What Size Should My Bathroom Ventilation Fan Be?

Ordinary tasks like showering, bathing and shaving can put home-damaging humidity into the air in your Lake Worth home. There’s good news still—a modest bathroom ventilation fan can protect you from deformed 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 proper size? Are they as soft and energy efficient as they could be? Smyth Air Conditioning Inc is here to answer your questions.

Today’s bathroom ventilation fans are small and sleek and they work 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 fitted heat lamps, motion sensors and heat-exchanger ventilation that helps block warmed air from getting out through your ventilation. While you have a lot of bells and whistles to select from, the most imperative characteristic of your fan is whether or not it’s big enough to do its job.

Assessed by the cubic feet per minute (CFM) of air they transfer, a bathroom ventilation fan should be able to replace 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 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 adequate.

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 easy, you can heed HGTV’s guidance 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 not sure if your bathroom ventilation fan is the correct size, or you know it’s come to the point for a new one, give the experts at Smyth Air Conditioning Inc at call at 561-533-6066 . We’re here to help you ensure you have a ventilation fan that will drive hard to protect your home and keep it cozy. 

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