Spray foam is a liquid polyurethane foam insulation product. It is sprayed on like paint, and then expands to about one hundred times its initial size to form an airtight barrier. Spray foam has many applications. It can be used as an insulator, to fill in gaps, or to help soundproof a room. Roofers and HVAC workers may also utilize spray foam.
When used for insulation, spray foam is applied to the spaces between the framing studs in the walls and attic. It will expand up to one hundred times, to accommodate the shape of the crevices. As the house shifts, the foam insulation will too. This will allow the foam to retain its airtight seal, preventing warm air from escaping the house, and cold air from coming in.
Polyurethane foam also works great for use in roofing as it is lightweight and can adhere to clay and concrete tiles, metal, wood, concrete, and standard roofing shingles. It has many uses in roofing including filling in unlevel areas, adding slopes to fix drainage problems, and filling in gaps between the roof and other penetrating items such as chimneys. Perhaps the best feature polyurethane foam has to offer, as far as roofing is concerned, is that it can protect the existing roof from severe weather elements such as hurricanes and hail. A spray foam roof system can last thirty or more years, provided it is properly maintained.
Another benefit to spray foam is its soundproofing capabilities. Noises that can usually enter the room through cracks, crevices and thin sheet rock can be muffled to barely audible levels with the use of polyurethane foam. It can be applied to new homes during the initial building phase, or to older homes as an enhancement. The average homeowner can soundproof his home relatively easily by drilling inconspicuous holes in the drywall between the studs and spraying the foam into the space. A small patch job will be necessary to repair the holes.
A popular use for spray foam is in the HVAC industry. When sprayed into the walls, ceilings and floors where HVAC ducts penetrate, the foam provides resistance against movement and moisture. It also helps maintain the integrity of the building. When sprayed directly onto the duct work, it regulates temperature, prevents condensation and reduces vibration.
From a health and environmental perspective, spray foam is rather beneficial. It does not contain formaldehyde, hydrochlorofluorocarbons, hydrofluorocarbons, or any other hazardous chemicals. By providing a tight seal in buildings, it helps prevent dust, pollen and other allergens from entering. Finally, it lessens the likelihood of developing condensation in dwellings, preventing the growth of toxic molds and mildew.