In use since the 1940s, foam insulation is a two-part liquid insulation material that was originally used in aircraft. In more recent years, foam insulation has become more popular with homeowners and builders. Spray foam insulation protects and air seals by expanding to fill up a form 40 – 100 times its size, depending on the type of foam used. When foam insulation is used in the attic, it creates an air seal, which helps reduce the heating and cooling bills for a home. The two liquid parts, ISO and a resin are kept separate until sprayed through a heated hose to the spray gun upon application. There are two types of foam insulation. Open cell and closed cell.
Closed cell insulation is higher density and more rigid than open cell and although it is used primarily in exterior applications, it can also be used in interior applications as easily as open cell insulation, but it is not as easy to work with as open cell insulation is. When closed cell insulation is used in a pole barn, for instance, the walls are stronger because the closed cell insulation reinforces the wall, making it less likely to be damaged when hit by equipment. Closed cell insulation also rejects bulk water and is recognized as a flood-resistant material by FEMA. Benefits of closed cell insulation are:
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Ability to reject bulk water.
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Can be applied at very low temps.
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Adds to a wall’s racking strength.
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Impact resistant.
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Higher R-value per inch – easier to accommodate high R-value requirements in narrow spaces.
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Lower vapor permeance – can be a Class II VDR.
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High tensile and bond strength.