Air leaks in your home are a major cause of high heating and cooling costs. Finding and sealing these leaks will significantly reduce energy consumption in your home.
To find leaks, on a calm day, close all doors and windows and turn off fans and heaters. Walk around and inspect the edges of doors, windows, baseboards, electrical outlets, and plumbing penetrations for drafts or temperature differences.
Hand Test
One of the most basic ways to find air leaks is simply using your hands. On a cold day, close all exterior doors and shut off any fans or vents in your home. Then walk through the house and place your hand around the edges of windows and doors, bathroom and kitchen vents, and fans. If you feel cold air on your hand, there is a leak. This test is also useful for discovering larger leaks in the house, such as gaps between baseboards and crown molding, or around electrical outlets and light fixtures.
The dollar bill test is another simple way to check for air leaks in your home. During the day, place a dollar bill in a window. If the bill slides out easily, there is a gap between your window and frame that should be sealed.
In addition to visual inspections, you should also inspect the crawl space and attic. Look for cracks and openings, as well as deteriorated caulking or weather stripping. Also, listen; sometimes leaks make a hissing sound that can be heard.
Candle Test
In addition to visual inspection, many homeowners can use a simple candle or stick of incense to pinpoint leaks. Hold the incense or candle close to potential leak sites, and watch for smoke that drifts away—or is sucked inward—as the outside air passes through the gap. Alternatively, you can try using a smoke pen (also called a smoke pencil)—it produces similar results but isn’t as much of a fire hazard.
On a calm day, with the air conditioner and furnace turned off, run your hands along window frames, door frames, baseboards, electrical outlets, crown molding, recessed lighting and phone jacks to feel for drafts or temperature differences. Wet your fingers to make it easier to feel the difference.
For a more scientific approach, perform a burn test on a freshly made tester candle that represents your intended product. Clearly mark the wick, fragrance and container used to easily compare results later. Also be sure that the candle has fully cured—it may need up to 2 weeks for waxes to completely harden. It’s also a good idea to conduct your burn test in an environment that isn’t prone to drafts.
Incense Test
Incense has been used in various cultures for religious ceremonies, aromatizing and other purposes. When burned, it produces fumes (smoke) containing particulate matter, gas products and many organic compounds. These include volatile organic compounds such as benzene, toluene, xylenes, musk ketones and musk ambrette, polycyclic aromatic hydrocarbons and aldehydes.
Like second hand smoke, these pollutants can cause respiratory irritation. In addition, incense smoke can negatively affect the microbiota of the oral cavity.
To perform the incense test, choose a windy day and shut off all combustion appliances. With the incense stick lit, walk around the house passing it over doors and windows to see if you can detect any air movement. If the smoke shifts suddenly or disperses, this indicates an area of draft or leak. The more air leaks you can find, the more energy you stand to save.
Paper Test
During the winter, air leaks are one of the biggest reasons for high heating and cooling costs. Air sealing and insulation upgrades can greatly reduce your energy bills. If you suspect your house has air leaks, it is important to find them and fix them. There are several ways to find air leaks, including visual inspections and using the Paper Test.
This paper test uses the ability of an essential oil to evaporate off a piece of paper. The oil’s evaporation rate indicates the purity of the product. The problem is that this method fails to account for many types of adulteration. Heavier oils like vetiver can’t be evaporated by this test, and there are many other chemical additives that can be used to dilute essential oil.
To perform the paper test, turn off all the lights in your home and have a family member stand outside near the gap or crack you suspect. Have them shine a flashlight in the area and look for light coming through the gap or crack. If the light can make it through, there is an air leak.
Seam Test
Air leaks cause a lot of energy loss, and locating and sealing them can significantly lower your utility bills. A higher than usual energy bill may be a sign that new leaks have developed. Other signs include rooms that feel drafty or hot and cold.
Close all the doors and windows in your home, and turn off fans, humidifiers and other appliances. Then use your hand to feel for unwanted airflow around the edges of doors and windows, light switches, electrical outlets and plumbing fixtures. You can also wet your hand to make it easier to feel air flowing through the gaps and seams in upholstered furniture and curtains.
If you’re not able to find any leaks with your hands, it’s time to get creative. Some air leaks can be heard, especially when the wind is blowing. You can try listening for the hissing sound that air makes as it escapes through a leak, but this is not always reliable and requires that you be in the right place to hear it. Using a stethoscope or similar tool is more accurate.