Air leaks use up oxygen and displace it with carbon dioxide and other gasses that aren’t good for you to breathe. This is a waste of energy, and it can also lead to health issues like watery eyes and coughing fits.
To do this test, choose a windy day and turn off any combustion appliances or exhaust fans. Then move a piece of paper around the most common places for air leaks. If the paper wavers, there’s a leak.
Check for Cracks and Gaps
Gaps around windows allow warm air to escape during the winter and cold air to enter during the summer. This wastes energy and raises your cooling costs. It also allows unwanted insects and spiders to enter your home.
Fortunately, air leaks are fairly easy to fix. A quick visual inspection can reveal many of the most common problems. Look for obvious cracks and gaps in areas where two different building materials meet (corners, where the foundation meets the bottom of the siding, and the spot where a water spigot or dryer vent is attached to the house). You should also check areas where pipes or wires enter through walls or ceilings, and around door and window frames, electrical outlets and switches, baseboards, and recessed lighting fixtures.
For a more thorough check, shut doors and windows and turn off furnaces and fireplace flues. Then light an incense stick and move it around common leak sites. If the smoke wavers or feels like it’s being blown out of or into the room, there is a draft. You can also shine a flashlight at night over potential leak sites while a partner observes from outside the house. Large cracks will show up as rays of light shining through the wall.
If you want to be more scientific, try the building pressurization test. This involves closing all windows, doors and combustible appliances, then shining a flashlight at the potential leaks while a partner observes from outside the home. This method will only detect large leaks, though.
Inspect the Seams
When air leaks into your home, it also carries with it moisture and allergens. This can lead to problems like mold and dander, as well as exacerbate existing health conditions. It is important to inspect your home regularly for air leaks and make any necessary repairs. You can find leaks in many places throughout your home, but the most common are around doors and windows, attic hatches, recessed lights, plumbing vents, ceiling fans, and electrical outlets.
Larger leaks can be detected by feeling with your bare hand. On a cold day, place your hand around the outside of the window and door seams to see if you feel any draft or change in temperature. You can dampen your hand to make it easier to detect the changes in temperature. The same method can be used around other areas of the house such as electrical outlets, light fixtures, baseboards, crown molding, and phone jacks.
A simple stick of incense can also be used to locate air leaks that are smaller than those you can detect with your hands or a candle. To use this test, first depressurize your home by turning off the water heater, furnace, and any combustible appliances. Then, hold a lit stick of incense near all suspected leaks. If the smoke is blown inward or sucked outward, there is a leak.
Use a Smoke Pencil
There are a number of ways to check for air leaks at home. Using a smoke pencil is one of the easiest and most reliable methods. Unlike other smoke sticks or puffers, this handheld tool does not contain any dangerous chemicals or flammable materials and is safe to use in tight spaces.
The smoke produced by this pen-like device is cool and nontoxic and it will help you visualize the direction of the draft. Simply place the nozzle of the Smoke Pencil One over an area that you suspect has a leak or a draft and pull the trigger to generate a traceable smoke trail. The smoke will indicate if the draft is blowing into your space or if it is being sucked out. This can be used for many applications including finding drafts around windows and doors, identifying air movement in HVAC ductwork joints, verifying ventilation systems, testing negative or positive pressure in clean rooms or isolation chambers and even K9 scent detection training.
This smoke pencil has an adjustable nozzle that allows you to control the amount of smoke it produces. Pulling the trigger harder creates a thicker plume of smoke, while pressing it gently allows you to produce only a small amount of smoke. This unique feature makes this draught detector ideal for use in the tight spaces around windows, doors and vents.
Hold a Piece of Paper
Although air leaks may seem like a minor nuisance, they can cost you a lot of money in the long run. Fortunately, there is an easy way to find them, even without any fancy equipment. Hold a piece of paper near potential gaps, such as around door or window frames or electrical outlets. If you feel a breeze, or if the paper moves slightly in one direction or another, it means there is a draft in that area. This technique also works well for checking the integrity of insulation in your attic.
The paper will move toward the flow of air, demonstrating Bernoulli’s principle.