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Why Is Your Window Sweating During Summer?

When summer starts, one of the first things people do is turn on their air conditioners. When you do, you’ll notice that your windows are fogging or sweating. Condensation in the warmer months is usually not a concern but in certain cases, it can be a sign that something is wrong with your windows. 

Read on to learn what causes your windows to become sweaty in the summer from a trusted provider of energy-efficient windows and doors.

Why Window Condensation Occurs

Condensation develops on windows when their surface is cooler than the outside air that touches it. It’s similar to when you pour ice-cold water into a glass and leave it outside. Your windows tend to sweat in the warmer months when the outside air is excessively humid and the inside temperatures remain relatively cool. It means that condensation in the summer is typically visual. 

Liquid water shouldn’t cause issues since the exterior of your window usually gets wet in the run. The fogging should subside as outside air temperatures rise. When the temperature inside is lower than the outside temperature, the Low-E coating in your windows will allow the glass outside to be even cooler. Given the right conditions, condensation can occur more on windows and patio doors with Low-E coatings. 

When Condensation Becomes a Problem

You should have your windows checked by a professional if the condensation stays on windows all day, even when the outside temperature has risen. Check if the moisture is forming and running down the walls. Discoloration, water stains, mold growth and peeling paint can indicate excessive moisture or humidity in your home. 

For energy-efficient and durable replacement windows, turn to Renewal by Andersen® of Montana. We also install high-quality French doors and sliding doors. Call us at (406) 206-2377 or fill out our contact form to get a free quote.


"I highly recommend Renewal by Andersen. We were treated well and everything went smoothly from start to finish. The company kept in contact with me before, during, and after the installation and let me know what to expect. I'm in love with my new windows! I will be using this company again when we refinish our basement. "

July, 21

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