Can a Whole-House Fan Keep Your Whole Family Cool?
A whole-house fan can be a valuable ally in the quest for a cool, comfortable house and manageable energy bills—but is one right for you?
Summer tests your ability to keep your cool—both literally as you cope with the heat and figuratively as you fume over the spike in your energy bills. With energy costs rising, running an AC unit around the clock can be a pricey proposition. This makes some folks wonder whether installing an energy-efficient whole-house fan could help keep their homes cool and their utility bills reasonable.
Homeowners looking at this alternative to central air may be on the right track. Whole-house fans are a great option in many situations, but not all. Daniel O’Brian, a technical expert for online retailer SupplyHouse.com, explains the benefits and limitations of whole-house fans and suggests some factors homeowners should consider.
A whole-house fan expels warm indoor air and simultaneously pulls in fresh outdoor air.
Air conditioners work with the indoor air, drawing in warm air, chilling and dehumidifying it over refrigerant coils, and then returning the newly cool, dry air to the home. By contrast, whole-house fans exchange air with the outdoors. O’Brian explains, “They remove hot air from the home when outdoor temperatures are cooler than those inside,” typically in the morning or evening, and draw in cooler outdoor air. A whole-house fan, such as the Infinity 1100 Whole-House Fan by Tamarack (available from SupplyHouse), is typically installed in the ceiling of the uppermost floor of your home, which is where heat tends to collect. When you turn on the fan and open windows on the lowest floor of the house, the fan pushes hot air out and draws in outdoor air through the windows.
Naturally, how well a whole-house fan cools off the home depends not only on choosing the right model of fan but also on external factors like temperature and humidity.
Switching to a whole-house fan works best in cool, dry locales.
Low humidity levels are an important factor in comfort. Most people will feel comfortable at a temperature between 73 and 78 degrees Fahrenheit as long as the humidity level is less than 50 percent. When the humidity level reaches 60 percent or higher, though, things start to feel sticky.
Because whole-house fans draw fresh outdoor air into the home but do not dehumidify it, they work best in climates where outdoor humidity levels are already relatively low. “This generally corresponds to desert areas and regions away from the coasts,” O’Brian notes. A whole-house fan isn’t advisable in Pensacola, Florida, where there’s an average humidity of 72.5 percent, but one could do some good in such places as Phoenix (with an average humidity level of 36.6 percent) or Las Vegas (30.3 percent). In an appropriately dry location, a whole-house fan like the high-efficiency HV5800M Cyclone Whole-House Fan by Tamarack (available from SupplyHouse) can quickly replace uncomfortably warm indoor air with refreshingly cool air once the outdoor temperature dips below 73 degrees Fahrenheit or so.
A good rule of thumb: In any region where the average humidity is 50 percent or less, a whole-house fan may be a good option. If your hometown is stickier than that during the summer, you’d be better served by a traditional air conditioner that’s equipped to reduce the humidity level.
Note that if you live in a region where winters can be very cold, such as Denver, “the openings for the fan in the ceiling can risk becoming a spot for heat loss,” O’Brian says. This doesn’t necessarily mean that you have to completely avoid a whole-house fan. You just need to choose carefully. Some units—for instance, the HV1000 R-38 Insulated Whole House Fan by Tamarack (available from SupplyHouse)—have insulated doors to prevent heat from escaping.
Running these fans can cool your house for a fraction of what it takes to power an AC unit.
Perhaps the biggest benefit of a whole-house fan is its energy-efficient operation. The process used by a traditional air conditioner to cool a house is expensive—depending on where you live, cooling can account for as much as 27 percent of your total electric bill, according to the U.S. Energy Information Administration. That can easily translate into hundreds of dollars added to your electric bill. A whole-house fan, on the other hand, uses approximately 10 percent of the amount of energy it takes to power a traditional AC unit.
That doesn’t mean you have to have just one or the other. If you live in a low-humidity area, you may want to run your AC as needed at the hottest time of day, usually mid to late afternoon. Then, once the outdoor temps drop, you can open your windows and switch to the fan so you can keep cool overnight for a fraction of the cost.
Whole-house fans today are much quieter than their predecessors.
The early whole-house fans of the 1970s and ’80s could be rather noisy, with some creating such a racket that residents in the home couldn’t hear one another speak over the din. But times have changed, and technological advancements have improved whole-house fans just as they have led to better HVAC units. “Many of today’s whole-house fans offer remarkably quiet operation,” O’Brian says.
If peace is a priority, check out the HV5500G Blizzard Whole-House Fan (available from SupplyHouse). It’s one of the quietest whole-house fans on the market today, coming in at just 56 decibels, which is similar to the sound made by light traffic on the street in front of your home.
It’s best to leave installation to the professionals.
If it looks like a whole-house fan could be the money-saving solution you’re looking for, great! But don’t jump the gun with a DIY installation. Before attempting it on your own, first check with local code to make sure you won’t be violating any rules, and know your limits. “The option for DIY installation depends on the skill level of the installer,” O’Brian says. For example, the CQ1100 Ducted Whole-House Fan Kit by Tamarack (available from SupplyHouse) may require installing a dedicated exterior attic vent in order to effectively remove the hot air from the attic. Depending on the configuration of the attic, this could involve installing a new vent directly in a sidewall of the attic or through the roof, both of which are tasks best reserved for the pros.
This content is paid advertising created in partnership with SupplyHouse. Its facts and opinions are those of BobVila.com.