Enter the length and width of your attic or ceiling crawl space.
How to size an attic fan.
How to size attic exhaust vent fans for your home attic size.
Next multiply the square feet of attic space by 0 7 to get the minimum number of cubic feet of air per.
Some professionals multiply the square feet value with 0 6 instead of 0 7.
It helps to cool your home temperatures and the attic by approximately 30 degrees.
The warm air escapes through the attic and to the attic vents allowing the circulation of chilly air from the windows.
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.
Select if your roof is more flat of peaked.
The whole house fan is installed inside the attic between the living space and ceiling.
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.
Then click on calculate.
Find the overall air volume of your home.
Always have a balanced ventilation system.
This is a quick rundown of the different types of attic fans their most common features and.
Measure the length and width of each floor of your home with the tape measure.
Multiply length times.
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.
How to size a whole house attic fan.
Without an attic fan the temperature in your attic can climb to a searing 150 degrees.
The formula above gives an approximate value of the cfm needed for an attic fan.
I know the dimensions of my attic space.
Attic fan size calculator step 1.
Cfm cubic feet per minute is a measure of the amount of air the fan moves in a minute.
To determine the size of your attic multiply the width by the length of the attic floor in feet.
Whole house fans work on the principle of removing the hot and humid air out of the house.
Multiply the total air volume in cubic feet by 30 which represents a complete air change every 2 minutes.
Calculate the required cfm air flow.