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Why Are My Windows Fogging Up?

Foggy windows can be anything from a source of mild annoyance to a cause for alarm, particularly the latter if fogging happens during certain seasons. In today’s post, replacement window company Renewal by Andersen® of Kansas City takes a look at the causes of foggy windows and whether or not you should be worried.

Windows Fogging

What Causes Window Fogging?

The fog on your windows is fine condensation, which is what happens when humidity or moisture in the air collects on a surface that’s cooler than the air surrounding it. It’s the same as the condensation that collects on the surface of a cold glass of water, or your eyeglasses fogging up when you step out of a cold room.

It’s important to note that foggy windows are not a cause for alarm. In fact, it indicates that your window seals are working. During the winter season, you’re more likely to find condensation on the indoor surface of the windows because outdoor temperatures would be lower. You’d probably be running a humidifier to make up for the dry winter air. The reverse is true during the summer season: the outdoor surface would be foggy because of the high humidity levels, and that the indoor space would be cooled by your air conditioner.

Fogging Between Window Panels

If you have windows with insulated glass, then there is one type of fogging that you should keep an eye out for — when it occurs between the glass panels. Insulated glass consists of two glass panels with a sealed airspace between, which serves as an insulating layer. If the seal between the glass panes is broken, moisture would penetrate this space, resulting in fogging or condensation.

What Should You Do?

Persistent fogging can be fixed by simply adjusting your HVAC system’s settings. If the windows are getting too much cold air blown in their direction, adjust your air conditioner fan’s settings so they’re not fixed in just one position. During the winter season, check your relative indoor humidity levels. If they’re higher than 50%, reduce your humidifier’s output.

The broken seals on insulated glass can be fixed, depending on several factors. Some warranties have coverage for window seals; others don’t. Some window sashes are repairable, while others may require a completely new sash. Regardless of cause, it’s always best to ask your window replacement contractor first for advice.

Renewal by Andersen of Kansas City is one of the most trusted replacement window companies serving communities in Kansas City, MO. Give us a call at (913) 956-0887 or fill out our contact form to schedule an appointment.

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"I highly recommend Renewal by Andersen. I am extremely impressed with their ability to take care of any issues I have. The product is superb and is the first thing everyone notices when they come to my home."

April, 7

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