Spray Foam Insulation Attic Only

It has been said that insulating with spray foam insulation at the roof line will lead to moisture problems with the roof sheathing.

Spray foam insulation attic only.

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. 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. Spray foam attic insulation pros and cons.

Earlier this year i got a question about a home that had spray foam insulation in the attic. Unlike solid insulation products that require careful measurement cutting and fitting spray foam can cover even the most uneven surface instantly. Spray foam insulation is an incomplete name. To get a better air seal.

Attic ceiling to stop airborne moisture from reaching a cold surface and condensing inside the building envelope in this design insulation effectively separates the interior and exterior spaces while slowing down moisture flow so the dewpoint is not achieved within. The best part of using foam it green spray foam on an attic floor is you only need 1 inch cured thickness to seal the living spaces you use from the attic. Only spray polyurethane foam can be used for this application as batt insulation will end up sagging and blown insulation simply can t adhere to the roof decking. Image courtesy of d7 spray foam insulation houston tx using spray foam insulation in an unvented attic application.

A properly done spray foam job not only insulates but also greatly reduces the air leakage of. 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. Whereas too little spray foam insulation can leave for thermal bypass because of the complete lack of insulation in the attic. It really should be called spray foam insulation and air barrier.

When we seal the attic with spray foam it s as tight as a butter tub. Polyurethane or polystyrene spray foams can provide thorough coverage to roof rafters and attic walls in much less time than is needed for other materials. Once you deal with the air up there this problem goes away with or without the insulation in the attic floor. Foam it green kits are portable and disposable and because they are low pressure the re entry time for the room being sprayed is only 1 hour.

This application effectively seals off the attic from the outdoors and eliminates air leakage and infiltration through the attic and roof areas. Spray foam insulation is an air barrier material that creates a seal against air movement. Moisture is also another huge issue when it comes to spray foam insulation in an attic.