What Size Should My Bathroom Ventilation Fan Be?

Air Quality

Average tasks like showering, bathing and shaving can put home-harming humidity into the air in your Litchfield Park home. There’s good news though—a simple bathroom ventilation fan can save you from deformed wood, mold growth, cracked 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 correct size? Are they as soft and energy efficient as they could be? Cooler Tymes LLC is here to answer your questions.

Today’s bathroom ventilation fans are small and smooth and they operate more quietly and efficiently than ever before. You’ll find a large range of choices, from classic fans that will get the job done to fans with built-in heat lamps, motion sensors and heat-exchanger ventilation that helps avoid warmed air from getting out through your ventilation. While there are a lot of bells and whistles to select from, the most critical characteristic of your fan is whether or not it’s big enough to do its job.

Rated 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 typical 8-foot ceiling, your ventilation fan should have a CFM rating at least 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 satisfactory.

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 use 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 unsure if your bathroom ventilation fan is the right size, or you know it’s the occasion for a new one, give the pros at Cooler Tymes LLC at call at 623-208-6444. We’re here to help you make sure you have a ventilation fan that will run hard to care for your home and keep it cozy. 

Back To Blog