Sizing Attic Ventilation Fans

The result is a cooler attic space with plenty of air exchange.

Sizing attic ventilation fans.

20 x 50 1 000 sq. Minimum intake air vent size cfm 300 sq ft. A whole house attic fan is installed in the ceiling between the top floor and the attic as a supplement to air conditioning. 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.

So here the cfm of the fan cfm x 1 15. Intake air vent size. They are typically easier to install and won t detract from the appearance of your roof. 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.

A whole house fan sucks warm house. 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. They can quickly remove a larger volume of hot and or humid air from your attic compared to static ventilation which helps save money on your heating and cooling.

If your attic requires a 1500 cfm fan then it should also have a 1500 300 5 sq ft air vent. This attic ventilation calculator computes the size and number of solar powered attic fans to achieve the proper ventilation for your attic. For the exhaust to work properly the attic should have enough intake air vents. 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.

How to size a whole house attic fan. Well managed indoor air quality is crucial to code compliance. Example 20 wide by 50 long attic. Master flow egv5 gable mount attic ventilators are master flow egv5 gable mount attic ventilators are a great choice for exhaust ventilation.