Anyway, the fogged-up mirror got my humidity clogged brain thinking about exhaust fans in bathrooms and how important they really are. Yep…I’m always thinking about work.
So, why is it important that we have some sort of ventilation in our bathrooms?
The first thing that comes to mind is to remove unwanted and unpleasant odors due to, well, bathroom activities. Come on admit it…that’s what you were thinking and you’re partly correct.
Perhaps even worse than unpleasant odors in your bathroom is a build-up of unwanted steam. Without ventilation in your bathroom condensation can form on just about every surface in the bathroom causing paint to streak, mold to grow, wallpaper to peal, wood to rot, and even cause structural issues with the framing members that surround your bathroom.
Older homes often lack bathroom exhaust fans because in the good ‘ol days if the bathroom was smelly or steamy the architects and builders thought you could open a window. Seriously? Maybe if the weather is perfect but on days where temperatures are freezing or hot this isn’t a very logical ventilation method.
Experts agree that the best way to ventilate a bathroom is an exhaust fan. Exhaust fans should be at least 50 CFM (cubic feet per minute) and go up from there depending on the size of the bathroom and be vented straight to the exterior of your home (not into the attic as that can cause all sorts of mold issues too). Ideally the maximum duct length should be 10 feet or less – 20 feet if you must – with no more than a few elbows (each elbow has the equivalent resistance of 15 feet of smooth metal duct). Smooth-wall duct is preferable to flexible (ribbed) duct. If you must use the flexible (ribbed) duct it will increase the static pressure of the system so a more powerful fan will need to be used.
We recommend operating your exhaust fan for at least 15 minutes after finishing your bath or shower. This will help more the humid air out of the bathroom. We also recommend installing a digital or analog timer switch to control the exhaust fan (where applicable) which will automatically turn off the exhaust fan after a predetermined amount of time.
Do you already have an exhaust fan but suspect it’s not working? The simplest way to test your fan’s suction is to take a single square of toilet paper and place it along the fan vent while the fan is running. If the fan holds up the toilet paper then it’s working properly.
What did we learn?
- excessive humidity in your bathroom is bad
- If you don’t have exhaust fans in your bathrooms – get them and make sure they are vented directly to the exterior of your home
- If you have existing exhaust fans test them using the toilet paper method
- Consider installing a digital or analog timer to control the fan so it can continue to operate at least 15 minutes following the end of your bath or shower.