What Size Should My Bathroom Ventilation Fan Be? 07/28/2017Ordinary tasks like showering, bathing and shaving can put home-harming humidity into the air in your Carpentersville home. There’s good news however—a simple bathroom ventilation fan can save you from distorted wood, mold growth, cracked 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? Controlled Comfort HVAC Inc 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 integrated 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 select from, the most imperative characteristic of your fan is whether or not it’s large 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 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. So, 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 follow HGTV’s advice 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 unclear if your bathroom ventilation fan is the correct size, or you know it’s time for a new one, give the pros at Controlled Comfort HVAC Inc at call at 224-699-9229. 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. You can even schedule an appointment with us online if that’s simplest for you.