Why Do My Windows Sweat?

Humidity

• Humidity in the home can cause windows to sweat. Use a dehumidifier to help eliminate the moisture in the air, which can condense on the windows. Be sure to empty the water container regularly. Depending on how humid it is inside your home, you may have to empty the reservoir several times a day. If you use a humidifier and have a problem with sweating windows, you may be running it too much. Turn off the humidifier for a week or so and see if the problem corrects itself.

Temperature

• If the temperature in your home is warmer than the temperature of the glass, your windows will sweat. This is the same concept as pouring a glass of iced tea on a hot day. The glass will sweat because it is colder than the air around it. This can happen on very cold days when the outside temperature is much lower than the inside temperature. To remedy excessive window sweating, place a portable heater or some other heat source in front of the window to help heat up the glass.

Old Windows

• Older windows may have only single-pane glass which is more prone to sweating. Fix older windows by adding storm windows. New windows use thermal technology to prevent sweating. When purchasing new windows look for thermal insulated or double panes to help eliminate the problem of sweating glass.

Daily Activities

• Sometimes the normal routines of life can make your windows sweat. Anything you do that puts moisture into the air will cause your windows to sweat. You may notice that the windows sweat when you cook or take a hot shower, which sends steam and heat into the air. Adding vents to the kitchen and bathroom can help control this. Lowering your thermostat can also help with steaming windows.