Do I Need An Attic Exhaust Fan

Attic ventilation fans help cool air your attic by pushing out the stifling hot air from inside the attic and bringing in cool air from outside.

Do i need an attic exhaust fan.

Unlike a ventilation fan a whole house fan an attic mounted fan that exhausts air from a home at night is designed to cool a house that is to lower the indoor temperature. Ok i would definitely not recommend an attic fan. Generally speaking you need a ratio of 1 300 where for every 300 square feet of ceiling space you need 1 square foot of attic ventilation. It doesn t matter if the ventilation openings are spread out as long as there is sufficient space for all the air to escape.

As long as you have enough space at the base of the roof for an equal amount of soffit vents you shouldn t need a fan. That said air resistance and interference such as vent grates reduces the area of true ventilation. This prevents hot air from seeping into your home and driving up the temperature in the living space which reduces the load on your air conditioner. Whole house fans need windows and doors open and attic fans need lots of soffit vents to suck.

That means two feet of open space. Without exception you should talk to a professional to determine what your home requires. So if your fan is rated at 1500 cfm you will need about two feet of totally open space in your attic. For both fans to work well they need large exhaust openings in the roof for the moving air to exit.

A fan might be necessary if the construction of your house is such that you. Attic fans exhaust hot air from your attic to the outside. A powered attic ventilator has a different purpose. Intake vents located at the lowest part of the roof under the eaves allow cool.

It is designed to lower the temperature of an attic by exhausting air from the attic and replacing attic air with outdoor air. This air is then exhausted through the fan to the outside. Note that these two feet would not need to be one large opening. Attic ventilation works on the principle that heated air naturally rises primarily utilizing two types of vents.