How Many Cfm Attic Fan Move

The quietcool afg pro 3 0 attic gable fan can help cool and ventilate your attic for just pennies an hour.

How many cfm attic fan move.

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. Add an additional 20 cfm x 1 20 if you have a steep roof and 15 cfm x 1 15 for a dark roof. Attic fan size calculation. Ft of attic space for example 20 x 50 to be effective.

Below we list the top box fans cfm. High cfm fan buying guide. To facilitate faster air exchange would necessitate choosing a fan with a higher cfm. For bathrooms 50 square feet and smaller it is recommended you purchase a bath fan designed for small rooms which will typically have a cfm range of 50 79.

Fan cfm calculator this fan calculator is typically used to calculate the cfm or cubic feet per minute of air exchange that may be desired in a building. The formula above gives an approximate value of the cfm needed for an attic fan. Many are solar powered and require no other wiring so they don t cause any additional charges on your electricity bill at all. According to the home ventilating institute hvi powered attic ventilators need to move a minimum of 700 cubic feet per minute cfm for 1 000 sq.

Attic x 0 7 700 cfm minimum fan rating. For proper cooling and efficient operation any whole house comfort ventilator requires adequate unobstructed outlets in the attic through soffit vents grilles or louvers. So as another example moving to a 2500 cfm fan would cut the air exchange time to roughly 7 minutes 17 600 2500. Fans are sold on the basis of diameter or the cfm of air they move.

Cfm cubic feet per minute is a measure of the amount of air the fan moves in a minute. Running at 250 watt and moving over 2860 cfm this fan uses less power than typical attic fans that move half the amount of cfm. To calculate the amount of attic exhaust area you will need divide the fan s capacity in cfm by 750. For example a typical 36 inch diameter whole house fan will move 6 900 cfm of air.

Most fans are rated from 50 to 110 cfm. Whether exhausting air or bringing fresh air into a structure the calculation produced should help to figure out the size of fan s required to accomplish the air exchanges needed. Attic vent fans are commonly. Box fan cfm can vary depending of the size of the fan.

For a 20 box fan the cfm can range from around 1000 cfm up to 2500 cfm. A 30 inch fan will move 5 700 cfm. The afg pro 3 0 is possibly the most powerful residential attic fan on the market today. 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.