The main purpose of an attic-fan is to move the hot air out of your attic and keep your whole house cooler. If you’ve ever attempted to go into your attic on a hot day, you know the feeling of the oppressive wall of heat you hit. Well, of course the attic is hot, hot air rises and being the attic is the highest point in the house, the hot air rises into your attic. The air becomes trapped in the space because many attics have limited or inadequate ventilation and the hot air has no place to go. Many homeowners use central air conditioners, window units or fans to cool the house. When the attic is blazing hot, air conditioners and fans have to work much harder to cool the home. The harder the air conditioner has to work, the higher your electric bills will rise.
attic-fans are available in a variety of types including electrically powered and solar powered. To decrease your electrical bills the most, consider a solar powered fan because it costs nothing to run. Typically solar powered fans are slightly more expensive than electrical attic-fans, but the cost difference will be made up on the reduced cooling costs within the first year. As solar power technology progresses, the cost of solar attic-fans drops.
Choosing an attic-fan
The most important consideration when choosing an attic-fan is choosing between electric and solar. There should be very little mind wrestling with this question – solar power will pay off more than electric power. If you choose an electrically powered fan, you will still experience significantly reduced cooling bills.
The second most important consideration is the size of the fan. Measure your house and determine the square footage of the entire house. To get a rough, slightly over estimated square footage, measure the front of the house from corner to corner and not the measurements. Measure the side of the house from corner to corner and note the measurements. Multiple the front measurement by the side measurement. The total will give you the square footage. If your house is two stories, multiple the square footage by 2 to get the total square footage. If you house is three floors, multiply the square footage by 3 to get the total square footage. The attic-fan has to be large enough to accommodate the size of the house or will not be as effective as it could be.
When you go to buy the attic-fan, bring the total square footage information with you and purchase a solar powered attic-fan or electric powered attic-fan that can remove the hot air from the attic efficiently.
Another factor to consider when purchasing an attic-fan is whether you want the fan to automatically switch on when the air reaches a predetermined temperature. attic-fans that automatically turn on are a time saver and a convenience. You won’t have to worry about remembering to turn the fan on or off along with worrying if you actually did turn it on or off.
Where to Position the attic-fan
It may seem as if any open spot in the attic will do – not true. Install the attic-fan in the peak of the roof. If you are unable to situate the attic-fan on the peak, position it as close to the peak as possible. An attic-fan in the peak of the roof is the most efficient spot because the peak is the highest point of the house and the fan will be able to pull out more hot air than if the fan was located anywhere else in the attic. The attic-fan will also send cool air down. If the attic-fan is installed right at the peak the cool air falling will not encounter and mix with the hot air.
When to Use Your attic-fan
As soon as the temperatures rise, switch on your attic-fan during the daylight hours. Put the fan on before the hottest part of the day starts. Leave the fan on until the sun goes down. Definitely run the attic-fan during the day while your air conditioners are running. The attic-fan is capable of lower the temperature in the attic by 40 to 50 degrees Fahrenheit, which will in turn lower your cooling costs by 20 to 30 percent. Using an attic-fan also helps to extend the life of your air conditioners by putting less strain on the unit.
Other Benefits of an attic-fan
Saving money usually tops the lists of benefits for many homeowners, but there are other benefits for installing attic-fans.
attic-fans help to remove excess moisture in the attic. This is especially true if you live in an area that experiences high humidity with the heat. Excess humidity in the attic can lead to mildew and mold growth all over the attic. The moisture and humidity can also create a perfect environment for wood rot. Keeping the attic dry helps to keep your home healthy and structural safe.
Cooling an attic also helps to extend the life of the roof. High temperatures hitting the attic from both the outside and underside can promote roof delamination. Delaminating is the process by which the tiny pebbles on an asphalt roof come off and no longer offer the house necessary protection from wind, rain and snow.
Although attic-fans are considered something you use during hot weather, they are very useful during cold moths too. When outdoor temperatures are cold, indoor attic temperatures are warm. The point at which the warm air and cold air meet develops moisture which usually is at the peak on the joists. The moisture during cold weather can cause mold, mildew and wood rot. Switching the attic-fan on for a few hours a day can help to eliminate the problem. Do not close of attic ventilation during the cold months in hopes of somehow sealing the house from the cold air. Sealing the house creates moisture.