Attic Closed Cell Foam Under Blown Insulation

It really should be called spray foam insulation and air barrier.

Attic closed cell foam under blown insulation.

To get a better air seal. A lot of builders and homeowners are going with spray foam insulation because of the airtightness benefits but then the questioner mentioned that the spray foam contractor had intentionally left big holes to the outside by not sealing the gable vents. Homeowner james polk who recently hired sunlight contractors to install approximately 3000 square feet of spray polyurethane foam in his destrehan home describes his experience which is typical of a job done right. Open and closed cell foam insulation use a blowing agent to forms the cells within it.

They sport insulation values of approximately r 6 5 and r 3 6 per inch respectively. Closed cell foams use enovate also known as 245fa which is. Spray foam provides the highest r value while open cell spray foam has about an r value of 2 2 to 3 5 per inch closed cell spray foam has about 6 7 per inch. Earlier this year i got a question about a home that had spray foam insulation in the attic.

One huge benefit of the spray foam insulated attic is that conditioned air leakage from the ac furnace duct system is contained and used to condition the attic. The evaluation service report esr for spray foam insulation products provides a valuable resource based on a third party review of testing information useful for utilizing these products successfully and according to code requirements. Whereas blown in insulation works by filling the. Nothing unusual about that.

The foam usually polyurethane is sprayed to fill cracks and gaps in the attic to form a hermetically sealed barrier. Because it requires professional installation closed cell foam insulation is pricey but it offers r 6 thermal value for every inch of thickness. Once you deal with the air up there this problem goes away with or without the insulation in the attic floor. Choose from two types.

Both low density open cell and medium density closed cell spray foam can be used in an unvented attic to provide the needed thermal resistance and airtightness. When we seal the attic with spray foam it s as tight as a butter tub. Spray foam attic insulation spray foam offers the best attic insulation performance available. However in a traditionally insulated attic insulation on the ceiling the attic is vented.

Closed cell and open cell aka 2 pound and pound respectively. A properly done spray foam job not only insulates but also greatly reduces the air leakage of.