Air leaks take energy to heat and cool a building, which drives up utility costs. This article discusses some ways to find and fix these leaks.
Large leaks can often be detected by simply putting your hand near the seams of windows and doors and feeling for a draft or drop in temperature. Wetting your hand helps you feel changes in temperature more clearly. Other techniques involve depressurizing the house and using smoke sticks, incense, or a flashlight.
Look and Feel Around Your Windows
Air leaks around windows are a common problem that can lead to higher energy bills. These leaks allow warm air to escape during the winter and cool air to enter, causing your home to shift in temperature and creating a draft. Thankfully, there are a few easy ways to spot air leaks around your windows. You can use a stick of incense, the dollar bill method or hire a contractor to run more advanced tests such as a blower door test where your house will be depressurized to discover where leaks are occurring.
Before you start looking, make sure your windows are closed and turn off all exhaust fans in your home. Then, walk around your home and hold your hand against the sides of your window frames, electrical outlets and light switches to feel if any cold air is coming in. This trick is easier in the winter time when it’s colder outside. If you can feel a draft, it’s likely that air is leaking and you should check out window replacement. Leaving this problem unaddressed could cost you a fortune in higher energy bills.
Light a Smoke Stick
While you can use your senses to locate air leaks, there are a few additional tools that can make the process easier. One of the simplest is to light a stick of incense or a candle and move it around potential leakage areas. If the flame wavers or is blown by an unwanted draft, this can be a good indication of where a leak is located.
Another option is to use a smoke pen, which can generate a stream of non toxic white smoke that can be directed where it is needed. This product can be used for air flow studies and leak testing in wall outlets, recessed lighting fixtures, vents, etc. It is a safe and easy to use tool that requires no messy ash and can be extinguished by replacing the protective cover. The wick portion stores safely inside the barrel of the smoke pen when not in use.
This hand-held device is also popular with HVAC Technicians, Energy Raters, DIY Home Repairman, Contractors, Photographers and K9 Nose work trainers. It produces a thin, dense stream of smoke that reacts to the smallest of drafts and is ideal for finding air leaks around ducting seams and joints, exhaust hoods, laboratory equipment and for testing negative or positive pressure in clean rooms, isolation chambers and hospital isolation units.
Turn on All Exhaust Fans
When air leaks in and out of a home, it can waste energy dollars, make the home drafty, and lower indoor air quality. In addition, it can increase the amount of dirt and dust that settles in the home, which aggravates allergies.
When you turn on a bathroom or kitchen exhaust fan, it pulls hot, stale air out of the room and propels it outdoors. But if the fan isn’t properly installed, it can also propel air into other rooms of your house and cause your energy bills to rise.
To check for this problem, close all the doors and windows in your home. Then light a candle or use incense. Hold the candle or incense near areas you suspect are leaking air, such as door and window frames, baseboards, and electrical outlets. If the flame wavers or moves erratically, it’s an indication that there is unwanted air movement. This test is also useful for detecting a draft near a stove or fireplace. If it’s too cold outside, you can try using a thermal imaging camera to find the location of the leak.
Shine a Flashlight
Many hardware stores sell devices called “leak detectors” that help you find air leaks by emitting a light or sound when it encounters a leaking area. These can be very helpful in locating hard-to-see leaks, but they also tend to be quite expensive and require professional installation.
A more budget-friendly option is to perform a simple home test to detect air leaks. Choose a windy day and turn off your air conditioner, furnace and any exhaust fans that blow out through your house’s walls or roof. Next, close all your doors and windows and shut fireplace flues. Light an incense stick and pass it around the edges of any window or door frames that face outside. If the smoke wavers or is blown inward, you have an air leak.
Another good trick is to shine a flashlight at night over any potential gaps from inside the house while a friend or family member stands outside and watches for rays of light coming through. This method is especially useful for spotting large cracks, such as those around your attic hatch, basement walls, chimney, wall-mounted air conditioners, recessed lighting and plumbing vents.
Listen for Drafts
While you can often feel air leaks by running your hand around window and door frames, there are other ways to locate leaking gaps. The best time to check for drafts is on a windy day, as the colder air will help you feel any breezes or whistling sounds of escaping air.
You can also use a smoke pencil air detector or perform a blower door test, which involves closing off all vents and exhaust fans while using a powerful fan to depressurize the area. This forces outside air into cracks and crevices, making it easier to spot leaky areas.
During this test, you can place a sheet of paper, toilet paper or newspaper near suspected leaky spots and see if it wavers, which indicates that there is an air flow through the gap. If you prefer, you can use a stick of incense to light and hold up to suspected leak areas to see if the smoke moves or is sucked into the room. You can also buy a variety of handheld leak detection devices that are designed to locate leaking holes and seal them with caulk or foam weather stripping.