What Size Should My Bathroom Ventilation Fan Be?

Ordinary tasks like showering, bathing and shaving can put home-harming humidity into the air in your Manassas home. There’s good news however—a modest bathroom ventilation fan can protect you from distorted wood, mold growth, damaged 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? Air-Right Energy Design, Inc. is here to answer your questions.

Today’s bathroom ventilation fans are small and modern and they work more quietly and economically than ever before. You’ll find a great range of selections, from classic fans that will get the job done to fans with built-in heat lamps, motion sensors and heat-exchanger ventilation that helps block warmed air from getting out through your ventilation. While there are 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 exchange 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. So, if your bathroom is 5 feet by 8 feet, a CFM rating of 40 would be sufficient.

If you have a taller 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 straightforward, you can follow 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 right size, or you know it’s come to the point for a new one, give the experts at Air-Right Energy Design, Inc. at call at 703-260-1148. 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. 

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