However there are certain circumstances where they can prove useful.
Are attic fans worth it.
If the attic fan increases the comfort level of the house it may be worth it.
These fans are designed to remove excess heat from your attic which in theory is supposed to lessen the load on the air conditioning in your home.
How an attic fan works.
Do not use mechanical means electric attic fans.
Attic ventilation fans could be effective if your home has.
Attic fans exhaust hot air from your attic to the outside.
Venting a homes attic is a very important best building practices will say 50 at the ridge and 50 at the soffits unobstructed.
This is a solar panel supplying free electricity to the attic fan under the silver dome on the rear roof.
The fan blades spin but they don t lower the attic.
Attic insulation that is less than r 19.
As a certified licensed home inspector it is not correct to say too much ventilation is bad for an attic unless rain moisture is getting in.
It may be starting to sound like attic ventilation fans aren t worth the hassle and could cause more problems than they solve.
If there isn t enough venting in the attic for the attic fan to pull air from it will start pulling air from the home s interior through the wall cavities and drywall ceilings.
Instead of installing a fan just make sure your attic is well ventilated.
Much of that heat then conducts downward and finds its way into the house.
The attic fans needs to have a minimum amount of makeup air or intake air which is the vent area that the attic fan pulls air from.
Find out whether it is economical to run an attic fan.
If the attic fan keeps the house cool enough so that the owners leave the ac off there is almost certainly an energy benefit.
Or is it better to abide by proven methods of insulating a home and increasing attic ventilation through soffits ridge vents or offset ridge vents.
An attic fan is installed on the slanted side of your roof or on one of the gable sides of your attic.
So is it truly worth it to add a solar attic fan on an older home.
Of course if the attic fan isn t working correctly and is running all year long that would be a significant problem.
Attic fans are not recommended if you have central air conditioning because when you turn the fan on in the summer it depressurizes the attic but also reaches down into your house and starts drawing off air conditioned air effectively driving up your cooling costs.
Solar attic fans are not needed in brand new construction homes.
Using a fan to blow hot air out of the attic doesn t address the radiant heat flow from the roof to the attic floor.