Spray Foam Attic Vent

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.

Spray foam attic vent.

Heat from the house rises up to the attic but when there isn t one the heat rises up to the roof. If spray foam is used a vent space may still be needed directly under the roof deck. The spray foam expands on contact filling up the space where it begins working immediately. It s terrific because it s pretty much the same temperature as the rest of the house all the time.

This is not an issue specific to spray foam as much as it is a characteristic of peel and stick membranes. 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. Spray foam insulation that s convenient and easy to use. Class i e 84 fire retardant meets building code spec.

Get your kits the easy to use spray foam kit. Rigid foam and spray foam are two of them. Because basically now that attic is a conditioned space. Earlier this year i got a question about a home that had spray foam insulation in the attic.

Spray foam is applied directly where it s needed ensuring that any ventilation vents are left untouched. R value of 7 in 1 inch 97 closed cell foam. Unvented attic assemblies unvented attics rely on an air impermeable insulation installed to the roof deck s underside i e. What you re looking at there is the place where a power attic ventilator had been.

Nope you absolutely do not need to ventilate a spray foam house and here s why. Use closed cell foam it green for attic rafters. I have a spray foamed attic. All insulation materials require proper venting.

Spray polyurethane foam is a chemical product that is created by two materials isocyanate and polyol resin that will react with each other when they are mixed and will expand up to 30 to 60 times its liquid volume as it is sprayed in place. Spray foam from home logic is an excellent insulation type to choose for the attic. Wood has an r value of about one per inch of thickness. Nothing unusual about that.

Cathedral roofs especially need a lot more insulation between the ceiling and the rafters because there usually isn t any attic space. The best attic insulation. Attic ventilation and spray foam don t mix that photo above is from an existing home that had spray foam insulation installed in the attic over the master bedroom.