What Size Should My Bathroom Ventilation Fan Be?

July 28, 2017

Average tasks like showering, bathing and shaving can put home-destructive humidity into the air in your Macon home. There’s good news though—a straightforward bathroom ventilation fan can save you from warped 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 noiseless and energy efficient as they could be? Air Temperature Control 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 hefty 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 avoid warmed air from getting out through your ventilation. While you can find a lot of bells and whistles to select from, the most critical feature of your fan is whether or not it’s large enough to do its job.

Graded by the cubic feet per minute (CFM) of air they move, a bathroom ventilation fan should be able to swap out 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. Thus, if your bathroom is 5 feet by 8 feet, a CFM rating of 40 would be adequate.

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 follow HGTV’s guidance 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 correct size, or you know it’s come to the point for a new one, give the professionals at Air Temperature Control at call at 478-202-3170. We’re here to help you guarantee you have a ventilation fan that will work hard to care for your home and keep it comfy.