How to Find Air Leaks in Your Home

Man fixing air leak with caulk gun How to Find Air Leaks in Your Home

If you want to keep your home as energy efficient as possible, one of the best things you can do is check your home regularly for air leaks. The seals around doors, windows, and other areas of your home that lead to the outside can break down over time, so what was once a perfectly fine air-tight seal might not be so effective as it once was. Since we’re sure you have other things you’d rather spend your hard-earned money on than high energy bills, here are some ways you can check for air leaks around your home.

Since doors and windows are two of the main places air can escape through, those are good places to start. Other important places you should check for air leaks include electrical outlets, light switch plates, recessed lights, outdoor water faucets, baseboards, mail slots on doors, dryer vents leading outside, doors leading to attics, around your home’s foundation, the area where your chimney meets the side of your home, and where cable and phone lines enter the home. If your home has skylights, don’t forget to check around them, too.

First, visually inspect these areas to see if there are any obvious gaps or signs that the caulking or weatherstripping has become worn out. Simply putting in new caulking or weatherstripping might do the trick. When checking windows, try seeing if you can rattle them. If the panes of your windows are able to shift, you might be better off getting some vinyl replacement windows instead. Vinyl replacement windows would also be a good idea if it’s been a very long time since your windows were last replaced since they might be more energy efficient than your current windows.

Ideally, you’ll want to check for air leaks on a cool, windy day since those conditions will make it easier to locate leaks. Before you get started, shut all your windows, doors, and fireplace damper if you have one. Turn on any exhaust fans to direct as much air out of your home as possible and turn off your furnace and air conditioner so you won’t have to worry about air coming from them interfering with your tests.

The colder it is outside when you look for air leaks, the more apparent it will be if you have an air leak. You should be able to feel any drafts with your hand. But if you’re checking for air leaks on a warmer day where drafts won’t be as immediately apparent, you might want to use a laser or infrared thermometer to detect changes in temperature around your doors, windows, and other areas that might be prone to air leaks. Many people also like to take a lit candle or incense and move it around close to areas that are prone to air leaks. If there is an air leak, the flame of the candle or the smoke from the incense will change direction. If you decide to try the candle or incense test, just be very careful not to drop it as you look for leaks.

Another option is to have a professional come out and do a blower door test. With this option, the person you hire will come out and attach a giant fan to the door of your home to blow all the air from your home outside. When this happens, the only air coming into the home will be coming from air leaks so the contractor will go through your house and try to find them.