Why Is Air Sealing Important in a House
With the arrival of chilly weather on the horizon, it's once again time to clean the cobwebs from your furnace and prepare for another warm winter inside your home. There are a variety of ways that you can use to make your home more pleasant in the winter, ranging from caulking around window casings to wrapping your windows in plastic, but air sealing is one of the most successful. Ultimately, air sealing has an impact on the building envelope of your home by effectively sealing off all of the exposed gaps, flaws, and imperfections in your home's interior from the elements on the outside. This is normally accomplished by the use of an expanding spray foam that fills and penetrates the gaps in order to prevent air infiltration from occurring. As estimated by the ENERGY STAR program, the average home's construction envelope contains enough of these small holes and cracks to be equivalent to leaving a window open all year round in terms of square footage (so that you can watch your money float away through it).
In a home that is already well-insulated, why would I need to air seal it?
Air sealing and insulation, like Simon and Garfunkel, are most effective when used together; they are the yin to each other's yang. The infiltration of air into a home that has been well insulated but has not been properly (or has been inadequately) air sealed will continue indefinitely. Insulation can assist in slowing the flow of air into and out of your home, but it cannot prevent it from doing so; think of it as a blanket with a hole in the middle. In the opposite situation, a home that is air-sealed but does not have adequate insulation will have a difficult time keeping the air inside the building envelope of your home; think of it as attempting to remain warm by wrapping oneself in cellophane. It is recommended that you use these two systems in conjunction if you want to improve the energy efficiency and reduce your heating and cooling bills. The recommended method for air sealing and blowing in insulation in a place such as an attic, in the best case scenario; however, if this is not possible, the property can still be successfully air sealed after it has been insulated.
When and where should air sealing be performed?
However, there are numerous locations where air leakage can occur, such as around rim joists and sill plate in the basement and around beams and other construction in the attic. Canister lights, for example, are one of the many places where air leakage can occur, and they should be sealed as soon as possible. See how many of these common places can be found in the illustration below.
When it comes to air sealing, how much does it cost?
As far as house modifications go, air sealing is quite affordable, and it is the most cost-effective option to reduce your excessive energy bills. In general, the most difficult air sealing jobs cost roughly $1 per square foot of house, with less complicated projects costing less than that. Of course, each home has its own set of requirements, so prices will vary.
What is the procedure for air sealing?
When it comes to air sealing, the most common method is to use a huge canister filled with polyurethane that expands when it comes into contact with air. It is sprayed from a canister through a long metal hose to reach those difficult-to-reach places like attics and crawl spaces. A filthy job, air sealing is often not a project that is recommended for the do-it-yourselfer because it includes crawling into crawl spaces and searching for cracks and crevasses in the conventional spots as well as any that may be specific to the particular home. Work that is normally best left to a professional weatherization contractor.
Isn't it true that the air leaks in my house provide more circulation and ventilation?
Despite the fact that air sealing your home is a positive thing, it is also necessary to have sufficient air circulation in your home to avoid mold formation and other byproducts of poorly circulated, toxic air in the first place. Effective air circulation, on the other hand, is best achieved by allowing exhaust fans and attic vents to do their jobs, rather than by allowing air leakage to occur. A properly sealed home should also have adequate ventilation to allow for the expulsion of contaminated air and the intake of fresh air.
When it comes to overall effectiveness and price, air sealing is difficult to beat. If you live in a home that isn't quite as comfortable as you would like or if your energy bills seem to be going through the roof for no apparent reason, having your home air sealed is a weatherization project to consider for this winter.