What Size Should My Bathroom Ventilation Fan Be?

Average tasks like showering, bathing and shaving can put home-destructive humidity into the air in your West Jefferson home. There’s good news though—a simple bathroom ventilation fan can protect you from deformed wood, mold growth, cracked drywall and other issues 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? West Jefferson Plumbing and Heating, Inc. is here to answer your questions.

Today’s bathroom ventilation fans are small and smooth and they operate more quietly and effectively than ever before. You’ll find a large range of selections, from average 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 escaping through your ventilation. While there are 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.

Assessed by the cubic feet per minute (CFM) of air they move, a bathroom ventilation fan should be able to swap out 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 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 easy, 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 West Jefferson Plumbing and Heating, Inc. at call at 614-450-1575. We’re here to help you make sure you have a ventilation fan that will run hard to guard your home and keep it comfortable. 

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