Cfm Fan For Bathroom Size

The result is the cfm or cubic feet per minute rating required for your bathroom fan.

Cfm fan for bathroom 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 1800 7 5. For example a bathroom with a volume of 1000 cubic feet 28 3 cubic meters needs a fan capable of moving 1000 7 5 or 133 cfm 3 8 cubic meters per minute. Hi tam bathroom vent fans are rated by the cubic feet per minute cfm of air they move and should be sized to replace the air in the room at least eight times an hour. If your bathroom has an 8 ceiling the cfm rating for your fan should be as least as high as the number of square feet 5 x 7 35 sq.

Sizing for large bathrooms for bathrooms over 100 square feet exhaust fans can be sized according to the number of fixtures in the room. Press calculate minimum suggested bath fan cfm. If all else fails check the packaging. It is based on hvi home ventilating institute guidelines that recommend approximately 8 room air exchanges per hour for a bathroom under 100 square feet of area.

Most fans are rated from 50 to 110 cfm. 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. Determine the size of your bathroom with this formula. The cfm represents the airflow required to completely exchange the air in your bathroom 8 times in one hour.

Divide the volume of your bathroom in feet by 7 5. Enter bathroom width ft. Enter bathroom height step 4. The bath fan calculator is standard guide to help you find the minimum fan rating for your specific bathroom.

Each bath fan will indicate the maximum square footage it can t ventilate. Cfm cubic feet per minute general term used to specify the amount of air that the bathroom fan is able to move within one minute of its operation. Suggested cfm for the bathroom is based on cycling all the air in the bathroom 8 times per hour. Enter bathroom length ft.

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. To arrive at your required cfm simply divide your bathroom s volume by 7 5. So in your case a 50 cfm fan should work. When installing a vent fan make sure there s at least a 1 2 gap under the bathroom door to allow fresh air to enter the room when the fan is running.

Length x width x height x 0 13 minimum cfm rating.