What Size Should My Bathroom Ventilation Fan Be?

Air Quality

Average tasks like showering, bathing and shaving can put home-damaging humidity into the air in your Rock Hill home. There’s good news though—a modest bathroom ventilation fan can protect you from distorted wood, mold growth, cracked drywall and other problems related 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 quiet and energy efficient as they could be? US Air Heating and Cooling is here to answer your questions.

Today’s bathroom ventilation fans are small and sleek and they operate more quietly and effectively than ever before. You’ll find a large 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 block warmed air from leaking through your ventilation. While you have 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.

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 normal 8-foot ceiling, your ventilation fan should have a CFM rating at least as high as 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 satisfactory.

If you have a larger 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 simple, you can follow HGTV’s advice 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 proper size, or you know it’s the occasion for a new one, give the experts at US Air Heating and Cooling at call at 803-980-4328. We’re here to help you guarantee you have a ventilation fan that will drive hard to protect your home and keep it comfy. You can even set up an appointment with us online if that’s easiest for you.

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