Cfm Meaning Bathroom Fan

A 50 cfm rating is recommended as a minimum for bathrooms 50 sq.

Cfm meaning bathroom fan.

Cfm is key when determining a fan s airflow efficiency. This keeps the moisture from the shower bath or sink from encouraging mold growth. For most bathrooms this works out to one cfm per square foot of bathroom area. A cfm of 75 is the minimum number to make a fan efficient.

Why you need to have the proper size extractor fan. The effectiveness of the fan will be rated in cfm or. The result is the cfm or cubic feet per minute rating required for your bathroom fan. Vent fans are rated by the number of cubic feet of air they move per minute cfm and it s important to buy a large enough fan for the size of your bathroom.

Bathroom extractor fans are mandatory in any bathroom without a window and still highly recommended in bathroom with windows. Cfm is the acronym for cubic feet per minute the measure of air volume moved by the fan blower. To be effective a bathroom fan needs to be powerful enough to completely replace the air in the room about 8 times every hour. 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 exhaust fan removes moisture and humidity from your bathroom. In the case of a blower or fan it indicates how much air it can move per minute. 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.

Larger bathrooms require additional ventilation capacity. So for example a 1 000 cfm fan can remove all of the air from a box that is 10ft x 10ft x 10ft in one minute. Bathroom vent fans serve an important function by removing humid air from your home to prevent mold and mildew from forming. The following chart can be used as a guide for proper bathroom.

If a bathroom is 8 x 8 with 8 ceiling that equals 512 cubic feet. For example a 7 x 10 bathroom would require a 70 cfm fan. The fan pulls air out of the bathroom and allows fresh air to be drawn in. You could have a fan that moves a lot of air with a high cfm but does so at a high wattage.

The cfm represents the airflow required to completely exchange the air in your bathroom 8 times in one hour.