Attic fans draw super-heated atmosphere from attic spaces and vent it to the outside. While attic fans do not have an immediate affect on the heat inside living spaces, they do help alleviate some strain on air-conditioning systems. These fans function automatically through the heat of the day, supplying active air movement inside the attic once the home needs it most. Installation involves cutting holes in the home, putting electric connections, and doing some heavy lifting.
Choose which kind of fan you want for your home. Attic fans mount on the roof or in one of the gables. The principles of the way they function are the same. Both units draw cooler air from outside the attic — via soffit or other attic vents — and expel it into the outside through the fan opening. This creates air movement inside the attic space.
Roof-mounted attic fans require the elimination of roof sheathing and shingles by cutting them using a power saw. Gable-mounted fans typically need minor expansion of the existing opening in case a gable vent is currently set up. If no vent exists, you must cut siding and wall sheathing to produce the essential opening.
Mounting the Fan
Roof-mounted fans come with a base made from plastic or sheet metal. The base sits on top of this roof and functions like both a mounting plate and roof flashing. Once the fan is set up, you can cover the base with roofing stuff as you would with any flashing. Gable-mounted fans need a good base, typically made from plywood, using a cutout for the buff. The plywood attaches to studs in the attic, and the fan attaches to the plywood. Some gable-mounted units arrive with a pre-fabricated metal base.
An attic fan will typically need 4 to 5 amps of service. A conventional 15-amp dwelling circuit can handle up to 10 electric boxes that service a mild or electric outlet. Homes using a 20-amp circuit can handle up to 13 boxes. In case an existing circuit nearby cannot deal with the additional load of the attic fan, you might need to conduct a new 15-amp circuit into the space. The fan will also require electrical connections to power it along with the thermostat to control when the fan runs. If you’re not familiar with creating electrical connections or running circuits, then contact an electrician.
Your attic fan should have a firestat for part of its structure. This system closes down an operating attic fan when it detects extremely substantial temperatures. This is a security consideration in case of a fire. Should the attic fan continue to function during a fire, it could create a draft that would create the blaze to spread fast.