Bathroom Exhaust Fan Specifications. If your bathroom is larger than 100 square feet tally the cfm requirements for the individual fixtures to estimate your needs. Some signs of excessive uncontrolled bathroom moisture include. Here s how we get this number.
To arrive at your required cfm simply divide your bathroom s volume by 7 5. Multiply the bathroom floor area in square feet by 1 07.
Bathroom select a fan with a 50 to 80 cfm rating.
An effective bathroom fan should be capable of replacing the entire volume of air 8 times per hour or every 7 5 minutes. Bathroom select a fan with a 50 to 80 cfm rating. 50 cubic feet per minute cfm intermittent or 20 cfm continuous. Choose a fan that can move at least 1 cfm per square foot of room.
