What is the Best Garage Door Insulation?

The purpose of insulating your garage door is to block out sound and help regulate temperature. It can help to decrease your energy bill costs because it traps valuable heat in, as well as cool air. A garage door that is properly insulated can also be a good barrier against outside light and noise. Garage door insulation is something that you can do yourself and it won’t cost a great deal. To benefit from the right type of insulation for your needs, read on.


You will probably spend about $200 to insulate a double garage door properly, but you need to take proper measurements. This will help you estimate how many boards you need. Fiberglass is particularly flexible as far as insulation goes, and is mainly stuffed into the walls. This material is beneficial in protecting your garage from any harmful air from the outside. This method is also rather cheap, at about 20 to 40 cents for every square foot.

The fiberglass is also backed by foil to provide more sealing protection and is the most popular type of garage door insulation. Fiberglass can irritate the skin and eyes if touched too much so be careful when working with it. You can buy a plastic-covered fiberglass bat, which can also add to the aesthetics of otherwise messy insulation.

Spray Foam

If you have a large area to work in that has a lot of small spaces, spray foam will work the best. It expands over the area so you can cover a larger part with less material. One of the main advantages is that it provides an airtight seal that you won’t get with most other garage insulation materials. Most spray foams are also resistant to certain bugs and protect the garage door from mold. Although this material is a better sealant, it can be more costly to use than other options.

Another thing to look out for is using too much or too little at a time. If the foam expands too far, you will need to use a box cutter to remove those excess pieces. Spray foam is also not resistant to age, and it will start to shrink the longer it sits. You may find that you need to do regular repairs or even re-insulate the area after a few years.


Insulation has a value as to how well it’s sealing the area. You want an R-value of between three and four which will be about half an inch to one inch thick. Polystyrene garage door insulation comes pre-cut in the right thickness. The material is similar to Styrofoam so it’s easy to work with and cut the pieces you need. Polystyrene insulation is best suited for thin walls, so garage doors are a perfect fit. It’s one of the most affordable options out there, but you have to cut the pieces yourself.

Even with its high R-value and noise reduction ability, polystyrene can be eaten away by insects such as mealworms. It’s relatively easy to get into and these bugs are attracted to the material. They have a unique ability to turn polystyrene into carbon dioxide, and their stomachs recycle the material into organic waste.


This reflective foil acts as a radiant barrier, which protects the garage space from heat and the cold. These aluminum pieces come in rolls that are applied to either side of other insulation methods like cardboard. They provide additional insulation that is particularly helpful in hot climates because of the heat radiating effect.

Reflective foil is a very easy material to work with as well as being easy to keep clean. Just a damp cloth will remove most stains. For insulating your garage, it’s another great cost-effective option like fiberglass. If you seal the garage door off just right, it can be used as a soundproofing material.

Combined Methods

The three most common garage door insulation materials are polystyrene, fiberglass, and aluminum, and you can use spray foam with each of these. There may be small gaps where the air is getting through, so making sure that each part of the garage door is airtight is important. Add a small amount of spray foam and any open spaces will be sealed as it expands.

If you are worried about what material to go for or how to go about insulating your door, look for an insulation kit. Most of them use reflective aluminum foil or foam boards and will come with instructions as well as the correct tape or glue you need to secure it.

Insulating a garage door is a worthwhile effort to go through. You can save money by not using other heating and cooling devices with the right insulation material such as these four. It will keep your garage at a comfortable temperature and make it a more comfortable space in your house to spend time in.