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 Portland Metro home. There’s good news however—a straightforward bathroom ventilation fan can protect you from warped wood, mold growth, damaged drywall and other problems associated 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 quiet and energy efficient as they could be? Central Air Inc is here to answer your questions. Today’s bathroom ventilation fans are small and modern and they work more quietly and effectively than ever before. You’ll find a hefty 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 block warmed air from leaking through your ventilation. While you can find a lot of bells and whistles to select from, the most important aspect 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 transfer, 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 about 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 adequate. If you have a higher 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 heed HGTV’s guidance 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 Central Air Inc at call at 503-656-1908. We’re here to help you make sure you have a ventilation fan that will work hard to guard your home and keep it comfy. You can even set up an appointment with us online if that’s simplest for you.