Pressurization Test

Building Pressurization Test

If you are having difficulty locating leaks, you may want to conduct a basic building pressurization test to increase infiltration through cracks and leaks, making them easier to detect:

Turn off all combustion appliances such as gas burning furnaces and water heaters on a cool, very windy day.

Shut all windows, exterior doors, and fireplace flues.

Turn on all exhaust fans that blow air outside, such as bathroom fans or stove vents, or use a large window fan to suck the air out of the rooms.

Light an incense stick and pass it around the edges of common leak sites. Wherever the smoke wavers or is sucked out of or blown into the room, there's a draft. You can also use a damp hand to locate leaks; any drafts will feel cool to your hand.

If you don't want to turn off your furnace, you can just turn on all your exhaust fans to depressurize your home.

Other air-leak detection methods include the following:

Shining flashlight at night over all potential gaps while a partner observes the house from outside. Large cracks will show up as rays of light. Not a good way to detect small cracks.

Shutting a door or window on a piece of paper. If you can pull the paper out without tearing it, you're losing energy.