Attic Closed Cell Foam Under Blown Insulation

Properly applied by a professional spray foam should emit relatively low fumes that will altogether dissipate in about a week.

Attic closed cell foam under blown insulation.

Spray foam insulation is an incomplete name. It really should be called spray foam insulation and air barrier. Nothing unusual about that. 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.

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. Because it requires professional installation closed cell foam insulation is pricey but it offers r 6 thermal value for every inch of thickness. 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. 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. They sport insulation values of approximately r 6 5 and r 3 6 per inch respectively. The foam usually polyurethane is sprayed to fill cracks and gaps in the attic to form a hermetically sealed barrier. When we seal the attic with spray foam it s as tight as a butter tub.

However in a traditionally insulated attic insulation on the ceiling the attic is vented. 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. Once you deal with the air up there this problem goes away with or without the insulation in the attic floor. Whereas blown in insulation works by filling the.

A properly done spray foam job not only insulates but also greatly reduces the air leakage of. To get a better air seal. Open cell foams use water as a blowing agent. Spray foam attic insulation spray foam offers the best attic insulation performance available.

Earlier this year i got a question about a home that had spray foam insulation in 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.