Air sealing is a critical first step before adding insulation, such as fiberglass, blown foam or cellulose. It reduces drafts and improves comfort while lowering energy bills.
It also keeps hot and humid outside during summer and cold, dry air inside in winter and blocks moisture vapor that can lead to mold and mildew. Caulking and weather stripping are simple, cost-effective air-sealing techniques that offer quick returns on investment.
Air Leaks
Air leaks around windows, doors, vents, chimneys, and plumbing penetrations allow outside air to enter the home. This air can carry pollen, allergens, and moisture that ruins insulation. Sealing these leaks with caulk, weather stripping, and expanding foam is a good way to make the home more comfortable, reduce energy costs, and increase its value.
Air sealing is often the first step of an energy assessment, before adding insulation like blown-foam or fiberglass. It is typically done by a Residential Registered Vendor using a blower door and other diagnostic equipment, including a thermal camera.
Some signs that your house is leaking air are an increased utility bill, a musty or musty smell, and drafty rooms. Ideally, you should have your whole house analyzed by a professional and have it insulated with both air and insulating barriers.
Air sealing can be expensive but many homeowners recoup the investment within three years due to reduced heating and cooling costs. In addition, you’ll enjoy the health benefits of a healthier indoor environment.
Moisture
Air sealing is a critical step before installing insulation and addresses leaks in stationary house components like windows, doors, vents and fireplace flues. It also seals cracks and crevices where air can escape or enter a house and is typically used along with weather stripping to eliminate gaps that can allow cold outside air into a home or warm indoor air out during the summer.
It also helps keep moisture, allergens and pests from entering a home and can lead to healthier indoor air quality. It reduces energy costs by minimizing the strain on heating and cooling systems. It can even help to prevent the accumulation of moisture in the walls, which can create mold and mildew.
Insulation and air sealing are the yin and yang of a home’s energy efficiency and comfort. They work together as a team and should be installed in conjunction with an energy audit to determine the best course of action for your house. An insulation contractor will use a blower door or smoke pencil to locate and measure the amount of leakage in your home’s walls and ceilings. If necessary, the consultant will recommend additional upgrades including air sealing. Air sealing keeps conditioned air inside and the cold and hot outdoor air out, saving energy bills, improving comfort and creating a healthier indoor environment.
Condensation
Air sealing is an important part of home insulation because it reduces drafty spaces that rob your house of energy. It also minimizes the strain on your heating and cooling system, prolonging its lifespan and keeping you more comfortable. Additionally, it helps keep outside pollutants, dust and moisture out of your living space.
It is possible to do a basic air seal by yourself but it is best done with the help of an experienced contractor who can use a depressurization fan (sometimes called a blower door) along with smoke pencils and an infrared scanner. A professional can also use specialized caulking and spray foams that are designed to fill gaps, crevices and holes.
When warmer, moist air comes into contact with a cold surface such as a wall or ceiling it forms condensation that can cause mold and mildew problems. This is why it is necessary to properly air seal the attic and other hard to reach areas of your house to minimize the movement of warm, moist air into colder places.
The benefits of air sealing are many and varied. It can drastically cut your energy costs, make you more comfortable, and improve the indoor quality of your house. It can even recoup its investment within three years and is a good complement to proper insulation.
Insulation
The goal of air sealing is to reduce the movement of air in and out of your home. This can be accomplished by caulking, weather stripping and spray foam. This is often best done before adding insulation. A well-air sealed home, paired with proper insulation is the best one-two punch for lowering energy bills, improving comfort and creating a healthier indoor environment.
In homes where a lot of energy is being wasted, the first step in addressing the problem is to air seal. This can be done by a residential Registered Vendor who will use diagnostic equipment such as a blower door to assess the relative leakiness of the building envelope and recommend air-sealing products. Typical areas where leaks are found include doors, windows and basements. In addition to reducing the energy waste, air-sealing also prevents moisture, mold and pests from entering the house.
Insulation is like a down lining in a winter coat, helping keep warm air in and cold air out. Air sealing, on the other hand, is like the wind-breaker layer of the coat – stopping excess air flow in and out, which saves energy and creates a warmer, more comfortable home.
Ideally, both air sealing and insulation are installed as part of a whole-house retrofit. While it’s possible to insulate and air seal a existing home, it’s much easier and more cost-effective to do both at the time of construction.