Exhaust Fan Cfm Chart

If i can find a y pipe with a 4 and a 6 entry what size should the exit pipe be.

Exhaust fan cfm chart.

Learning how to calculate cfm for a bathroom fan will help you purchase the right size fan for your space. A cfm of 75 is the minimum number to make a fan efficient. The effectiveness of the fan will be rated in cfm or cubic feet per minute of air moved. If you have any questions regarding cfm s air exchanges needed the calculator or which exhaust and or supply fans may be right for your building please call us at 866 727 1060.

Airflow efficiency is the cfm divided by the watts amount of energy used to run the fan at its highest speed. The formula to calculate bathroom exhaust fan size reads as follows. To be effective a bathroom fan needs to be powerful enough to completely replace the air in the room about 8 times every hour. 10ft 10ft 8ft 7 5 106 67 cfm.

Sizing for large bathrooms for bathrooms over 100 square feet exhaust fans can be sized according to the number of fixtures in the room. 100 cfm fan with a 4 exhaust port and back flow flap. Cfm is key when determining a fan s airflow efficiency. 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. 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. The second fan is 150cfm with the ability to have a 4 or 6 vent pipe attached. Cubic volume 7 5 cfm necessary.