Do’s and Don’ts of Garage Door Insulation – Is It Worth It?

The garage is more than a storage place for your car, it is your crafting space, and maybe another entrance into your house. It provides shelter for all your outdoor stuff, which needs to go somewhere when the rainy season arrives, and can even be the place where you produce your homemade beer.

However, it isn’t uncommon for it to be neglected. Homeowners invest in their homes, front doors, surveillance and security systems, wall insulation, and others, but often forget how sensible the garage door can be. Burglars often pick it as their favorite brake-in point, as in many cases, the owners postpone upgrading or installing a new garage door opener and rely on old security measures to protect this second entrance. Flimsy or old doors that can easily be broken also contribute to the lack of security.

But there’s still another thing when it comes to the garage that can affect your budget and the comfort of your home, namely, its ability to maintain an optimal temperature inside no matter how the weather changes outside. The first solution that comes to mind in this situation is insulating the door. But things may not be as easy as you imagine, and, if you don’t take all the precautions, you may end up spending your money on almost unnoticeable differences. This guide will help you decide if making this step is a wise decision and provide you with essential information about the process.

Why Is Garage Door Insulation Important?

Is your garage sharing one wall with your home? This is enough for the draft and uncomfortable temperatures that build up inside the garage to wreck the thermal comfort inside your house. If your space isn’t insulated, the conditions inside it will fluctuate with the weather and affect it in various ways:

  • Convection – This phenomenon will make your space cooler in the winter, as it describes the movement of the warm air to the ceiling while the heavier cool air is pushed to the ground. The heat that reaches the attic creates a current that draws the cool air from outside. The same happens when the walls have gaps or air is escaping through openings around the door and windows.
  • Radiation – It is the way through which your space gets hot without coming in contact with the heat source. The sun rays heat up the roof, increasing its temperature and the temperature inside.
  • Conduction – Once the roof has been heated by the sun, the heat is transmitted to all the objects that come in contact with it. Thus, the walls become warmer, and the air’s temperature increases.

Another aspect is the noise, which can either break out of your garage doors when you are working inside and bother your neighbors or your family, or come from the outside if you are living in a highly-trafficked neighborhood. An extra layer on the door can act as a barrier against it and bring you more peace of mind.

What Are The Benefits?

It can seem like a big investment, but the advantages that result from this upgrade will actually make up for all the spent money. Here are some of the most important:

  • You will lower your energy expenses – If heat or cold air is invading your garage, it becomes a weak point in your heating or cooling system. It is enough for one wall to have a different temperature for your HVAC system to need to work harder to maintain the comfort inside the house. Moreover, if you have a door communicating with the garage, every time you open it, a wave of hot or cold air will find its way in. On the other hand, if this problem is solved, your installation will reduce its activity, and you will notice a decrease in energy costs. This will soon compensate for the initial investment and permanently reduce your expenses.
  • Your HAVC system will last longer – As the pressure that is put on it is reduced, the time it needs to work to bring the air to the desired temperature will be lowered as well. Plus, it won’t need to switch on and off as often as it did before, not to mention that a uniform temperature is more beneficial to any electrical unit.
  • You will enjoy upgraded security – Insulation means thicker doors that last longer and can protect your car and your home better. If the entry point is flimsy, it is easier for burglars to find their way in.
  • Your car will be protectedTemperature variations reflect on your car’s system, and this can be better noticed in the winter when the engine takes longer to warm up. Insulation can make a difference of up to 10 degrees, taking away some of the pressure that is put on it.

What to Consider Before Starting the Job

In some cases, this addition is almost mandatory, whether in others it may not worth the money at all. Here are some criteria you need to take into account before making the investment:

