What Size Should My Bathroom Ventilation Fan Be? 07/28/2017Average tasks like showering, bathing and shaving can put home-harming humidity into the air in your Bishop home. There’s good news still—a straightforward bathroom ventilation fan can keep you from warped wood, mold growth, broken drywall and other issues associated 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 soft and energy efficient as they could be? Bishop Heating & Air Conditioning is here to answer your questions. Today’s bathroom ventilation fans are small and sleek and they work more quietly and economically than ever before. You’ll find a great range of options, from simple 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 select from, the most important 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 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 almost 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 larger 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 use HGTV’s advice for bathrooms larger than 100 square feet – establish your CFM requirements by toting 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 Bishop Heating & Air Conditioning at call at 760-784-9034. We’re here to help you ensure 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.