What Size Should My Bathroom Ventilation Fan Be? 07/28/2017Everyday tasks like showering, bathing and shaving can put home-destructive humidity into the air in your McMurray home. There’s good news however—a simple bathroom ventilation fan can keep 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 right size? Are they as quiet and energy efficient as they could be? Kowalski Heating & Cooling is here to answer your questions. Today’s bathroom ventilation fans are small and sleek and they run more quietly and effectively than ever before. You’ll find a large range of choices, from classic 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 leaking through your ventilation. While there are a lot of bells and whistles to pick from, the most important characteristic 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 transfer, a bathroom ventilation fan should be able to exchange 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 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 sufficient. If you have a larger ceiling, the equation gets a little more difficult. 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 use HGTV’s guidance 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 not sure if your bathroom ventilation fan is the proper size, or you know it’s time for a new one, give the professionals at Kowalski Heating & Cooling at call at 724-745-7404. 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.