Whole-House Fan Cools Inside for Whole Lot Less

Before air-conditioning was all the rage, Southern California had the sleeping porch. Cool outside air offered a natural respite from stifling interiors.

Thanks to the whole-house fan, modern-day residents in mild or coastal climates still can take advantage of Mother Nature without camping out.

The powerful fan draws cool outside air inside through open windows and pulls hot room air up to the attic and out roof or gable vents. It takes just minutes to cool an entire house and costs 80% less to operate than air-conditioning, according to Cory Thomas, owner of Superior Attic Fans in San Clemente.

Usually located in a central hallway or a stairway in a two-story house, a whole-house fan can be turned on as soon as the outside temperature drops three degrees below the indoor temperature.

The fan can be used to reduce or even eliminate the need for air-conditioning (the biggest energy user in your home). Generally, a whole-house fan will cut seasonal air-conditioning bills by 50%, said Rich Brown of Lawrence Berkeley National Laboratory’s energy analysis department.

But the fan can only cool a house to the outside temperature and usually only works in the evening.

Unlike an air-conditioner, it does not dehumidify and can bring dust and pollen inside along with fresh air. Good attic ventilation is a must and a loose installation can cause vibrations and excessive noise. An insulated fan cover, installed from within the attic, should be used when the fan is not operating.

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A whole-house fan for a 1,500-square-foot house would cost about $600 installed, said Jeff Berkowitz of Berk’s Electrical in Orange. He uses one in his home and said demand for the fans is on the rise.

Do-it-yourselfers should check the U.S. Department of Energy’s Web site, https://www.eren.doe.gov/buildings/home _fan.html, for estimated costs and installation procedures as well as for advice on using a whole-house fan.

--LYNN O’DELL

* Send your questions or suggestions regarding energy use to Home Design, Los Angeles Times, Orange County edition, 1375 Sunflower Ave., Costa Mesa, CA 92626, or send e-mail to ocsocalliv

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