What Size Should My Bathroom Ventilation Fan Be? 07/28/2017Ordinary tasks like showering, bathing and shaving can put home-damaging humidity into the air in your Pinellas County home. There’s good news however—a simple bathroom ventilation fan can keep you from deformed wood, mold growth, cracked 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 right size? Are they as quiet and energy efficient as they could be? Hale's Air Conditioning Services Inc is here to answer your questions. Today’s bathroom ventilation fans are small and smooth and they run more quietly and efficiently than ever before. You’ll find a large range of selections, from simple fans that will get the job done to fans with built-in heat lamps, motion sensors and heat-exchanger ventilation that helps block warmed air from escaping through your ventilation. While you have 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 swap out the air in a bathroom at least eight times an hour. With a normal 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 taller ceiling, the equation gets a little more complex. 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 – 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 unsure if your bathroom ventilation fan is the correct size, or you know it’s time for a new one, give the pros at Hale's Air Conditioning Services Inc at call at 727-398-5515. We’re here to help you guarantee you have a ventilation fan that will run hard to care for your home and keep it cozy. You can even arrange an appointment with us online if that’s easiest for you.