Sizing Attic Ventilation Fans

Master flow egv5 gable mount attic ventilators are master flow egv5 gable mount attic ventilators are a great choice for exhaust ventilation.

Sizing attic ventilation fans.

For the exhaust to work properly the attic should have enough intake air vents. Our installer friendly energy star ventilation solutions help you design beyond code without compromising interior aesthetics. 20 x 50 1 000 sq. Minimum intake air vent size cfm 300 sq ft.

So here the cfm of the fan cfm x 1 15. Proper attic ventilation consists of a balance between air intake at your eaves soffits or fascias and air exhaust at or near your roof ridge. See the benefits of attic ventilation a new roof is more than just shingles. A whole house fan sucks warm house.

Well managed indoor air quality is crucial to code compliance. This attic ventilation calculator computes the size and number of solar powered attic fans to achieve the proper ventilation for your attic. Example 20 wide by 50 long attic. They are typically easier to install and won t detract from the appearance of your roof.

The result is a cooler attic space with plenty of air exchange. 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. Attic fans perform this ventilation by pushing hot air out into the environment while also pulling fresh cool air into the attic. Attic fan size chart for quick reference.

How to size a whole house attic fan. Next multiply the square feet of attic space by 0 7 to get the minimum number of cubic feet of air per minute that the fan should be rated to move. Effective attic ventilation systems reduce damaging heat and moisture in your attic promote energy efficiency by helping to reduce the load on your air conditioner in the summer and also reduce the risk of ice dam formation on your roof. A whole house attic fan is installed in the ceiling between the top floor and the attic as a supplement to air conditioning.