  • Climate – Insulation is usually a good purchase if you live either in an extremely cold or hot area. If the temperatures tend to reach extreme values in your state in the winter and/or summer, this will influence your home’s overall atmosphere. On the other hand, if you are lucky enough to live in an area where the winters are gentle and the summer sun has more of a warming effect than blazing over your home, then you should invest your money into something else, maybe improve your security system or upgrade your door opener.
  • The state of your garage – It would be a waste of money to insulate the door if the space is in poor shape, showing gaps through which the air can easily brake in. In this situation, you may need to think of an even bigger investment, which would include filling the gaps and maybe insulating the entire room.
  • Insulation type – If you have checked the previous factors and decided to follow through, you will need to decide on the materials that are going to be added to your door. You have two options:
    • Polystyrene – It is a common pick due to its waterproof capabilities and low price. Its structure allows for it to be easily shaped according to the door’s size. Moreover, it is fairly easy to install. On the other hand, owners who live in areas with extreme temperatures often find ii to be too thin and unable to contain the air inside.
    • Polyurethane – You are looking at a more pricey option, which, nonetheless, is worth all the money. This is a more complex synthetic polymer and has a denser and thicker structure, being more efficient against the effects of the weather.
  • Door constructionSome materials have higher insulation properties than others, so, if your door is old, it may be a better idea to replace it. Check for the following materials:
    • Wood – Today you will find models built of several layers of wood that offer excellent protection against the hot or cold air. If you invest in a high-quality, solid model, you will never have problems with temperature variations.
    • Steel – While wood may require more maintenance, there’s a simpler and more efficient solution, namely having your door built of steel. Once again, these units include multiple layers that act as insulators and are perfect for keeping the air tightly closed.
  • R-Value – This is a variable that measures the insulation’s efficacy. The higher the value, the better your door will act against exterior conditions. To understand the difference, a door that has been insulated can have an R-value between R4 and R18, while a regular door’s value is usually considerably lower. Nonetheless, you shouldn’t rely on this parameter only when doing your purchase. The truth is that there are far many factors that can influence it in real life, and the results can be very different compared with the measurements performed inside a lab. For example, the walls may have a lower R-value, while any gap or unsealed window will just reduce it even more. In this case, if too many factors act upon it, the best is to make sure first that the garage itself is a tight place and, only after, take care of the door.
  • Weather Stripping – It isn’t enough to add polystyrene or polyurethane panels on the inside of the door. You will need to make sure that the air cannot mover around it through uncovered openings. If you have had weatherstripping installed before, make sure they are in good shape. Otherwise, remove them and use foam or vinyl weather stripping to seal the gaps.

Is Sealing Between Garage Door Sections a Good Idea?

The most common models are sectional doors, which break into sections when the door opens. Well, the small gaps that leave the light enter inside your garage will also let the air circulate, so you can also use weather strips to cover them up. However, you should only coat the gaps that let the light in, as too many weather strips can put pressure on the hinges and, in time, lead to damage and costly repairs.

How Much Does It Cost to Insulate Your Garage?

The expenses can vary according to the type of insulation you choose, door size, and whether you are going to do it yourself or hire a professional. If you are willing to do the hard work yourself (which isn’t as hard as it seems, by the way), the costs will bring you up to $300, insulation and installation kit included, for a regular door. On the other hand, if a professional is handling this job, your costs can rise considerably, sometimes going up to $1,000 or more. It may seem expensive, but if you have never performed this job before or are not very good with manual stuff, spending extra could actually guarantee you that your investment isn’t a total waste.

Is It Worth The Money?

Few people think about insulating their doors unless they struggle with a real problem, so, in these cases, the money is usually well spent. However, as we have already explained, if the problem is bigger and the temperature variations aren’t necessarily caused by the poor insulation of the door but by structural problems in the garage’s walls, gaps, or openings around the windows, you should first handle these issues. The expenses will indeed rise considerably, but, afterward, you will be able to benefit from lower energy costs, increased security, and nicer temperature inside your house.

Recap: Do’s and Don’ts

When shielding your garage door, do:

  • Check if the garage is in good shape and air cannot get in through other gaps or openings
  • Pick an insulation material suitable for the climate in your area
  • Consider replacing the door if it is damaged
  • Use weather strips to cover the gaps around the door
  • Weigh the costs and turn this into a DIY project only if you have the skills

At the same time, when insulating the door, don’t:

  • Do it if your garage is unfinished or shows wall damage
  • Spend your money if you live in a temperate climate
  • Consider only the R-value and ignore all the factors that could influence it
  • Use weather strips to cover sectional gaps that don’t allow the light to pass. You are overdoing it, and this will put unnecessary pressure on the door.


Although shielding the garage door will change the way your space responds to weather changes, it is important not to have unrealistic expectations. Indeed, the pressure put on your HAVC installation and the car’s engine will be reduced, but your garage won’t turn overnight into a leisure space where you can invite your friends and enjoy a cool beer while watching TV. Even if the walls are thick, there’s still a huge door that allows the car to get in, which will never have the properties of a wall.

This being said, if you consider it is time for this investment, then wait no more. Do the measurements, get the materials, and start the job. You will thank yourself the next winter.