How To Keep Windows Condensation Free
The Window Wise National Certification Program sets minimum standards for windows and installation methods.
Over the past thirty years continual improvements have been made in insulating and air sealing homes. As a result, there are fewer air changes and an increased level of relative humidity inside our homes. During the winter, high humidity levels inside our homes often results in water condensing on the cold windowpane.
There are two methods of remedying this problem. Install new windows that are more energy efficient than your existing windows or reduce the relative humidity inside your house by increasing ventilation (allow dryer outside air to enter through a slightly opened window or install a heat recovery ventilation unit.)
|
Glazing Type |
Condensation Resistance |
|
Double Glass |
26% |
|
Double Glass, with Low E and Argon Gas |
40% |
Warm the glazing: better quality windows have a better R rating and better condensation resistance. The chart above compares a standard double glazed window with a higher quality window that has an insul-glass unit with Low E and Inert Gas.
Lower The Humidity:
|
Outdoor Temperature
|
Relative Humidity with
Standard Window |
Relative Humidity with
Energy Efficient Window |
|
0 C |
50% |
63% |
|
-10C |
38% |
50% |
|
-15C |
32% |
45% |
|
-20C |
26% |
40% |
Lower the Relative Humidity: Cooking, washing and bathing are the major sources of water vapour in our homes. Reducing these activities will lower relative humidity. However, if this is not possible then exhausting humid inside air and replacing it with drier outside air is the only option.
|