According to studies by the Home Ventilation Institute, home owners my experience as much as 30 percent savings on air-conditioning costs with an attic fan. Commonwealth Edison says air conditioners don’t have to run as often when a house isn’t fighting a hot attic. Any home with an unfinished attic needs an attic fan. An attic fan can: save homeowners up to 30 percent ontheir cooling bills, decrease temperatures in upstairs rooms by up to 10 degrees, lengthen roof life by keeping shingles cooler, add resale value to your home. ~ From the “Naperville Sun”