Attic Exhaust Fan Sizing

Well managed indoor air quality is crucial to code compliance.

Attic exhaust fan sizing.

Cfm cubic feet per minute is a measure of the amount of air the fan moves in a minute. Powered exhaust vents feature an electric or solar powered fan to create an effect similar to that of a turbine view example on amazon. Our installer friendly energy star ventilation solutions help you design beyond code without compromising interior aesthetics. Those vents would give you 9 square feet of vent area which meets the venting need.

Attic vent fans are designed either to fit over a hole cut in your roof or to mount to the inside of a gable vent. During the summer an attic can be 40 to 50 hotter than the outside temperature which in turn heats up the house very quickly. Quietcool attic fans work almost everywhere almost anytime. The result is a cooler attic space with plenty of air exchange.

Attic fans perform this ventilation by pushing hot air out into the environment while also pulling fresh cool air into the attic. A standard powered. That translates to one attic vent 3 feet by 3 feet or two attic vents each 1 feet by 1 feet. How attic ventilation works.

To determine what size power vent fan s you need for your attic you first need to know the size of your attic in square feet. The formula above gives an approximate value of the cfm needed for an attic fan. 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. Attic fan size cfm 0 7 x sq ft area of the attic formula 1 the size of an attic fan is calculated in terms of cfm.