How to Use a Lighter to Find Air Leaks

It’s not a new concept, but Instagram content creator effectively demonstrates how to pull off the lighter hack in his viral reel. In the video, he explains that he suspected an air leak coming from the bottom corner of a door and subsequently used a light to confirm his suspicions. By carefully holding a flame along the door frame, he could see where the leak was coming from by how the flame moved. If the flame flickered or bent, air movement was present, indicating a draft. However, if the flame remained steady, the frame was well sealed.

He also points out that some light might shine through the gap, which may or may not be the case for you, depending on where in the house you’re checking or the outdoor brightness level. If it’s dark, a flashlight can help you see gaps more clearly after the flame indicates their location.

Before Starting the Search

A few more things to consider when searching for drafts include:

• Ensure all nearby doors and windows are closed to avoid unintentionally affecting the flame.
• Turn off any fans and the HVAC system to prevent interference with your inspection.
• Test all around the frame, including the top, bottom, and both sides, and use tape to identify any leaks so you know which spots to address.

It’s crucial to exercise caution around flames, especially when working around wood frames. Keep the flame far enough away from any material but close enough to be affected by drafts. It’s also best to try this hack when small children or pets are secure in another room.

How to Fix Air Leaks Around Doors

After you detect drafts, you can seal them using weather stripping, a door sweep, caulk, or corner seals. The repair not only improves insulation, thus keeping you cooler in the summer and warmer in the winter, but it can also save you a significant amount on your home’s energy bill. Use the following information as a guide to determine the appropriate method for fixing drafty doors, based on the location of the leaks.

Air Leaks at the Bottom of a Door

For a sizeable gap and a heavy draft, try a door sweep. These can come in plastic, but door sweeps are usually made of an aluminum strip with a rubber seal. Otherwise, you can likely get away with using a draft stopper, sometimes called a door snake, a fabric tube filled with sand that sits inside at the base of the door.

Air Leaks at the Top or Sides of a Door

Installing or repairing weather stripping around the frame is the most efficient solution, but there are various types to choose from. Opt for the type you already have—whether it’s felt, foam, rubber, or silicone—if you’re replacing a section. If the stripping is old and worn away, feel free to replace it with your preferred material. It might be possible to seal a small leak coming from a corner of the door with a bit of adhesive-backed foam.

Air Leaks Between a Door and Frame

Cracks between the frame and the wall should be treated with caulk. For a discreet seal, consider using a clear silicone option.

Alternative ways to eliminate door drafts include replacing a worn-out threshold, adjusting loose hinges, or investing in a storm door.

How to Fix Drafty Windows

If you discover your windows are the source of the draft, add weather stripping to the bottom of the sash or caulk around the perimeter. Believe it or not, heavy-duty curtains can help with insulation, so consider adding a set if your windows are currently bare. For those living in exceptionally cold climates, consider temporarily wrapping your windows in shrink wrap or using a window insulation kit to keep in the heat.