Attic Gable Fan Sizing

Help determine optimal sizing of solar attic fans.

Attic gable fan sizing.

Temp 84f at 5pm. Example 20 wide by 50 long attic. During workdays would leave air conditioner off when leaving in the morning. This attic ventilation calculator computes the size and number of solar powered attic fans to achieve the proper ventilation for your attic.

The formula above gives an approximate value of the cfm needed for an attic fan. To determine the size of your attic multiply the width by the length of the attic floor in feet. Always have a balanced ventilation system. Building codes vary.

How to size solar attic exhaust vent fans so we developed our solar powered attic fan sizer calculator. Of vent for every 300 sq. This model can be installed through the wall. This indicates the amount of ventilation area independent of the gable opening where the fan is installed.

Gable fans will be rated for a certain amount of free space ventilation. The opening of the boom mouth must be large enough for the attic fan to consume the hot air from the attic. This was observed on numerous days following the installation. After attic fan installation ac still off during day.

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. 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. Cfm cubic feet per minute is a measure of the amount of air the fan moves in a minute.

Temp 92 f at 5pm. In order to facilitate this exchange of warm and cool air the general rule of thumb suggests installing at least 1 sq.