What Size Should My Bathroom Ventilation Fan Be? 07/28/2017Ordinary tasks like showering, bathing and shaving can put home-harming humidity into the air in your Dresden home. There’s good news though—a simple bathroom ventilation fan can keep you from warped wood, mold growth, cracked 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 proper size? Are they as soft and energy efficient as they could be? McFadden Heating & Cooling is here to answer your questions. Today’s bathroom ventilation fans are small and modern and they run more quietly and efficiently than ever before. You’ll find a great range of options, from classic fans that will get the job done to fans with fitted heat lamps, motion sensors and heat-exchanger ventilation that helps block warmed air from getting out through your ventilation. While you can find a lot of bells and whistles to pick from, the most imperative aspect of your fan is whether or not it’s full-sized 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 sufficient. 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 heed HGTV’s advice 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 proper size, or you know it’s the occasion for a new one, give the experts at McFadden Heating & Cooling at call at 1-866-781-0111. We’re here to help you guarantee you have a ventilation fan that will run hard to care for your home and keep it comfortable. You can even arrange an appointment with us online if that’s the most straightforward for you.