What Size Should My Bathroom Ventilation Fan Be?

Ordinary tasks like showering, bathing and shaving can put home-harming humidity into the air in your Brighton home. There’s good news however—a modest bathroom ventilation fan can keep you from distorted wood, mold growth, cracked 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 correct size? Are they as soft and energy efficient as they could be? D & D Heating & AC is here to answer your questions.

Today’s bathroom ventilation fans are small and sleek and they run more quietly and efficiently than ever before. You’ll find a hefty range of choices, from classic 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 have a lot of bells and whistles to choose from, the most imperative 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 move, a bathroom ventilation fan should be able to replace 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 at least as high as the number of square feet in your bathroom. Thus, if your bathroom is 5 feet by 8 feet, a CFM rating of 40 would be satisfactory.

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 follow HGTV’s guidance for bathrooms larger than 100 square feet – verify 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 unsure if your bathroom ventilation fan is the proper size, or you know it’s come to the point for a new one, give the professionals at D & D Heating & AC at call at 720-316-1401. We’re here to help you guarantee you have a ventilation fan that will run hard to care for your home and keep it comfortable. 

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