What Size Should My Bathroom Ventilation Fan Be?

Air Quality

Everyday tasks like showering, bathing and shaving can put home-damaging humidity into the air in your Excelsior Springs home. There’s good news however—a straightforward bathroom ventilation fan can keep you from deformed wood, mold growth, cracked drywall and other trouble associated 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? Colvin's Inc is here to answer your questions.

Today’s bathroom ventilation fans are small and modern and they run 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 built-in heat lamps, motion sensors and heat-exchanger ventilation that helps avoid warmed air from escaping through your ventilation. While you have a lot of bells and whistles to select from, the most important feature of your fan is whether or not it’s large 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 swap out the air in a bathroom at least eight times an hour. With a standard 8-foot ceiling, your ventilation fan should have a CFM rating at least 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 satisfactory.

If you have a higher 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 straightforward, you can use HGTV’s guidance for bathrooms larger than 100 square feet – determine 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 unclear if your bathroom ventilation fan is the correct size, or you know it’s time for a new one, give the pros at Colvin's Inc at call at 816-630-2702. We’re here to help you ensure you have a ventilation fan that will work hard to care for your home and keep it comfy. 

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