Cfm Rating Bathroom Exhaust Fan

A second fan may be needed.

Cfm rating bathroom exhaust fan.

Cubic volume 7 5 cfm necessary. Determine the size of your bathroom with this formula. The cfm number should be equal to or higher than the listed square footage of the bathroom an exhaust fan is being installed in i e. Length x width x height x 0 13 minimum.

A fan should have a cfm rating high enough to replace the air in your bathroom at a rate 8 times per hour. A fan s ability to move air is measured in cubic feet per minute cfm. A bathroom exhaust fan that is rated 50 cfm is ok to use in bathrooms that are 50 square feet or smaller. Therefore a bathroom with an area of 70 square feet needs a fan with a minimum cfm rating of 70.

The formula to calculate bathroom exhaust fan size reads as follows. The result is the cfm or cubic feet per minute rating required for your bathroom fan. I installed a 5 duct fan for bathroom exhaust the total length of duct to outside is less than 6 ft. Purchase a bathroom fan with the required cfm rating or higher.

The fan won t even push the damper open even with the spring on the exhaust damper removed. The cfm represents the airflow required to completely exchange the air in your bathroom 8 times in one hour. Fan ratings typically run between 50 and 110 cfm. The bigger your bathroom the higher the cfm rating you ll need.

If the enclosed space is small a 50 cfm fan should suffice. Another bathroom exhaust fan of the type purchased by commercial establishments pulls 470 cfm at the cost of 8 0 sones. Bathroom extractor fans are mandatory in any bathroom without a window and still highly recommended in bathroom with windows. After calculating your required cfm make sure to check the rating of any fan your purchase.

If your bathroom has a toilet or shower area enclosed by a door it s a good idea to install a separate exhaust fan for that area. Otherwise use the appropriate calculation based on the room size. So if you have a bathroom that is 12 feet long 15 feet wide and 10 feet tall then it has a volume of 1800 cubic feet 12 x 15 x 10 and a cfm of 240. The duct fan is rated 120 cfm free air.

With larger rooms at least one cfm for each square foot is required. The exhaust fan removes moisture and humidity from your bathroom. The appropriate size fan for a bathroom can replace the room s air. Just remember that the fan needs airflow to do its job.

1 panasonic fv 11vq5 whisperceiling bathroom exhaust fan review. A bathroom that is 50 square feet or less needs a 50 cfm fan. Its cfm per sone rating is 0 0800 about 20 times less efficient on a cfm per sone basis than the whisperquiet and higher than most other bathroom fans on the market.