Cfm For Bath Fan

To arrive at your required cfm simply divide your bathroom s volume by 7 5.

Cfm for bath fan.

Bathroom vent fans are rated for the amount of air they can move measured in cubic feet per minute or cfm. The result is the cfm or cubic feet per minute rating required for your bathroom fan. Enter bathroom length ft. In general for rooms with 8 foot ceilings.

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. A fan that s too small won t remove moisture and odors efficiently and will need to run longer increasing wear on the motor. Determine the required cfm for your bathroom fan. The bath fan calculator is standard guide to help you find the minimum fan rating for your specific bathroom.

The rule of thumb is that you need at least 1 cfm per square foot of room area. For example a bathroom with a volume of 1000 cubic feet 28 3 cubic meters needs a fan capable. Press calculate minimum suggested bath fan cfm. Suggested cfm for the bathroom is based on cycling all the air in the bathroom 8 times per hour.

A 50 square foot or smaller bathroom needs a 50 cfm fan. For bathrooms between 50 and 100 square feet estimate approximately 1 cfm per square foot. Enter bathroom height step 4. Enter bathroom width ft.

Standard fan sizing applies to bathrooms that are 100 square feet or less. The cfm represents the airflow required to completely exchange the air in your bathroom 8 times in one hour. Standard fan sizing.