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Mid-Atlantic Door Group Inc. Distributors of Overhead Door Corp.

What You Need To Know About Insulated Garage Doors

Everything You Need To Know About Insulated Garage Doors

Every aspect of your garage should be properly insulated, including your walls, the ceiling, and your garage door. There are plenty of ways to insulate your garage to make it more energy efficient.

You may not spend a lot of time in your garage, but having it properly insulated protects your cars, tools, and stored belongings against weather and temperature-related damage. An insulated garage also prevents heat loss that causes your monthly energy bill to rise.

Is Your Garage Door the ‘Weakest Link?’

If your garage is well insulated but you’re dealing with a drafty garage door, it’s time to replace it with a door that will do the job right. A properly insulated garage door will regulate the temperature inside your garage. Just like insulating your home, an insulated garage door will help keep extreme heat and cold outside where it belongs.

If you live in an area with extreme weather, your garage door should be strongly insulated. Thankfully, manufacturers use a rating system called ‘R-value’ to tell consumers how much insulation their doors provide.

Understanding R-value

In the construction industry, a term called “R-value” is frequently used to rate the “effectiveness of insulation in stopping heat flow opposite of conductance.”

For example, the average building will have an R-value of 20. By installing fiberglass insulation, this rating can be improved to 35.

  • R-value fluctuates – Due to the different methods used between manufacturers, the R-value of a garage door won’t be absolute, although it will be fairly accurate. If you’re looking at a garage door rated R-18 and you find another company offering a similar door rated R-20, don’t just blindly make the purchase thinking you’re getting a better deal. Both doors might provide the same level of insulation. Find out what materials the doors are constructed from and make your decision based on all the facts.

How Garage Doors Are Insulated

insulated steel garage door


Thermacore® Collection Insulated Garage Door

Most garage doors are insulated with layers of polystyrene, also known as Styrofoam, which comes in varying densities. The denser the material, the more insulation it provides.

The highest rated garage doors use polyurethane sandwiched between layers of steel. Polyurethane is like liquid Styrofoam in a spray can. It can be easily sprayed into cracks and used to seal doors and windows. Since it’s liquid, it fills the space quickly and fully.

Polyurethane is superior insulation. According to a 2005 National Institute of Standards and Technology (NIST) study, polyurethane insulation reduced air leakage by up to 83%, and reduced energy consumption by up to 40%.

Manufacturers also increase the thickness of a door to increase insulation, although even a three-inch thick door won’t beat a thinner door insulated with polyurethane.

Garage Doors with Windows

An insulated garage door is great, but what about adding windows? Regular windows greatly reduce the R-value of your door, and insulated windows are expensive. It’s nice to see out of your garage, but consider what you’ll be sacrificing.

If you tend to get snowed in, having a garage door with windows might not be the best option unless you can easily afford insulated windows. On the other hand, if you live in a mild climate where you can open your garage door in the winter without freezing, windows can add some charm to your home.

Consider More Than R-value When Buying a New Door

All garage doors have an R-value, and although you want a door with a higher value, there are other factors to consider, such as construction. The weather stripping, bottom seal, and sealing joints between the panels should all be considered when selecting your garage door.

How often do you open your garage door?

You could have the highest rated garage door in the world, but an open garage door has an R-value of zero. This is why it’s important to select your door based on more than just R-value.

If you don’t open your garage door very often, you’ll benefit most from a garage door with a high R-value. Since your garage door will be closed most of the time, you’ll reap the full benefits of its R-value. Your closed garage door essentially becomes a wall.

If, however, you open your garage door often or leave it open for extended periods of time while you do shop work, then R-value won’t be as significant for you. It’s important, but remember that the R-value only applies to a closed door.

Insulated garage doors help you save on energy costs $$

Unless you turned your garage into a spare bedroom, you probably didn’t install a heater vent inside. Even so, the heat from your home can escape into the garage and get sucked right out through a poorly insulated garage door. This energy loss can keep your heater on for extended periods of time. The inside temperature won’t reach the thermostat setting to trigger the automatic shut off.

The amount of heat escaping through your garage may not be enough to make a significant impact each month, but will add up over time. The key to saving on energy costs is to reduce your energy waste everywhere you can because it does add up. Consider that saving just $10/month on your energy bill saves $120/year. That money could be used for a home repair, taking your family out to eat, or paying off debt.

Want To Learn More?

We carry a full line of insulated residential garage doors in various materials. Our best selling collection is our Thermacore® Collection. Thermacore® Collection steel garage doors feature premium insulation construction and design which provides maximum thermal efficiency and reduced air infiltration for your garage space.

To find out more about how an insulated garage door can protect your car and your belongings, and reduce your energy bill, contact us today. We’ll put you in touch with one of our local experts right away. We offer virtual and in-home sales estimates at your convenience.

About The Author | Natalie White


Natalie White is the Health and Wellness Coordinator and Marketing Assistant at Mid-Atlantic Door Group, Inc. The company opened in 1973 and now consists of (3) official Overhead Door™ Distributors and (7) warehouse locations throughout Maryland, DC, Virginia and Pennsylvania. Natalie married into the door industry, joining her husband's family owned business in 2014. Surrounded by door knowledge, Natalie has found her niche in employee wellness, as well as customer service and call-tracking to help strengthen the company's marketing efforts.