What Size Should My Bathroom Ventilation Fan Be? 07/28/2017Average tasks like showering, bathing and shaving can put home-harming humidity into the air in your Stuart home. There’s good news however—a modest bathroom ventilation fan can save you from deformed wood, mold growth, broken drywall and other trouble connected with a humid bathroom. Even if you have ventilation fans in your bathrooms, do you know if they’re the correct size? Are they as noiseless and energy efficient as they could be? Nisair Air Conditioning is here to answer your questions. Today’s bathroom ventilation fans are small and sleek and they operate more quietly and efficiently than ever before. You’ll find a hefty range of choices, from simple fans that will get the job done to fans with fitted heat lamps, motion sensors and heat-exchanger ventilation that helps avoid warmed air from getting out through your ventilation. While there are a lot of bells and whistles to pick from, the most imperative aspect of your fan is whether or not it’s large enough to do its job. Rated by the cubic feet per minute (CFM) of air they move, a bathroom ventilation fan should be able to replace the air in a bathroom at least eight times an hour. With a standard 8-foot ceiling, your ventilation fan should have a CFM rating at least as high as the number of square feet in your bathroom. Thus, if your bathroom is 5 feet by 8 feet, a CFM rating of 40 would be satisfactory. If you have a higher ceiling, the equation gets a little more difficult. You’ll want to multiply the width of the room by its height and length, divide it by 60 and multiply by 8. Or, to keep it easy, you can follow HGTV’s guidance for bathrooms larger than 100 square feet – determine your CFM requirements by toting 50 CFM for every toilet; 50 CFM for each shower, bath and combo; and 100 CFM for each whirlpool. If you’re not sure if your bathroom ventilation fan is the right size, or you know it’s time for a new one, give the professionals at Nisair Air Conditioning at call at 772-318-4252. We’re here to help you make sure you have a ventilation fan that will run hard to guard your home and keep it cozy. You can even schedule an appointment with us online if that’s easiest for you.