Do Attics Require Ventilation With Spray Foam Insulation

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

Do attics require ventilation with spray foam insulation. Yes using spray foam we have added your attic to the conditioned space. This spray foam is applied as a low or high pressure two component polyurethane spray foam that can be applied onto walls in unvented attics to ducts and ceilings and in vented attics and crawl spaces. Earlier this year i got a question about a home that had spray foam insulation in the attic. Spray foam provides an air seal.

Here s the answer to the question posed in my article title. Attic ceiling to stop airborne moisture from reaching a cold surface and condensing inside the building envelope. However in a traditionally insulated attic insulation on the ceiling the attic is vented. It is also known to act as an air barrier however unfortunately it will not protect against vapor and moisture intrusions.

The main aim of ventilating the attic space is to allow the air in the home to circulate. Therefore providing mechanical fresh air ventilation is especially important in spray foam houses. It s terrific because it s pretty much the same temperature as the rest of the house all the time. We also recommend to do no harm when we.

When we seal the attic with spray foam it s as tight as a butter tub. Unvented attics rely on an air impermeable insulation installed to the roof deck s underside i e. Mechanical ventilation systems allow a constant flow of outside air into the home and can also provide filtration dehumidification and conditioning of the incoming outside air. They know roofing materials underlayments flashing and attic ventilation.

Nothing unusual about that. Spray foam insulation may prevent your home from getting enough ventilation. A well sealed home does a better job keeping conditioned air inside. Tell them the attic is to have no ventilation of any type.

Generally speaking that s a good thing. A lot of builders and homeowners are going with spray foam insulation because of the airtightness benefits. The basics ventilation is required but not all ventilation options are appropriate for the home or homes with spray foam insulation.