Buyers Tip: Choose a fan that can move at least 1 CFM per square foot of room. For example, for a 50-79 sq. ft. bathroom, select a fan with a 50 to 80 CFM rating. Related Products. 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. For bathrooms that are larger, select a fan that can move at least 1 CFM per square foot of room. Bath Fans by Room Size Buyers Tip: Choose a fan that can move at least 1 CFM per square foot of room. For example, for a 50-79 sq. ft. bathroom, select a fan . Bathroom exhaust fans perform multiple duties in your home. From removing . Home Depot compiled a simple formula to determine the size of your bathroom:. Select the best bathroom fan for removing excess moisture and save your space . your bathroom and use the following mathematical formula from Home Depot:. Are you struggling with finding the right bathroom fan for you? . in inches) for your home. Other tips: Existing Wiring: Consider installing a fan with light over an . Shop a variety of bathroom exhaust fans and parts at Lowe’s ranging from Panasonic bathroom fans to bath fans with lights and Bluetooth speakers. 18 sept. 2012 – Choose the best bathroom fan for your needs with these tips. . The Home Ventilating Institute recommends one CFM per square foot of .