How To Insulate Around Window Air Conditioner

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A study called “There Are Holes in Our Walls” shows just how important insulating around window air conditioning is to homeowners. In this study, conducted by the Urban Green Council, it was discovered that the amount of money lost each year, thanks to the fact that most people don’t know how to insulate around window air conditioners properly, is nothing short of staggering.

When it comes down to insulating around window air conditioners, you need suitable materials like spray foam or caulk that can easily be retrofitted to snuggly get into the available gaps. You want to use a flexible foam insulation material after you have identified all gaps and holes.

Read on for more information and how to properly insulate around window air conditioner units.

Why Should You Insulate Around Window Air Conditioner?

Apart from the fact that you could end up saving hundreds of dollars on your energy bill each year, as highlighted by the Urban Green Council report, there are several other excellent reasons you should insulate around your window air conditioner. These include:

• To avoid overworking your AC
• Minimize the number of repairs your AC needs in a year
• Create the right air conditioning within your home

In many cases, the window AC you buy will probably come with insulation foam that you can easily cut to fit your windows. There are also some window ACs that come with plastic curtains that tend to slide out sideways.

While these are useful in their own way, they won’t necessarily keep the cool or hot air from coming in and going out of your home. They are, however, perfect for keeping insects and other debris from entering the house.

Tips On How To Insulate Around Window Air Conditioner

While there are several products such as foam you can use to insulate your window AC unit, one of the most effective methods is spray foam. That’s exactly what we are going to use here.

• Note: Spray foam sets almost immediately and can be rather difficult to remove. So, if you intend to follow these tips and use spray foam, you need to be very careful where and how you apply it.

That being said, here are the simple steps you need to follow when using spray foam as a means to insulate your window AC unit.

Step 1: Inspect The Window

This should be the first thing you do – inspect the window to see where the cracks can be found. This involves looking on top of the unit as well. Many people ignore this part because they feel the window is secure enough; after all, it’s holding the AC in place. However, there could be a tiny space between the window and the AC unit, and this space can let outside air in and the warm air inside out.

Step 2: Check The Window Sash

The window sash area is particularly problematic. The accordion side flaps could be misaligned and not filling up the cracks properly, or the flaps could very well be worn out and need replacing. If there’s just a little crack, you could probably seal that up with some duct tape. It won’t be pretty, but it will do the trick.

Step 3: Make Sure The Unit Is Clean

It’s best to ensure that your unit is clean and free from dust, debris, grease, or any other gunk that might keep it from properly adhering to the window or eventually breaking down.

Step 4: Bring Out The Caulk Gun

Caulk is one of the best materials to use when you want to both seal cracks and hold your AC unit in place. Caulk is best used outside of the unit – this helps to hold it in place and reduce the chances of any air flowing through the spaces between the unit and the window.

If you’re going to use caulk, you might want to make sure that you do so when the weather is cool and dry. It’s advisable to go for anything around the 40-degree Fahrenheit mark. You can also use rope caulk along the edges of the window and the air conditioner unit if there are still some spaces.

Step 5: Bring Out The Spray Foam

Finally, spray foam insulation is one of the most effective materials you can use to seal up any gaps between your AC unit and the window. However, as effective as this material is, you need to use it with great care since it sets very quickly (a matter of seconds), and once it sets, it’s extremely difficult to undo. It will, however, seal up all those gaps. That’s why you should only use this option if you don’t intend to move your AC unit during the wintertime.

These are some of the most effective ways on how to insulate around window air conditioner. There are other methods, but they are often quite temporary and don’t look good. If, however, you aren’t comfortable doing this on your own, you could always hire a contractor or a professional AC installer. Never leave any gaps between the window and the AC unit.