Do Attics With Spray Foam Insulation Need Ventilation

By amanda wooley mar 23 2020 indoor air quality odor removal vocs did you know that the united states federal housing authority recommends that every home has a minimum of at least 1 square foot of attic ventilation for every 300 square feet of attic floor space.

Do attics with spray foam insulation need ventilation.

They need the right level of ventilation but they also require insulation in order to help improve the energy efficiency of the property. As such he does not plan to install a ridge vent whirly birds soffit vents or gable vents. Here s the answer to the question posed in my article title. We also recommend to do no harm when we.

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. In many they don t get that far. Whether you re building a new home or retrofitting an existing home though you ve got to remember that the hip bone s connected to the thigh bone. Yes using spray foam we have added your attic to the conditioned space.

When we seal the attic with spray foam it s as tight as a butter tub. It will have pine siding metal roof and double paned windows. Or as we say in building science a house is a system. Do you need attic ventilation with spray foam insulation.

It s terrific because it s pretty much the same temperature as the rest of the house all the time. It s nice that the spray foam insulation contractor recognized the need for combustion air in that case. However the opposite is true when the attic floor is air sealed and insulated. My framing contractor recommends use of foam spray insulation instead of fiberglass insulation.

Therefore providing mechanical fresh air ventilation is especially important in spray foam houses. Even when outside air is hot and humid if the attic space is air sealed from the interior it is much hotter than outside air. As such it would seem venting the attic would increase the potential for condensation. However in a traditionally insulated attic insulation on the ceiling the attic is vented.

Do attics with spray foam insulation need ventilation. Nope you absolutely do not need to ventilate a spray foam house and here s why. I am building a 2 500 sf house installed on wooden piers 2 ft off the groung.