How To Size An Attic Fan

The warm air escapes through the attic and to the attic vents allowing the circulation of chilly air from the windows.

How to size an attic fan.

How to size a whole house attic fan. To find out if you have enough vent space divide the cubic feet of air per minute that the fan is rated for by 300 to come up with the minimum number of square feet of intake vent space needed for that size fan. A whole house fan sucks warm house. This attic ventilation calculator computes the size and number of solar powered attic fans to achieve the proper ventilation for your attic.

An attic fan works by exchanging the hot air in your attic space for fresh air pulled through the vents. Attic fan size calculation. Cfm cubic feet per minute is a measure of the amount of air the fan moves in a minute. Help determine optimal sizing of solar attic fans.

A whole house attic fan is installed in the ceiling between the top floor and the attic as a supplement to air conditioning. Simultaneously cool fresh air will be pulled through the open windows and circulated through every room effectively replacing all of the air in your home and minimizing your dependence on air conditioning. How to size solar attic exhaust vent fans so we developed our solar powered attic fan sizer calculator. Whole house fans work on the principle of removing the hot and humid air out of the house.

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. By sizing and implementing a whole house fan you can pull the warm stale air from your entire home into the attic where it s vented outside. It helps to cool your home temperatures and the attic by approximately 30 degrees. The whole house fan is installed inside the attic between the living space and ceiling.

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.