Window Energy Efficiency: Condensation Resistance

Window Energy Efficiency: Condensation Resistance

by | Oct 9, 2020 | Energy Efficiency, Types of Windows | 0 comments

If you’ve ever had a cold drink outside during the summer, you know the familiar feeling of your glass “sweating” in your hand. Of course, the moisture isn’t coming from a crack in your glass. Moisture in the warm, humid air is making contact with your cold drink and depositing droplets onto the outside of your glass in a process known as condensation. That is the same process that can cause water to condense on the inside or outside of a window!

In the right circumstances, any window can have condensation appear on the surface of the glass, especially during those warm, humid months here in Houston. However, all modern windows are designed with special materials that resist the forming of condensation under all but the most extreme situations. Here’s a closer look at window condensation and how you can avoid it.

Have you noticed water droplets running down the outside glass of your window? It’s not leaking, just allowing condensation to form. Here’s how to stop that from happening. #CustomWindowsTX Click To Tweet

What Causes Condensation?

Two primary factors play a large role in condensation in climates like ours: the warmth and humidity of the outside air and the temperature of your window panes. If humidity is high and the glass temperature is low, water vapor in the air begins to try to cling to the glass and turn back into liquid.

Water vapor requires cooler temperatures in order to condense, however, so these liquid deposits occur on the coldest available object, whether that is the surface of a glass of ice water or a cold windowpane. This can be particularly true if there is a rapid temperature change outside or your air conditioning is blowing right on your windows.

Improving Condensation Resistance

Modern dual pane windows are dramatically better at resisting condensation than older single pane and even older dual pane windows. The dual-pane insulated glass helps, but so does the improved materials such as thermal breaks used in aluminum, vinyl with air channels designed to balance the energy flow, or very inert designs such as clad wood windows.

Also, the newest warm-edge spacers and argon are used to construct the dual-pane glass units and definitely help reduce condensation. (To double-check how much a window will resist condensation forming, check out the window condensation resistance factor tool from the AAMA.)

Pro Tip: Condensation can occur on the best windows and it shouldn’t be confused with a seal failure. If you are not sure, wait for a few hours! Exterior condensation will dissipate over time as temperatures equalize, where a true seal failure with condensation between the glass panes will stay and not dissipate for days.

Other Ways to Avoid Condensation

Nobody likes dealing with water clinging to their windows even if it is only temporary. You can check a few additional things that may help reduce the chances of condensation further, such as making sure that your air conditioning isn’t blowing directly on your windows. Also, trim outside bushes so that they are not right next to your windows since the bushes tend to be additional sources of humidity!

Contact us to learn more about keeping water away from your windows’ interiors.