What Size Should My Bathroom Ventilation Fan Be? 07/28/2017Average tasks like showering, bathing and shaving can put home-damaging humidity into the air in your Tuscaloosa home. There’s good news however—a straightforward bathroom ventilation fan can keep you from distorted 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 noiseless and energy efficient as they could be? KDM Service Corporation 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 great range of options, from classic fans that will get the job done to fans with integrated heat lamps, motion sensors and heat-exchanger ventilation that helps avoid warmed air from leaking through your ventilation. While you have a lot of bells and whistles to pick from, the most important feature of your fan is whether or not it’s full-sized enough to do its job. Graded 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. Therefore, if your bathroom is 5 feet by 8 feet, a CFM rating of 40 would be sufficient. 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 simple, you can follow HGTV’s advice for bathrooms larger than 100 square feet – determine 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 proper size, or you know it’s time for a new one, give the pros at KDM Service Corporation at call at 205-758-2703. We’re here to help you ensure you have a ventilation fan that will run hard to guard your home and keep it comfortable. You can even schedule an appointment with us online if that’s the most straightforward for you.