Attic Exhaust Fan Sizing

Attic fans perform this ventilation by pushing hot air out into the environment while also pulling fresh cool air into the attic.

Attic exhaust fan sizing.

How attic ventilation works. 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. 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. This attic ventilation calculator computes the size and number of solar powered attic fans to achieve the proper ventilation for your attic.

Powered exhaust vents feature an electric or solar powered fan to create an effect similar to that of a turbine view example on amazon. A standard powered. The formula above gives an approximate value of the cfm needed for an attic fan. Those vents would give you 9 square feet of vent area which meets the venting need.

Well managed indoor air quality is crucial to code compliance. Cfm cubic feet per minute is a measure of the amount of air the fan moves in a minute. 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. During the summer an attic can be 40 to 50 hotter than the outside temperature which in turn heats up the house very quickly.

Our installer friendly energy star ventilation solutions help you design beyond code without compromising interior aesthetics. With an attic fan you can cool the attic to the same temperature as it is outside greatly reducing the house from heating as quickly. That translates to one attic vent 3 feet by 3 feet or two attic vents each 1 feet by 1 feet. Quietcool attic fans work almost everywhere almost anytime.