Sizing Attic Ventilation Fans

Example 20 wide by 50 long attic.

Sizing attic ventilation fans. Minimum intake air vent size cfm 300 sq ft. So here the cfm of the fan cfm x 1 15. If your attic requires a 1500 cfm fan then it should also have a 1500 300 5 sq ft air vent. 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.

20 x 50 1 000 sq. Intake air vent size. They are typically easier to install and won t detract from the appearance of your roof. Our installer friendly energy star ventilation solutions help you design beyond code without compromising interior aesthetics.

For the exhaust to work properly the attic should have enough intake air vents. A whole house attic fan is installed in the ceiling between the top floor and the attic as a supplement to air conditioning. 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.

See the benefits of attic ventilation a new roof is more than just shingles. How to size a whole house attic fan. 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. 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.

Master flow egv5 gable mount attic ventilators are master flow egv5 gable mount attic ventilators are a great choice for exhaust ventilation. This attic ventilation calculator computes the size and number of solar powered attic fans to achieve the proper ventilation for your attic. 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.