How Many Cfm Attic Fan Move

The most powerful box fan available is the lasko 3723 which has 2500 cfm.

How many cfm attic fan move.

Most fans are rated from 50 to 110 cfm. A 30 inch fan will move 5 700 cfm. Below we list the top box fans cfm. 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.

Many are solar powered and require no other wiring so they don t cause any additional charges on your electricity bill at all. Another way to look at this is to calculate how many air exchanges are performed in an hour for a fan with a certain cfm. For bathrooms that are larger select a fan that can move at least 1 cfm per square foot of room. Attic vent fans are commonly.

Fans are sold on the basis of diameter or the cfm of air they move. Ft of attic space for example 20 x 50 to be effective. To facilitate faster air exchange would necessitate choosing a fan with a higher 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.

For proper cooling and efficient operation any whole house comfort ventilator requires adequate unobstructed outlets in the attic through soffit vents grilles or louvers. For a 20 box fan the cfm can range from around 1000 cfm up to 2500 cfm. 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. 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.

For example a typical 36 inch diameter whole house fan will move 6 900 cfm of air. Box fan cfm can vary depending of the size of the fan. 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. Cfm cubic feet per minute is a measure of the amount of air the fan moves in a minute.

The afg pro 3 0 is possibly the most powerful residential attic fan on the market today. The formula above gives an approximate value of the cfm needed for an attic fan. High cfm fan buying guide. To calculate the amount of attic exhaust area you will need divide the fan s capacity in cfm by 750.

Attic fan size calculation. 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. Attic x 0 7 700 cfm minimum fan rating. So as another example moving to a 2500 cfm fan would cut the air exchange time to roughly 7 minutes 17 600 2500.