Because what happens is attic fans are so strong that they actually reach down into the conditioned space of your house and they do that by using the wall cavities and where the outlets and pipes come through the walls as places where they draw air from the inside of your house it s that air conditioned air and it ll pull it right up into the attic and exhaust it outside.
Doni need an attic fan.
Open your windows before you turn on the fan.
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.
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.
Cooler outdoor air enters through open windows lowering the indoor temperature.
So if your fan is rated at 1500 cfm you will need about two feet of totally open space in your attic.
Electric attic fans however often increase energy consumption and cancel out any savings unless the attic is not insulated at all.
Your home s roof and attic was most likely designed with just the right amount of fresh air it needs.
It doesn t matter if the ventilation openings are spread out as long as there is sufficient space for all the air to escape.
This fan moves 1 000 or more cubic feet of air per minute creating low pressure in your attic.
In the late evening or early morning the fan is turned on to exhaust hot air from the house.
To reduce that expense some homeowners buy an electric or solar attic ventilator.
Whole house fans need windows and doors open and attic fans need lots of soffit vents to suck.
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.
For both fans to work well they need large exhaust openings in the roof for the moving air to exit.
The main work of an attic fan is to regulate the heat level of the attic by removing hot air out of the attic and pushing it outside providing needed ventilation.
Soffits gable vents without fans and rafter vents are passive ventilation systems to keep your roof and attic healthy.
A whole house fan is usually installed on the attic floor near the center of your house.
That means two feet of open space.
A ridge vent is an opening along the ridge of your roof.
Note that these two feet would not need to be one large opening.
Studies have shown if your attic is properly ventilated with a ridge vent and your attic is well insulated you wouldn t need an attic fan.