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Window Condensation: Understanding What It Means

Window Condensation: Understanding What It Means

It’s almost that time of year where energy efficient windows can improve your heating expenses by keeping more temperate air in your house while resisting the elements outside. However, you may start to notice condensation gathering on your windows and doors during colder months.

If you notice condensation on your window, don’t panic! It isn’t time to start diagnosing your window. As a matter of fact, condensation on the inside of your windows—known as roomside condensation—isn’t a sign of a defective window at all. Rather, it means your windows are being efficient.

So, what is causing the condensation on your windows? And, more importantly, what signs of condensation should raise alarms about your window’s health? Here are the facts about window condensation:

Do my new windows or doors create condensation?
Some homeowners pair the presence of condensation in the months after installing new windows with potential problems during the installation process. Condensation on windows and doors is not created by the window or door product. Rather, it comes due to high humidity levels in your home.

As it turns out, the signs of condensation more often than not is a result of the better energy efficiency of your new windows. Air with increased humidity holds water vapor until it comes into contact with a surface temperature less than or equal to the dew point—the temperature at which air becomes saturated and produces dew. Since glass surfaces are usually the coldest part of the home, condensation shows up on windows initially, in the indication of water droplets or frost on the roomside of the house’s window. As the air inside grows drier, or as the glass surface becomes warmer, condensation begins to disappear.

Many factors go into whether you might see condensation on your windows. You might even discover that a window in one part of your room has roomside condensation while a different one doesn’t. Air circulation, varying room temperatures, air register location, and the type and size of the window can all increase the chances of roomside condensation. Other factors like glass type, window coverings and screens and proximity to a water source can all play a role in what levels of humidity are around a window.

Why do I occasionally see condensation on opposite sides of the window?
Your previous windows could have been drafty or didn’t have the advanced, energy efficient technology of modern windows. However, other home repairs, such as building a new roof or siding, might also establish a tighter seal against air infiltration in your home. Because of that, your home may keep more humidity making condensation more likely to be seen than before.

In the summer months, this same phenomenon can be seen on the outside of your windows. Exterior condensation can form due to high outdoor humidity, little or no wind, and a clear night sky. It grows in the same way as roomside condensation, when the temperature of the glass is cooled below the dew point of the outside air. Since the cooler air inside your home isn’t leaving due to increased energy efficiency, it’s more likely to see external condensation at these times.

You can deal with exterior condensation by opening curtains at night to warm up exterior glass and increase air circulation by removing any plants that might be interfering with windows. Adjusting the air conditioner a few degrees warmer can also help.

For roomside condensation, there are a few factors that can influence the humidity in your home. Here are a couple of common culprits that can lead to roomside condensation:

Sources of humidity in your home 

The most frequent way roomside humidity increases is through everyday activity. Running showers and baths, cooking and washing dishes, doing laundry, even the dog’s water bowl can all bring moisture to the air in your home–as much as four gallons or more per day in some homes. Include today’s energy efficient, well-insulated homes and you can start to see why that humidity can often find no way to escape.

Because of this better insulation, some windows can have a strip of condensation that shows up all the way around the roomside of the window. Normally, this happens when the center of the glass stays warmer than the glass closest to the edge. It isn’t an indication that the window is leaking air or not functioning correctly.

Can Roomside Condensation Damage My Windows?
One place where condensation on windows should become an immediate warning, however, is if condensation is noticed between the two sealed panes of insulating glass in multi-pane windows. In this case, condensation is a result of seal failure and the insulating glass will need to be replaced.

Most often though, condensation on your windows doesn’t mean there is a defect with your windows. It serves as an alert to the possibility of other unnoticed, potentially pricey problems elsewhere in your room.

igh indoor humidity can lead to structural damage and even affect your health. Because these effects frequently go unseen in the wall cavities, attics and crawl spaces, the visible indication of condensation on glass is a good sign that humidity levels are too high. And while window condensation and musty odors might be seen as bothersome, they can develop into more severe concerns such as water stains on walls and ceilings if left unresolved.

In the same way, left unaddressed, condensation issues can mean window problems over time. Make sure to take chronic roomside condensation seriously. Think of it as an early alarm to high humidity in your home, one that can easily be dealt with before it gets more severe. Understanding condensation is just the beginning to keeping your home comfy and maintaining your windows. If you have any questions about condensation and whether your windows and doors are working as they should, give Pella Windows and Doors in Mankato a call or stop by the showroom.

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