What Size Should My Bathroom Ventilation Fan Be? 07/28/2017Ordinary tasks like showering, bathing and shaving can put home-destructive humidity into the air in your Aurora home. There’s good news however—a simple bathroom ventilation fan can save you from warped wood, mold growth, cracked drywall and other trouble related 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? Service Plus Mechanical is here to answer your questions. Today’s bathroom ventilation fans are small and modern and they operate more quietly and economically than ever before. You’ll find a great range of selections, from simple 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 getting out through your ventilation. While you can find a lot of bells and whistles to choose from, the most critical aspect of your fan is whether or not it’s big enough to do its job. Assessed by the cubic feet per minute (CFM) of air they push, a bathroom ventilation fan should be able to replace 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 about 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 satisfactory. If you have a taller 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 use HGTV’s tips for bathrooms larger than 100 square feet – establish your CFM requirements by increasing 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 proper size, or you know it’s come to the point for a new one, give the professionals at Service Plus Mechanical at call at 630-473-4749. 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 set up an appointment with us online if that’s easiest for you.