Condensation is the fog that suddenly appears in cold weather on the glass of windows and patio doors.It can block out the view, drip on the floor, freeze on the glass and be really annoying to homeowners.
While it seems natural to blame the windows, you shouldn’t. Window condensation is really an indication of excess humidity and moisture in your home. The glass simply provides a surface on which the moisture condenses visibly. The important thing to realize is that if excessive humidity is causing window condensation, it also be causing other problems – sometimes hidden problems – elsewhere in your home such as peeling paint, rotting wood, buckling floors, deteriorating insulation, mildew or moisture spots on your walls and ceilings.
We have an informational video by our friends at Andersen which explains where the condensation comes from and what you can do to prevent it.
Windows are typically the coolest areas of interior walls; even if they have storm panels, are glazed with welded insulating glass, have Low-E4® insulating glass or use triple-pane glass. When the warm, room temperature air comes in contact with the glass surface, the air is cooled and, if there is enough moisture in the air, the dew point will be reached and the water in the air will condense.
A good analogy is when you have an iced drink on a warm summer day, and the glass has moisture on the outside of it. The warmer air meeting the cooler surface of the glass causes condensation to form.
Recommended humidity levels in winter months should not exceed 30-35%. If these humidity levels are exceeded, you may want to take measures to reduce the interior humidity level.
Ways to Reduce Interior Humidity Level
- Checking your ventilation
- Using a dehumidifier
- Turning the humidifier on your furnace down (or off)
- Making sure blinds or curtains are open during the day
- Leaving ceiling fans on to promote air movement
- Use an exhaust fan in bathroom areas when showering
If these ideas do not resolve your concerns with indoor humidity, you may want to consult with a heating and air conditioning specialist. Additional information can be found in the Andersen Windows and Doors Guide to Understanding Condensation.