Window sealants can play a major role in holding heat indoors in winter and keeping heat outdoors in summer. According to the Department of Energy, fully 25% of heat loss in a home is due to air leaks around windows and doors. Most window air leakage occurs due to small gaps in individual window panes, as well as around the main frame around the window. Over time, common putty and other materials frequently used in the original construction of a house dries out and shrinks, allowing air infiltration into the structure.
Newer window sealants have improved measurably over the years. Basic types of window sealants include:
Silicone caulk. This is the standard today, and the best types of this variety are 100% silicone, with no other additives. Silicone caulk resists mold and mildew and is very dimensionally stable over the years, meaning it does not shrink like putty or other materials. It not only stops air leaks, it prevents water damage.
Polyurethane caulk. Polyurethane is similar to silicone but usually only applied to exterior surfaces of the window frame (not indoors). The sealing properties of polyurethane are also similar. However, unlike silicone, polyurethane caulk can be painted.
Acrylic latex caulk. This is a water-based caulk and not appropriately durable against the effects of exterior weather. However, it’s suitable for many interior applications, including the indoor side of window frames. Acrylic can be painted any color and, once it has dried, it can be cleaned with water.
Polyurethane foam. Provided in a can, this expanding foam can be injected into gaps and small voids around the main frame of the window to prevent intrusion of outdoor air and moisture, as well as to reduce energy loss from the interior of the home. Foam air seals better than other insulating materials and is a permanent substance that does not deteriorate. After the foam dries, it can be trimmed, sanded, or painted.
For more about the varieties of window sealants to help reduce heat and cooling loss in your home, contact the professionals at Air Assurance.