What Size Should My Bathroom Ventilation Fan Be?

Air Quality

Everyday tasks like showering, bathing and shaving can put home-destructive humidity into the air in your Winchester home. There’s good news still—a straightforward bathroom ventilation fan can save you from warped wood, mold growth, damaged 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 proper size? Are they as quiet and energy efficient as they could be? Thornberry Bros Inc is here to answer your questions.

Today’s bathroom ventilation fans are small and sleek and they operate more quietly and economically than ever before. You’ll find a great 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 block warmed air from getting out through your ventilation. While you can find a lot of bells and whistles to choose from, the most important characteristic 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 standard 8-foot ceiling, your ventilation fan should have a CFM rating about 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 sufficient.

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 straightforward, you can follow HGTV’s advice 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 time for a new one, give the pros at Thornberry Bros Inc at call at 859-745-1564. We’re here to help you make sure you have a ventilation fan that will run hard to guard your home and keep it cozy. 

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