What Size Should My Bathroom Ventilation Fan Be?

Average tasks like showering, bathing and shaving can put home-harming humidity into the air in your Elmhurst home. There’s good news however—a simple bathroom ventilation fan can keep you from distorted wood, mold growth, cracked 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 correct size? Are they as soft and energy efficient as they could be? Alan Energy Services Air Conditioning and Heating Company is here to answer your questions.

Today’s bathroom ventilation fans are small and modern and they operate more quietly and economically than ever before. You’ll find a great range of selections, from average fans that will get the job done to fans with integrated heat lamps, motion sensors and heat-exchanger ventilation that helps prevent warmed air from getting out through your ventilation. While you can find a lot of bells and whistles to choose from, the most imperative aspect of your fan is whether or not it’s large enough to do its job.

Graded by the cubic feet per minute (CFM) of air they move, 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 at least as high as 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 larger 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 use HGTV’s advice for bathrooms larger than 100 square feet – verify your CFM requirements by increasing 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 the occasion for a new one, give the pros at Alan Energy Services Air Conditioning and Heating Company at call at 630-570-0252. We’re here to help you ensure you have a ventilation fan that will run hard to care for your home and keep it comfortable. 

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