Across the country, the definition of a whole house fan and an attic fan varies, causing some confusion.
A whole house fan is a type of fan installed in a building's ceiling, designed to pull hot air out of the building. Most whole house fans force the air into the attic space. This causes a positive pressure in the attic, forcing air out through the roof vents, while at the same time producing a negative pressure inside the living areas, which draws cool air in through open windows.
An attic fan, on the other hand, is installed at the roof level (or gable end), and it regulates the heat level of a building's attic by exhausting hot air. An attic fan requires additional roof vents to draw in fresh air as the hot air is exhausted.
A whole house fan is a primary natural cooling device that can significantly enhance, reduce or even eliminate the need for 'manufactured' cool air. Consuming far less energy than air conditioning, a whole house fan can significantly lower the temperature in a building very quickly. Effective whenever outdoor temperatures drop below indoor temperatures, an AirScape Whole House Fan can cool down your home and your electric bills.
A whole house fan:
- mounts between living space and attic
- runs only during cooler evening, night, and morning hours
- draws fresh cool air into your living space through open windows
- pulls stale indoor air into the attic and forces hot attic air out through the roof vents
- cools the living space and draws heat buildup out of entire building structure
Attic fans operate during the heat of the day to reduce attic heat buildup -- and they ventilate the attic space only. Alternatively, but with the same goal of keeping you cool, whole house fans are run in the cool of the evening, night, and morning, drawing cool, fresh air into the home while forcing hot air out through the attic.
An attic fan:
- mounts between attic space and outside
- runs during the heat of the day
- removes super-heated air from your attic actively (typically, this is achieved passively using roof vent convection)
- creates negative pressure in the attic that draws outside air in through roof venting
- helps mitigate heat buildup in the attic structure, keeping the temperature as close to ambient as possible
The addition of an AirScape Whole House Fan delivers energy efficient natural cooling, providing home comfort and peace of mind. We recommend them for all regions across the US, wherever there are warm days and cool nights. As for attic fans - if you live in a hot, dry, sunny climate, consider adding a solar-powered attic fan in addition to a whole house fan. This device is self-powered, easy to install, turns on automatically as appropriate, and will have a significant impact in reducing building heat load. They are not a replacement for a whole house fan, but they are a smart addition to your home cooling strategy in sunny, hot climates. Our AirScape Solar Attic Fans are engineered to complement our AirScape Whole House Fans, and together they can provide your natural cooling solution.