Spray foam insulation is an effective way to seal up gaps in your home and save on energy costs. The kits come in various sizes and usually cover 200 to 600 board feet per kit. An open-cell spray foam kit will cover more area, with each can providing approximately 25 board feet of coverage. Open-cell foam is often referred to as half-pound foam, while closed-cell foam is known as two-pound foam.
Recently, some spray foam manufacturers have released products that can be reapplied four hours after the initial application. Exterior roof foam is a closed-cell foam that is usually applied to the outside of flat or low-sloped roofs. Foam insulation with the same R-value as that sprayed can be installed with truck-mounted machines with an aerosol foam kit. It works great for my work van, reducing road noise and temperature significantly.
Tests conducted by Oak Ridge National Laboratories have shown that when they built identical houses, one with R30 fiberglass and the other with R30 spray foam, the spray-foam house was more than 50% more energy efficient than the fiberglass one. The amount of usable foam from a can of spray foam insulation will depend on the conditions of use. Spray foam insulation has the ability to block all three forms of heat transfer, making it an ideal choice for many applications. It is important to note that open-cell spray foam should not be used in areas with high humidity levels.
The price of spray foam insulation is calculated per clapboard foot, a three-dimensional measure of volume, not to be confused with the square foot, which is a two-dimensional measure of area. The spray insulation foam for voids and crevices found in Home Depot is generally used to seal smaller cavities left by other types of insulation. Open-cell foam is better for wood-framed or wood-framed ceilings, as it allows water to enter, making it possible to identify and repair any leaks before they become a problem.
