What Size Should My Bathroom Ventilation Fan Be? 07/28/2017Ordinary tasks like showering, bathing and shaving can put home-damaging humidity into the air in your Paso Robles home. There’s good news though—a modest bathroom ventilation fan can save you from deformed wood, mold growth, broken drywall and other trouble related 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? Paso Robles Heating and Air is here to answer your questions. Today’s bathroom ventilation fans are small and modern and they run more quietly and efficiently than ever before. You’ll find a great range of choices, 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 you can find a lot of bells and whistles to pick from, the most critical characteristic of your fan is whether or not it’s large enough to do its job. Assessed by the cubic feet per minute (CFM) of air they move, 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 about 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 adequate. If you have a higher ceiling, the equation gets a little more complicated. 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 use HGTV’s guidance for bathrooms larger than 100 square feet – establish 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 not sure if your bathroom ventilation fan is the right size, or you know it’s time for a new one, give the professionals at Paso Robles Heating and Air at call at 805-238-7553. We’re here to help you make sure you have a ventilation fan that will run hard to guard your home and keep it cozy. You can even set up an appointment with us online if that’s the most straightforward for you.