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Why Do Windows “Sweat” During Summer?

By
austin pro
Written by Austin Pro Management
July 22, 2024

Are your windows frequently fogging up? Do you see moisture collecting on panes of glass as water droplets? This event is likely a case of condensation. In this post, Austin Pro Siding, Windows & Roofing — a local provider of window maintenance and siding repair services — discusses why windows form condensation in the summer months.

What Is Window Condensation?

Condensation occurs when warm, humid air comes into contact with colder surfaces. In the winter, when the heat is cranked up, it causes the humidity level indoors to increase. When the heated air comes into contact with cooler surfaces like windows, condensation takes place on their interior surfaces. Meanwhile, as the weather heats up outside during summer, the air inside your home becomes cooler. Water droplets, which appear like “sweating”, then form on the exterior surfaces of your windows.

Is Window Condensation Bad News?

While condensation on windows may look unsightly for some homeowners, it is not a reason to feel alarmed or think like your windows are not efficient at all. In fact, it is quite the opposite. According to window companies, condensation indicates that the airtight seals of your windows are doing their job. Weatherstripping, vapor barriers, insulation, and new installation techniques are a few other factors responsible for locking moisture inside your home, which drives up the chances of condensation.

The Purpose of Energy-Efficient Windows

Energy-efficient windows minimize unwanted heat transfer between the indoors and outdoors through the glass. They are commonly designed with low-E coatings which allow natural sunlight to flow into your home while deflecting ultraviolet and infrared light. This feature also keeps the exterior surface of the window at the same temperature as the air outside and the interior surface of the window at the same temperature as the air inside.

If your windows are not showing any sign of condensation during summer, it may be time to replace them. Austin Pro Siding, Windows & Roofing is one of the premier window replacement and vinyl siding contractors in Austin, TX. Our reliable team of professionals is committed to providing the comfort and efficiency that every homeowner is looking for in an exterior improvement project. Call us today at (512) 550-0000 or fill out our contact form to request a free, no-obligation quote.

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