Ordinary fans make you feel cooler by moving air around, but they don’t cool the air. Whole-house fans operate on an entirely different concept. Installed in the attic or on the ceiling between the attic and living space, whole-house fans are designed to pull large volumes of warm, stale air up and out of the house while drawing fresh, cooler air in from outside.
The best way to use a whole-house fan, according to Quiet Cool Manufacturing, which makes Quiet Cool Whole House Fans, is by turning off the air-conditioning in the evening when the outside temperature is below 85°F (29°C), and then turning on the fan.
Whole-house fans cost between $430 and $1,550, according to R.E. Williams Contractor, which distributes fans.
Savings and payback period depend on the house and the climate, says Mary Driscoll, an R.E. Williams representative. "(A fan) definitely saves you money," she says. "Our fans are more energy-efficient than a traditional air-conditioning unit."
Noise can be an issue with whole house fans—especially, as the EPA notes, if they are improperly installed. In general, according to the EPA, a large-capacity fan running at a low speed is quieter than a small fan running at a high speed. The agency recommends installing all fans with rubber or felt gaskets to lessen the noise, and setting multi-speed fans to lower speeds.
R.E. Williams's fans have "noiseable" ratings, Driscoll said.
Of course, whole-house fans are effective only when the outdoor temperature is lower than the indoor temperature. But in climates where the temperature drops at night, a whole-house fan can save 50 to 90 percent of the cost of air-conditioning.