Foam Insulation to Spray in the Attic

Identification

• Sprayed-foam insulation is often made from polyurethane, which can also be installed in foam boards. According to the United States Department of Energy, sprayed-foam insulation is less expensive than foam boards. Sprayed-foam insulation molds itself to attic surfaces and helps reduce heating and cooling costs. Polyurethane foams use non-chlorofluorocarbon gases to deliver the foam, which is recommended to protect the ozone.

Types

• While polyurethane is a primary ingredient in sprayed-foam insulation, there are other types of insulation that can be sprayed or foamed in. These products are made from phenolic, cementitious or polyisocyanurate. Icynene foam is a less commonly used foam insulation, but is extremely versatile because it can be sprayed or injected into the attic. Tripolymer foam is a sprayed-foam insulation that is water soluble, fire resistant and provides excellent air sealing.

Installation

• Foam insulation is available in small spray containers or larger pressurized sprayers. After foam insulation is installed, it expands into attic spaces and hardens. Most spray foams require special equipment, so the United States Department of Energy recommends installation by a professional contractor. Homeowners who wish to spray insulation in themselves should obtain instructions on installation for best results. Equipment used to spray insulation is available at equipment rental stores. All sprayed-foam insulation must have a thermal barrier, such as drywall, covering the foam. In certain states, building codes require a vapor barrier or air barrier after insulation installation.

Considerations

• Sprayed-foam insulation is more expensive than other insulation, such as blanket insulation, but does provide an air barrier which will reduce weatherizing costs over time. This type of insulation is easiest to install during the construction of the home, but can be used in existing homes as well. When hiring a professional insulation installer, always get at least three estimates as prices can vary greatly.