How Much Attic Fan Do I Need

Federal housing authority recommends a minimum of at least 1 square foot of attic ventilation evenly split between intake and exhaust for every 300 square feet of attic floor space.

How much attic fan do i need.

It might cost you approximately 300 600 for purchase and up to 550 when you include labor. Attic fans exhaust hot air from your attic to the outside. You need a minimum of 1 square foot of attic air venting for each 750 cfm of air flow. When i last had a new roof installed a few years ago i calculated the soffit intake area i d need for the ridge vent specs.

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. Attic fans are cheap compared to whole house fans. The moving air tries to cool down all the wood attic framing as without the fan the temperature. How an attic fan works.

A 1500 square feet attic would cost 70 with additional humidistat costing 15. Ft of attic space for example 20 x 50 to be effective. According to the home ventilating institute hvi powered attic ventilators need to move a minimum of 700 cubic feet per minute cfm for 1 000 sq. Professional help labor of 40 then the total would be 125.

Ideally there should also be plenty of soffit intake space their calculations recommend 336 net square inches of open soffit ventilation to supply 700 cfm. All you need to know about attic ventilation. An attic fan is installed on the slanted side of your roof or on one of the gable sides of your attic. If you live in the right climate whole house fans are a great way to keep your house cool day and night and only use about 10 to 15 of the power drawn by a central air conditioner.

Attic vent fans are commonly rated from 800 to 1 600 cfm making one fans suitable for attics of up to around 2 200 square feet. Powered exhaust vents feature an electric or solar powered fan to create an effect similar to that of a turbine view example on amazon. If you want your home air conditioner to cool you better then you might want one or two attic fans. Attic x 0 7 700 cfm minimum fan rating add an additional 20 cfm x 1 20 if you have a steep roof and 15 cfm x 1 15 for a dark roof.

I had my attic floor sealed and a good amount of blown in insulation. Yet i still see the attic temperature reach 145 degrees.