Exhaust Fan Cfm Chart

You could have a fan that moves a lot of air with a high cfm but does so at a high wattage.

Exhaust fan cfm chart.

Learning how to calculate cfm for a bathroom fan will help you purchase the right size fan for your space. Airflow efficiency is the cfm divided by the watts amount of energy used to run the fan at its highest speed. If i can find a y pipe with a 4 and a 6 entry what size should the exit pipe be. Cubic volume 7 5 cfm necessary.

100 cfm fan with a 4 exhaust port and back flow flap. The second fan is 150cfm with the ability to have a 4 or 6 vent pipe attached. To be effective a bathroom fan needs to be powerful enough to completely replace the air in the room about 8 times every hour. The minimum allowed fan size is 50 cfm so if your bathroom is for example only 42 square feet you still need a 50 cfm fan.

Bathroom fan exhaust size calculator. The formula to calculate bathroom exhaust fan size reads as follows. The effectiveness of the fan will be rated in cfm or cubic feet per minute of air moved. 10ft 10ft 8ft 7 5 106 67 cfm.

For a standard 10ft by 10 ft bathroom with an 8 ft ceiling you will need an exhaust fan capable of 106 67 cfm. If you are not sure what kind of cfm s may be needed for your type of facility please refer to the commercial industrial applications chart below. Here s how we get this number. Cfm is key when determining a fan s airflow efficiency.