What Size Should My Bathroom Ventilation Fan Be?

July 28, 2017

Ordinary tasks like showering, bathing and shaving can put home-harming humidity into the air in your Front Royal home. There’s good news still—a straightforward bathroom ventilation fan can save you from warped wood, mold growth, broken drywall and other problems related with a humid bathroom.

Even if you have ventilation fans in your bathrooms, do you know if they’re the right size? Are they as quiet and energy efficient as they could be? Dave's Diversified Services is here to answer your questions.

Today’s bathroom ventilation fans are small and smooth and they operate more quietly and efficiently than ever before. You’ll find a large 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 block warmed air from escaping through your ventilation. While you can find a lot of bells and whistles to select from, the most critical characteristic of your fan is whether or not it’s full-sized enough to do its job.

Assessed by the cubic feet per minute (CFM) of air they push, a bathroom ventilation fan should be able to exchange 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. Thus, 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 simple, you can heed HGTV’s guidance for bathrooms larger than 100 square feet – establish your CFM requirements by adding 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 Dave's Diversified Services at call at 540-636-3396. We’re here to help you guarantee you have a ventilation fan that will drive hard to guard your home and keep it comfy.