What Size Should My Bathroom Ventilation Fan Be? 07/28/2017Average tasks like showering, bathing and shaving can put home-destructive humidity into the air in your Port Saint Lucie home. There’s good news however—a modest bathroom ventilation fan can protect you from deformed wood, mold growth, damaged drywall and other problems 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 soft and energy efficient as they could be? Custom Air Systems Inc is here to answer your questions. Today’s bathroom ventilation fans are small and modern and they work more quietly and economically than ever before. You’ll find a hefty range of options, 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 you can find a lot of bells and whistles to select from, the most important feature of your fan is whether or not it’s big enough to do its job. Rated by the cubic feet per minute (CFM) of air they push, a bathroom ventilation fan should be able to swap out the air in a bathroom at least eight times an hour. With a typical 8-foot ceiling, your ventilation fan should have a CFM rating at least as high as the number of square feet in your bathroom. So, 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 complicated. 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 tips for bathrooms larger than 100 square feet – establish your CFM requirements by adding 50 CFM for every toilet; 50 CFM for each shower, bath and combo; and 100 CFM for each whirlpool. If you’re unclear if your bathroom ventilation fan is the correct size, or you know it’s the occasion for a new one, give the pros at Custom Air Systems Inc at call at 772-335-3232. We’re here to help you make sure you have a ventilation fan that will work hard to care for your home and keep it cozy. You can even schedule an appointment with us online if that’s easiest for you.