Spray Insulation Attic Ventilation

Nope you absolutely do not need to ventilate a spray foam house and here s why.

Spray insulation attic ventilation.

One of the biggest benefits of using spray foam is to get greater airtightness. 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. Actually you should probably get rid of power attic ventilators whether or not you re sealing the attic but that s another article. That means you get rid of all attic ventilation whether it s passive ridge gable soffit vents or active fans.

However in a traditionally insulated attic insulation on the ceiling the attic is vented. Spray foam from home logic is an excellent insulation type to choose for the attic. Traditional methods of insulation materials and design call for using air circulation within the attic space to assist in drying excess moisture. Spray foam is applied directly where it s needed ensuring that any ventilation vents are left untouched.

Earlier this year i got a question about a home that had spray foam insulation in the attic. The spray foam expands on contact filling up the space where it begins working immediately. Insulation is used in an attic for cross ventilation to minimize potential for moisture accumulation and condensation to help energy savings and moisture control. 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.

Spray polyurethane foam will provide thermal insulation that will minimize air infiltration which can help to save on heating and cooling costs within the indoor environment. Open cell spray polyurethane foam or closed cell spray polyurethane foam ccspf insulation can be sprayed along the underside of the roof sheathing to provide a conditioned and insulated attic space that can be durable and efficient in all climate zones see figure 1. When we seal the attic with spray foam it s as tight as a butter tub. In heating and cooling climates this moisture could potentially travel through fibre insulation in building cavities.

It s terrific because it s pretty much the same temperature as the rest of the house all the time. I have a spray foamed attic. Nothing unusual about that. Compared to traditional insulation whether fiberglass or cellulose spray foam has the potential to provide better performance via its air sealing properties high r values per inch of thickness and in the case of closed cell spray foam ability to repel moisture.