Bathroom Vent Fan Cfm Calculator
This is how often your extractor fan should be able to replace the bathroom with fresh air.
Bathroom vent fan cfm calculator. By simply inputting into the calculator the dimensions of your room and the type of room application for the fan the calculator will provide you with a suggested general capacity range in cubic metres per hour m3 hr to help narrow down your exhaust fan options. So for an 80 square foot bathroom with a 10 foot ceiling you ll get the best results from a fan with a rating of at least 112 cfm. An effective bathroom fan should be capable of replacing the entire volume of air 8 times per hour or every 7 5 minutes.
The higher the bath fan rating the more air can be vented out of the bathroom which means less moisture and mold build up. In general to calculate cfm for your industrial exhaust application you need to know the total floor area of your space. All you need to do is select the application from the dropdown enter the size of the room and we will provide you with a general capacity range m3 hr that you should be looking to achieve from the extraction fan.
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. Other options for bath fans include lights heaters and even. This information is provided as a guide only.
Building code does not specify bathroom vent locations but in any size bathroom it is the most logical to install it over or as close as possible to the plumbing fixture that requires it. Suggested cfm for the bathroom is based on cycling all the air in the bathroom 8 times per hour. This page is designed to be a general guide for selecting an exhaust fan based on the size of the room and the type of application the fan will be used for.
Simply enter the dimensions of your bathroom in the calculator below to determine the minimum size vent fan you need for the bathroom in your home. For standard square or rectangular bathrooms you can use the formula length x width x height volume. Calculate how many cfm your bathroom fan needs by dividing the number from the step 2 by 7 5.
With this number divide it by multiply it by 0 1 to 1 to get you estimated cfm. The cfm represents the airflow required to completely exchange the air in your bathroom 8 times in one hour. The result is the cfm or cubic feet per minute rating required for your bathroom fan.
Divide the volume of your bathroom in feet by 7 5. Toilet 50 cfm shower stall 50 cfm whirlpool 100 cfm 200cfm bathroom exhaust fan. Determine the required cfm for your bathroom fan.
For example a 1000 square foot area may need a cfm exhaust fan of 1000 0 1 100 or 1000 1 1000. The bath fan calculator is standard guide to help you find the minimum fan rating for your specific bathroom.
