What Size Should My Bathroom Ventilation Fan Be?

Everyday tasks like showering, bathing and shaving can put home-destructive humidity into the air in your Racine home. There’s good news though—a modest bathroom ventilation fan can keep you from deformed wood, mold growth, broken 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 quiet and energy efficient as they could be? Keystone Heating & Air Conditioning Co., Inc is here to answer your questions.

Today’s bathroom ventilation fans are small and smooth and they work more quietly and effectively than ever before. You’ll find a hefty range of choices, from simple 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 leaking through your ventilation. While you have a lot of bells and whistles to choose from, the most critical aspect of your fan is whether or not it’s full-sized enough to do its job.

Rated by the cubic feet per minute (CFM) of air they push, a bathroom ventilation fan should be able to replace 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 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 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 simple, you can heed HGTV’s guidance for bathrooms larger than 100 square feet – determine 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 not sure if your bathroom ventilation fan is the correct size, or you know it’s the occasion for a new one, give the professionals at Keystone Heating & Air Conditioning Co., Inc at call at 262-358-9468. We’re here to help you guarantee you have a ventilation fan that will work hard to protect your home and keep it comfy. 

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