What Size Should My Bathroom Ventilation Fan Be?

July 28, 2017

Everyday tasks like showering, bathing and shaving can put home-destructive humidity into the air in your Carson City home. There’s good news however—a modest bathroom ventilation fan can protect you from distorted wood, mold growth, broken 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 noiseless and energy efficient as they could be? Anderson Heating & A/C is here to answer your questions.

Today’s bathroom ventilation fans are small and sleek and they operate more quietly and effectively than ever before. You’ll find a large range of options, from average fans that will get the job done to fans with fitted heat lamps, motion sensors and heat-exchanger ventilation that helps avoid warmed air from getting out through your ventilation. While there are a lot of bells and whistles to choose from, the most imperative feature of your fan is whether or not it’s full-sized enough to do its job.

Graded by the cubic feet per minute (CFM) of air they push, a bathroom ventilation fan should be able to swap out 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 almost 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 straightforward, you can heed HGTV’s tips for bathrooms larger than 100 square feet – determine 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 proper size, or you know it’s time for a new one, give the experts at Anderson Heating & A/C at call at 775-230-7628. We’re here to help you make sure you have a ventilation fan that will work hard to protect your home and keep it cozy.