective aluminum foil on one or both sides of the material, which can be polyethylene bubbles and cardboard. This form of insulation reflects the radiant heat of the room, making it good for garages that tend to heat up in the summer or are in a hot climate. The R-value for this type of insulation is 3.5 to 6, depending on how it is applied. It is $0.42 per square foot on average.

Installing Insulation on Different Types of Garage Doors

Metal garage doors are able to use any form of insulation. Just cut the insulation to size and be sure to put fiberglass insulation with the paper or foil layer facing the outside. Foam board insulation just squeezes into the door’s frames.

Panel doors and wood framed doors require the insulation to be cut to fit and rigid insulation placed between the door frames. If added climate control is necessary for particularly cold or hot climates, use a double layer of the foam boards.

Reflective or foam board insulation is better for flat garage doors without a panel. Tape or glue the insulation to the door, or follow the directions from a kit.

Doorstop Weather Stripping and Bottom Seals for Garage Doors

Two forgotten areas for insulating a garage door include the weather stripping and the bottom seals for the doors. Nail the doorstop weather stripping at the top of the door jamb, starting at the top of the door. The sides should be mounted in the same way. If there is light still visible through the weather stripping on the sides, then install a spring-loaded hinge for the doors that presses them against the weather stripping.

For the bottom seal, open the garage door partially until you are able to see the bottom of the door. There should be screws on the bottom of the door and a seal track. Most installers will crimp the slots at either end of the track to keep the seal in, so be sure to open the crimps and slide out the old seal if it looks cracked or broken. Slide in a new seal and crimp the ends to secure it in place.