The No. 1 reason that homeowners call A.Johnson is for comfort-related issues. The second reason is high utility bills. Often, both problems are caused by air leaks in the home – a problem that can be remedied with air sealing. Read on to learn more about air sealing, how it’s done, and its many benefits.
What Is Air Sealing And Why Is It Important?
Air sealing your home means identifying points of air leakage into or out of the structure, and then sealing those areas through techniques like caulking or weatherstripping. The exterior of your home – often referred to as the “envelope”or “shell” – is susceptible to both air infiltration (air leaking in from the outside) and air ex-filtration (air leaking out from the inside) through entry points like windows, doors, wood framing, along baseboards, switches mounted on exterior walls, chimneys, fireplaces, attics, and more, according to RESNET.
Air sealing is a critical part of your household’s energy conservation efforts, as air that leaks through your home envelope wastes energy and likely increases your utility costs. The process of air sealing also helps improve indoor air quality as well as the level of comfort within your home. Finally, air sealing is necessary to ensure your home’s insulation works properly and to its fullest potential.
Common Problems Associated with Air Leaks
Have you noticed a room that is particularly drafty, or that your upstairs rooms are consistently colder than downstairs during the winter? Perhaps you feel like the air inside is nearly as muggy as outside during the summer. Or, there are rooms in your home that are 10 to 15 degrees warmer than others during the summer, despite the fact that that air conditioner has been running nonstop. These issues are likely manifestations of air leakage, according to home energy improvement company Green Homes America.
Air leaks can be very serious. In fact, the experts at Green Building Advisor warn that air leakage can negatively impact the longevity of your home’s structure:
“Next to rain, air leaks through walls, roofs and floors can have the biggest effect on the durability of a house. Uncontrolled air flow through the shell can not only carry moisture into framing cavities, causing mold and rot, it can account for a huge portion of a home’s energy use and cause indoor air quality problems to boot.”
Air leaks can also hinder your home’s energy efficiency. During the winter, that means the warm air heating your home is escaping outside; and vice versa in the summer. It also means cold or warm and humid air is entering the home, depending on the season. Your heating and cooling systems must work harder to combat the effects of air leaks, resulting in higher utility bills.
And, because air from the outdoors usually contains water vapor, air leaks can cause mold and condensation buildup inside the home, making for poor air quality that could lead to health issues.
Other problems associated with air leakage include:
- Increased chance for ice dams on roofs in snowy climates;
- More pollen, dust, and insects entering the home;
- Increased noise from outside;
- Less control over humidity levels indoors.
How to Find Air Leaks in the Home
Now that it is understood just how important air sealing is to preserve the durability of your home and improve indoor air quality, comfort levels, and energy efficiency, learn how to find the air leaks that require sealing.
Conducting a home energy audit is the most comprehensive way to find air leaks in the home. A certified professional will evaluate your home’s energy features to identify where your home is losing energy and money, including air leaks or areas with insufficient insulation.
During a home energy audit, a tech may run a blower door test to pinpoint leaks that require air sealing. Blower door tests depressurize the home through the use of a powerful fan that pulls air out of the house, lowering the air pressure inside and reveal the location of many leaks as the higher outdoor air pressures pushes air through unsealed gaps and openings.
This illustration by EnergyStar shows common sources of air leaks inside and outside the home. (Source)
Homeowners can also conduct a visual inspection of the home to find obvious air leaks. The U.S. Office of Energy Efficiency and Renewable Energy suggests inspecting all areas where two different building materials meet, such as:
- Exterior corners
- Outdoor water faucets
- Where siding and chimneys meet
- Where foundation and the the bottom of exterior brick or siding meet.
As for an indoor assessment, the U.S. Office of Energy Efficiency and Renewable Energy advises looking at the following areas where gaps or cracks are common:
- Cable TV and phone lines
- Switch plates
- Electrical outlets
- Where dryer vents pass through walls
- Attic hatches
- Weather stripping around doors
- Electrical and gas service entrances
- Vents and fans
- Doors and window frames
- Fireplace dampers
- Wall- or window-mounted air conditioners.
Air Sealing Techniques
Once sources of air leaks have been determined, it’s time to begin air sealing. Two effective air sealing techniques are caulking and weatherstripping. The U.S. Office of Energy Efficiency and Renewable Energy writes that both methods offer quick returns on investment, often one year or less.
Caulk seals cracks and gaps between stationary components of your home, like around window or door frames. Depending on where the caulk will be applied, you will need to choose from different caulking compounds like silicone, foam, or latex. Before caulking, be sure to address ventilation needs to ensure adequate indoor air quality.
Weatherstripping, on the other hand, is used to seal parts that move, like doors or operable windows. Again, it is important to assess ventilation needs to ensure you maintain adequate indoor air quality before proceeding with weatherstripping. You will need to choose a type of weatherstripping that will withstand wear and tear, temperature changes, weather patterns, and friction; the type of weatherstripping you need may vary from location to location around the home.
Caulking and weatherstripping can be do-it-yourself home improvement projects, but never hesitate to call on a professional to get the job done quickly and reliably.
Air Sealing, Ventilation and Insulation
The U.S. Office of Energy Efficiency and Renewable Energy succinctly sums up a successful air sealing strategy: Reduce air leakage as much as possible, and provide controlled ventilation as needed. Ventilation is crucial to ensure that harmful contaminants like formaldehyde and radon don’t get trapped inside the house once it is sealed. Ventilation also helps with moisture control. Methods of ventilation include natural ventilation (opening doors and windows to let air in). Additionally, spot ventilation (i.e. localized exhaust fans, such as those in bathrooms or above kitchen ranges). Finally, whole house ventilation involves fans and duct systems to exhaust stale air and circulate fresh air throughout the home.
Air sealing goes hand in hand with insulation because the latter won’t work property if large amounts of air escapes or infiltrates the home. For example, the attic particularly posses risky areas. Once air sealing is done and the proper insulation installed, your home’s energy efficiency will certainly improve – perhaps even to the point replacing large furnaces and air conditioning systems with smaller units, saving even more money in the long run.
If you suspect your home is in need of air sealing, give A.Johnson a call. We help homeowners in the Capital District improve the comfort of their homes and reduce utility costs by identifying air leaks, conducting air sealing, and installing sufficient insulation if necessary. Contact us to schedule a home energy audit today!