What Size Exhaust Fan Do I Need For My Bathroom

Square feet is easy.

What size exhaust fan do i need for my bathroom.

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. Check the size of the exhaust port on the fan to make sure it fits your ductwork if applicable. Bathroom fans improve indoor air quality by venting moist air quickly outside which eliminates problems associated with high humidity like mold and mildew growth steamy mirrors and peeling wallpaper and paint. All you need to do is calculate the square feet of a room and the table tells you the cfm for either a kitchen or bathroom.

The fan pulls air out of the bathroom and allows fresh air to be drawn in. Bathroom extractor fans are mandatory in any bathroom without a window and still highly recommended in bathroom with windows. The formula to calculate bathroom exhaust fan size reads as follows. 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.

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. This keeps the moisture from the shower bath or sink from encouraging mold growth. Bathroom fan exhaust size calculator. Why you need a bathroom fan.

Handy table for fan values. A bathroom fan is an essential piece of hardware in any indoor bathroom without a window. A diameter of 4 inches. Higher ceilings would require a larger fan.

Never vent a bathroom fan directly into an attic it must always vent outside. The following table does lots of the math for you. Why you need to have the proper size extractor fan. Moist air from showers tubs and other fixtures in a bathroom can accumulate on bathroom surfaces leading to rot and peeling paint and providing a good environment for mold and mildew growth.

This guide will help you understand how to choose the right size and type of bathroom fan. Tam asks what size exhaust fan should we use in our small bathroom if your bathroom has an 8 ceiling the cubic feet per minute cfm rating for your fan should be as high or higher than the number of square feet in the room. Click here to get free fast bids from local contractors that install ventilation fans. Read on to find out more.