Whole House Fans Work Best at Lower Humidity
It’s best to operate a whole-house fan when the outside temperatures are below 72 degrees and the humidity level is less than 75 percent.
Whole house fans were popular in the 1950s, before central air conditioning was common. To operate the fans, you must open windows, as the fans pull in fresh air from outside and pushes out the hot, stale air through the attic vents. Generally, homeowners will turn the whole house fan on at night, when outside temperatures are cooler, and close windows and turn the system off during the day.
Whole house fans use a fraction of the energy compared to traditional air conditioning units. In climates where summers can be hot and humid, some people use them in spring and fall to save on cooling costs. In other climates, a whole-house fan may handle all or most home-cooling needs.
Whole House Fans Differ From Attic Fans
The new ducted style whole house fans are significantly quieter than older models, and cost between $800 and $1,500 depending on how much air it must move. Installation costs range from $600 to $800. Note that a whole-house fan is different than an attic fan.
A handy homeowner may be able to install a whole house fan, as could a handyman service or electrician. Fan installation requires the installer to cut a ceiling hole in a central location. The fan attaches to ceiling joists from the attic. An electrician needs to pull power to the fan and, most often, wire in a wall switch, though some fans come with remote controls or Wi-Fi-enabled controls.