If you often see water beading on the ceiling of your bathroom, you may have a condensation problem that can turn into a health concern for you and your family. The water causes wallpaper and paint to peel -- but worse, it promotes mold growth, a respiratory hazard. You're more likely to have a condensation problem if you live in a cool, damp climate or if your bathroom doesn't have enough ventilation.
Causes of Condensation
Condensation forms when warm, moist air contacts a cold surface. The sudden change in temperature cause water vapor to condense, and the condensation collects on the surface in the form of droplets. In a bathroom, the coldest surfaces are usually the porcelain or metal ones, so you'll probably notice condensation on the toilet, sink and faucets first. If the bathroom is under-heated, or it doesn't have enough insulation, the condensation will eventually form on the walls and ceiling and floor. Lack of ventilation contributes to the problem, because the air doesn't dry out quickly, and the water droplets can't evaporate.
Tackling Temperature Differences
Temperature differences cause condensation, and you can reduce that condensation by making those differences smaller. One way to do that is to turn up the heat in the bathroom. If adjusting the central heating thermostat a few degrees higher is impractical, you could bring a space heater into the bathroom and run it when the shower is in use, as well as for an hour or two afterward. Another strategy that actually saves energy instead of requiring you to use more is to turn the bath and shower temperature down a little and to take shorter showers.
If your bathroom is well ventilated, it may not matter whether or not there's a temperature differential, because the circulating air promotes evaporation. If you have an exhaust fan, turn it on whenever anyone is using the shower and until all the steam has cleared off the mirrors. If you don't have a fan, open the windows as soon as you can after getting out of the shower. If your bathroom doesn't have adequate ventilation, you may have to plug a portable fan into the bathroom outlet and leave the door ajar. Hang a sign on the door that advises people that the bathroom is in use.
Hanging wet towels in the bathroom increases the moisture in the air, so take them outside to dry. You can also reduce ambient moisture by fixing faucet leaks. If you live in a cool, damp climate, condensation may be a problem no matter what you do. If so, paint the walls with anti-condensation paint. It is formulated to absorb some of the moisture from condensation and release it back into the air over a period of time. It isn't a solution for condensation, but using it will reduce the possibility of mold and peeling.