Condensation on windows can be a worrisome sight, but should you be alarmed if you see it on your windows? Here’s why windows “sweat” during the warm seasons and why it’s not as big a problem as it looks.

Why Do Windows “Sweat”?

The “sweat” on window glass is condensation that is formed when moisture in the air comes in contact with a relatively cooler surface. For example, the moisture on the surface of a glass of cold water doesn’t come from the contents of the glass. Rather, moisture in the air collects on the glass surface because the glass is cooler than the air. The same thing happens when you’re wearing eyeglasses and you leave a cold room – the lenses become foggy because it’s cooler than the surrounding air.

Is Condensation Bad for Your Windows?

Condensation forms on window surfaces for the same reason. During winter, condensation can be more pronounced because the glass surface would be cooler than the heated and humidified indoor space. The good news is it’s not something you should be worried about: it only means that the seals around your windows are working perfectly, and there would be no need to arrange for window installation because of it.

During the warm seasons, windows can “sweat” on the outside surface, especially after sundown when outdoor temperatures drop. Again, this is not a cause for concern. It just means that outdoor humidity has cooled enough that it doesn’t immediately evaporate when it comes into contact with your windows.

Condensation Between Glass Panels

There is one kind of window condensation that you should watch out for if you have insulated windows. A standard insulated glass consists of two or three glass panels, which are intended to separate the indoor and outdoor surfaces to reduce thermal transfer. The airspace between these glass panels are sealed, and if the seal breaks, air and moisture can infiltrate this. This means if you find condensation between the glass panels, you may need to have your windows repaired or replaced.

Renewal by Andersen® of San Diego is the leading replacement window contractor serving customers in San Diego, CA, and the surrounding communities. Give us a call at (858) 935-8451, or fill out our contact form to schedule an appointment.