What Size Should My Bathroom Ventilation Fan Be?

Ordinary tasks like showering, bathing and shaving can put home-destructive humidity into the air in your Buellton home. There’s good news however—a straightforward bathroom ventilation fan can save you from distorted wood, mold growth, cracked drywall and other trouble connected 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? Allstar Heating & Air Conditioning is here to answer your questions.

Today’s bathroom ventilation fans are small and smooth and they work more quietly and effectively than ever before. You’ll find a great range of selections, 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 there are a lot of bells and whistles to select from, the most imperative feature 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 swap out 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. So, if your bathroom is 5 feet by 8 feet, a CFM rating of 40 would be sufficient.

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 heed HGTV’s tips 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 right size, or you know it’s come to the point for a new one, give the experts at Allstar Heating & Air Conditioning at call at 805-242-9638. We’re here to help you ensure you have a ventilation fan that will work hard to care for your home and keep it comfy. 

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