What Size Should My Bathroom Ventilation Fan Be?

July 28, 2017

Ordinary tasks like showering, bathing and shaving can put home-damaging humidity into the air in your Huntsville home. There’s good news though—a simple bathroom ventilation fan can protect you from warped wood, mold growth, broken drywall and other issues 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 noiseless and energy efficient as they could be? All Weather Heating & Air Conditioning Inc is here to answer your questions.

Today’s bathroom ventilation fans are small and smooth and they work more quietly and efficiently than ever before. You’ll find a great range of choices, from simple fans that will get the job done to fans with built-in heat lamps, motion sensors and heat-exchanger ventilation that helps block warmed air from escaping through your ventilation. While you have a lot of bells and whistles to choose from, the most critical 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 transfer, 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 almost as high as the number of square feet in your bathroom. So, if your bathroom is 5 feet by 8 feet, a CFM rating of 40 would be adequate.

If you have a higher 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 straightforward, you can heed HGTV’s guidance for bathrooms larger than 100 square feet – establish 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 unsure 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 All Weather Heating & Air Conditioning Inc at call at 256-801-4701. We’re here to help you ensure you have a ventilation fan that will work hard to protect your home and keep it comfortable.