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 Omaha home. There’s good news however—a straightforward bathroom ventilation fan can protect you from warped 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? Interstate Heating & Air Conditioning is here to answer your questions.

Today’s bathroom ventilation fans are small and modern and they work more quietly and economically than ever before. You’ll find a hefty range of options, from simple 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 leaking through your ventilation. While you can find a lot of bells and whistles to pick from, the most important characteristic of your fan is whether or not it’s big enough to do its job.

Rated by the cubic feet per minute (CFM) of air they push, 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 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 adequate.

If you have a taller 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 straightforward, you can use 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 unsure if your bathroom ventilation fan is the right size, or you know it’s the occasion for a new one, give the experts at Interstate Heating & Air Conditioning at call at 402-509-5940. We’re here to help you guarantee you have a ventilation fan that will run hard to care for your home and keep it cozy.