Insulation (with air sealing and optional
Attic/ceiling insulation prevents conductive heat transfer between your home, the attic space and the outside. Like all insulation, ceiling insulation helps keep the home warm in the winter and cool in the summer. Attic insulation is often the easiest and most cost-effective place to insulate because most attics provide easy access for the installations. The ready access and lower insulation cost often makes this a very cost-effective measure. This is not to say ceiling insulation is necessarily more important than wall or floor insulation. Attic insulation is most effective when the ceiling plane between the home and the attic space is tightly sealed, so air sealing should be performed before attic insulation is installed.
Wall insulation reduces heat transfer through your home’s walls. Wall insulation is as important as attic insulation but often more difficult to install. Most wall insulation is placed in the wall cavity between the framing studs, although rigid board insulation is sometimes used for continuous insulation. The most practical method to insulate existing enclosed walls is by blowing in cellulose fiber. This not only provides a thermal barrier, it also air seals the walls of your home, preventing excessive air infiltration. If insulation already exists in the wall cavities, it can be very difficult to blow in additional insulation. If there is no existing insulation, cellulose can be blown into the walls through holes drilled from inside or outside. The holes are then plugged and finished to match the wall.
Ducts are used to distribute conditioned air throughout houses that use forced-air heating and cooling systems. In a typical house, however, about 20 percent of the air that moves through the duct system is lost due to leaks and poorly sealed connections. The result is higher utility bills and difficulty keeping the house comfortable, no matter how the thermostat is set. Because some ducts are concealed in walls and between floors, repairing them can be difficult. However, exposed ducts in attics, basements, crawlspaces, and garages can be repaired by sealing the leaks with duct sealant (also called duct mastic). In addition, insulating ducts that run through spaces that get hot in summer or cold in winter (like attics, garages, or crawlspaces) can save significant energy.
Air Sealing is the treatment of small cracks and gaps in a home that allow outside air to infiltrate inside. This infiltration can result in as much as 20% or more of the typical home’s heating and cooling costs. In the winter, cold dry air leaks into the home while the heated air exits. In the summer, the hot outside air enters the home and brings unwanted humidity. Outside air can leak in around window and door frames, floor and ceiling joints, electrical and plumbing access points, wall joints, exhaust fans, etc. While any one of these small leaks may be minor, collectively they can have the same effect as leaving a window open all year long. Air infiltration can also cause water vapor to condense inside walls and ceilings, causing insulation to become wet and ineffective, resulting in the growth of mildew and structural damage. While it is possible to make a home too air tight without proper ventilation, the vast majority of homes are much too drafty. All ActOnEnergy insulation installations are done with blower door assisted air sealing.
Blower door-assisted air sealing is an effective and accurate method to measure air tightness and identify areas where air infiltration is occurring. Using the blower door, a contractor measures overall leakage and identifies specific locations. Those locations are then treated using a variety of methods (caulk, spray foam, weather stripping, etc.). Leakage is measured periodically during the process to ensure that the home is not sealed too tightly. Safety testing of any combustion appliances in your home should be conducted before and after air sealing is done. This is the only method to accurately and safely perform air sealing on a home.