Interestingly this is one of the most commonly asked questions by homeowners who are in the market for a new garage door. Many have yet to make up their mind because they are considering buying an insulated garage door, which can be slightly more expensive than a non-insulated one.

In this article, we will attempt to answer this question based on a number of factors. After all, everyone’s home and garage requirements are different.

What is the Garage Used For?

As mentioned earlier, some people may use their garage as more of a storage unit; others may keep tools and use it as a workshop. Also, some garages may be separate from the house while others are a part of it. Generally, speaking, if your Garage Door is attached to the home, you’ll want to buy an insulated door with an R-value of around R-12.

The other important factor to consider is if the garage is already insulated? If it is already well insulated with no leaks, then choosing a garage door of an R-12 resistance will work best. You can also choose slightly lower insulation of around R-6.

Now, if the garage is used for parking your car during the winter or you use it to store items, then having minimum comfort levels is fine. In that case, an R-12 should work, but going higher in colder climates will make the garage door more comfortable.

If the garage is used as an extension of the main home, i.e., as a playroom for the kids or a gym, then a higher insulation rating will make sense. You will want to get a garage door that has at least an R-16 level insulation.

Types of Garage Door Insulation

Currently, there are two types of insulation, polyurethane, and polystyrene. If you want the best thermal resistance, then Polyurethane is the best. It offers excellent insulation per inch of thickness which is twice of polystyrene. Furthermore, polyurethane adds strength because it adheres to the surface of the door, making it denser and consequently sturdier.

Polystyrene is usually slipped in between the door instead of it being injected. So, think of it as a kind of sandwich. Usually, the insulation goes within a steel door. Polystyrene is used outside of the insulation industry, like for making disposable cups and packaging material. Though it does not provide the best insulation per inch, but works out to be cheaper.


An insulated garage door can help reduce your energy bills for both heating and cooling during the summer. However, if your present door is also insulated, then make sure to first get it professionally inspected. If there are cracks or gaps in the insulation, get those fixed before considering a new door. That said, if you are in the market for a new garage door, an insulated door makes the most sense for the majority of homeowners.