What Size Should My Bathroom Ventilation Fan Be? 07/28/2017Average tasks like showering, bathing and shaving can put home-damaging humidity into the air in your Selbyville home. There’s good news though—a modest bathroom ventilation fan can keep 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 proper size? Are they as soft and energy efficient as they could be? Red Dog Cooling, Heating, & Plumbing is here to answer your questions. Today’s bathroom ventilation fans are small and sleek and they operate more quietly and efficiently than ever before. You’ll find a hefty range of selections, from classic fans that will get the job done to fans with built-in heat lamps, motion sensors and heat-exchanger ventilation that helps avoid warmed air from escaping through your ventilation. While there are a lot of bells and whistles to choose from, the most imperative characteristic of your fan is whether or not it’s full-sized enough to do its job. Rated by the cubic feet per minute (CFM) of air they move, a bathroom ventilation fan should be able to exchange 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 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 sufficient. 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 heed HGTV’s guidance for bathrooms larger than 100 square feet – determine 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 correct size, or you know it’s the occasion for a new one, give the professionals at Red Dog Cooling, Heating, & Plumbing at call at 302-436-2922. We’re here to help you make sure you have a ventilation fan that will drive hard to guard your home and keep it comfy. You can even set up an appointment with us online if that’s the most straightforward for you.