Help determine optimal sizing of solar attic fans.
How to size solar attic fan.
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.
Attic fan size calculator this attic ventilation calculator computes the size and number of solar powered attic fans to achieve the proper ventilation for your attic.
A steep roof will increase internal attic volume and a dark roof will increase energy absorption from the sun.
The formula above gives an approximate value of the cfm needed for an attic fan.
Ft of your home by 0 7 will give you an approximate minimum cubic feet of air a fan should be able to move per minute.
If you do this you don t need to enter a length or width.
The warm air escapes through the attic and to the attic vents allowing the circulation of chilly air from the windows.
Too high of a cfm and you ll be spending.
It helps to cool your home temperatures and the attic by approximately 30 degrees.
Use this estimator to help figure out how many attic fans you will need.
To start enter the length width and height of your attic.
Alternatively for more precise calculations you can provide your actual floor area.
Choose a fan that matches your home or attic s size for optimal performance.
The whole house fan is installed inside the attic between the living space and ceiling.
Vent fan size next multiply the square feet of attic space by 0 7 to get the minimum number of cubic feet of air per minute that the fan should be rated to move.
Whole house fans work on the principle of removing the hot and humid air out of the house.
Solar attic fan sizing calculator.
Cfm cubic feet per minute is a measure of the amount of air the fan moves in a minute.
Attic x 0 7 700 cfm minimum fan rating add an additional 20 cfm x 1 20 if you have a steep roof and 15 cfm x 1 15 for a dark roof.