Cold weather can make home improvement projects difficult. One common problem in the winter is condensation, or “sweating” windows. Condensation can make windows foggy, but it also has the potential to cause damage to your home. It’s best to take care of window condensation sooner rather than later.
What causes window condensation?
Interior condensation means water is present on the inside of the window. This usually happens during the colder months. Exterior condensation refers to water collection on the outside of the window, and this is most common during the summer. Both kinds have to do with humidity and a difference in temperature. (See our other blog, Controlling Moisture in Your Home for more information).
The winter season is also the heating season—especially in the Midwest—and warm air holds more moisture than cool air. When warm, humid air comes in contact with a cold window, the water vapor condenses to form droplets. This has to do with the dew point, which varies with temperature and humidity.
How to stop window condensation or “sweating” windows
The best way to stop window condensation is to reduce the amount of moisture in the air. Minimizing the difference between the temperature of the air and windows can also help.
Reduce humidifier use.
Although humidifiers are great for dryness caused by outdoor time in the winter, excessive use can raise indoor humidity levels quickly. If your windows are full of condensation, there is probably enough humidity in your home already.
Control steam produced by cooking.
Avoid producing steam with cooking as much as possible. Use lids over pots, and turn on the range hood especially when boiling water.
Promote air circulation.
Use fans to move air around. Opening windows for a brief amount of time can also be useful if the temperature allows for it. This allows some of the warm, humid air to escape outside quickly.
Keep windows warmer or lower the indoor air temperature.
If controlling humidity levels is not effective enough, try warming the windows or lowering the thermostat. (It’s best to pick one or the other for this option.) Windows can be kept warm with blinds, storm windows, weatherstripping, or increased air temperature. If you decide to increase air temperature, be aware of humidity levels. If both humidity and temperature rise, the problem will only worsen.
Check out our other related blog, Sealing Your Home for Winter.