Multiply the blade length by two and add that measurement to the hub diameter from step 3 to determine your total fan diameter.
How do you measue for a attic fan.
Ceiling fans come in a variety of sizes ranging from 30 inches for small rooms to 70 inches for larger rooms.
Measure the length and width of each floor of your home with the tape measure.
One of the most asked questions we get is what size whole house fan do i need.
Next multiply the square feet of attic space by 0 7 to get the minimum number of cubic feet of air per.
The formula above gives an approximate value of the cfm needed for an attic fan.
Finding the right sized whole house fan for your home.
Then click on calculate.
Multiply the total air volume in cubic feet by 30 which represents a complete air change every 2 minutes.
Option 1 moderate flow efficient cooling 1 5 2 0 cfm of air flo.
Calculate the required cfm air flow.
Select if your roof is more flat of peaked.
How to size a whole house attic fan.
More importantly though you ll need to choose the right size ceiling fan according to the size of the room.
I know the dimensions of my attic space.
Multiply length times.
And then add insulation if your attic does not have the recommended levels.
For heating and air conditioning airflow or for other exhaust fan situations see our airflow calculator.
You can also view my blog post about attic air sealing here as well as a great article from a well respected professional in the home performance industry about power attic ventilators here.
Its a matter of personal preference.
They can cool your home in less than an hour.
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 enter the height at the highest point.
They can cool your home in less than an hour.
A typical fan can t do both the work of an attic and the whole house fan but a whole house fan does both.
You can size a whole house fan for either a moderate flow or the breeze effect.
For open blade fans see our ceiling fan calculator.
You want to make the ceiling plane is as air tight as possible.
Enter the length and width of your attic or ceiling crawl space.
Cfm cubic feet per minute is a measure of the amount of air the fan moves in a minute.
Attic fan size calculation.
Measure the length of one blade from tip to base.
Find the overall air volume of your home.
Fans that measure 52 inches are the most commonly used.
You can check the recommended levels of insulation for your region on the energy star website here.
How to size attic exhaust vent fans for your home attic size.
