Attic Gable Fan Sizing

Example 20 wide by 50 long attic.

Attic gable fan sizing.

Cfm cubic feet per minute is a measure of the amount of air the fan moves in a minute. Building codes vary. This attic ventilation calculator computes the size and number of solar powered attic fans to achieve the proper ventilation for your attic. Always have a balanced ventilation system.

To determine the size of your attic multiply the width by the length of the attic floor in feet. Of vent for every 300 sq. Help determine optimal sizing of solar attic fans. Temp 92 f at 5pm.

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 model can be installed through the wall. The attic fan kept my house cooler by 8f compared to pre fan installation days. Temp 84f at 5pm.

The opening of the boom mouth must be large enough for the attic fan to consume the hot air from the attic. Gable fans will be rated for a certain amount of free space ventilation. 20 x 50 1 000 sq. The formula above gives an approximate value of the cfm needed for an attic fan.

For a single story house this is usually the same as the square footage of the house itself plus any attached garage area. 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. If you ve got access to your attic s gables iliving s gable mount fan is a great option for moving some air without having to cut a hole in your roof. During workdays would leave air conditioner off when leaving in the morning.

In order to facilitate this exchange of warm and cool air the general rule of thumb suggests installing at least 1 sq. This was observed on numerous days following the installation.