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Why Is There Moisture on Inside of Windows?

Home with new siding and an American flag

So, you finally replaced your old, inefficient windows, only to discover moisture sitting inside them. What gives? Did you spend that money to replace them all for nothing? Good news: moisture on inside of windows is not uncommon.

And, best of all, it’s not difficult to remedy the situation. Continue reading to learn more about what causes moisture inside window panes to form and what you can do to prevent it from happening in the future. 

Why Is There Moisture on the Inside of My Windows?

Window Condensation, in general, forms when it is cold outside and the humidity level in your home is too high. During very cold weather, like the kind we get here in the Chicago area, you need to decrease the humidity levels in your home to avoid condensation build-up. 

Is Condensation Inside Windows Normal?

Yes! Condensation tends to form on colder surfaces around your home. Since your windows are closer to the outside than other areas of your home, it’s not uncommon for condensation to form when the humidity levels in your home are too high. Then, when the temperature in the outside air rises, the condensation goes away.

What Causes Moisture Inside Windows?

It’s important to remember that condensation on your windows is not an issue of leaking or water damage. It’s simply a combination of air temperature and humidity levels that lead to condensation. 

So, why is this happening on your new windows when it didn’t happen on your old ones? Your inefficient windows allowed the warm air from inside your home to reach the outside glass, so any condensation that did form dissipated quickly. 

Since your new windows are more energy efficient, they prevent the warm inside air from reaching the outside pane, so condensation forms when humidity levels are high inside. 

Can Moisture in Windows Be Fixed?

Absolutely! The key is to reduce the humidity levels in your home. As a good rule of thumb, when the outside temperature is above 20°F, humidity levels in your home should be between 30% and 35%. From there, the lower the outside temperature is, the lower your inside humidity levels should be. 

For example, if the temperature is -10°F, your indoor humidity levels should be between 15% and 20%.

How to Stop Moisture in Windows

Now that you know you need to lower humidity levels inside your home to get rid of moisture on your windows, here are a few steps to follow to do so:

  • Air out your home by opening your windows for a few minutes each day to let moist air escape
  • Be careful not to overwater houseplants, which can increase humidity levels
  • If you use a humidifier, check the settings to make sure you have the right levels in your home
  • Use ventilation during activities that produce humidity, like using your bathroom fan when taking a shower

Here for All Your Exterior Needs

We hope after reading this guide, you have peace of mind that moisture on the inside of your windows is no cause for concern. If you haven’t updated your windows to be energy-efficient yet, you’re likely noticing much more serious issues than condensation.

Our team of professionals can help you with condensation resources as well as installing these window types in the chicagoland area:

Our team is here to talk to you about your replacement options so your whole home can be more efficient. Contact us today to set up a free consultation.

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