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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 holding more temperate air in your home while defending against the elements outside. However, you may start to see condensation gathering on your windows and doors during colder months.

If you find condensation on your window, don’t stress! 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 doing their job.

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 cause condensation?
Some homeowners associate the sight of condensation in the months after installing new windows with potential problems during the installation process. Condensation on windows and doors is not caused by the window or door product. Actually, it comes as a result of high humidity levels in your house.

In reality, the sight of condensation more often than not is a result of the improved energy efficiency of your new windows. Air with increased humidity keeps 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 often the coldest part of the house, condensation can be seen on windows first, in the presence of water droplets or frost on the roomside of your window. As the air inside gets drier, or as the glass surface heats up, condensation begins to disappear.

Numerous factors go into whether you might see condensation on your windows. You might even notice 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 presence 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 can be noticed around a window.

Why do I sometimes see condensation on opposite sides of the window?
Your previous windows may have been drafty or didn’t include the advanced, energy efficient components of present-day windows. But, other home repairs, such as installing a new roof or siding, might also establish a tighter seal against air infiltration in your room. Because of that, your home may hold more humidity making condensation more likely to be seen than before.

In the heat, this same phenomenon can be noticed on the outside of your windows. Exterior condensation can form because of high outdoor humidity, little or no wind, and a clear night sky. It forms 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 leaking due to increased energy efficiency, there’s a greater chance to see external condensation in these situations.

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

For roomside condensation, there are a few factors that can determine the humidity in your house. Here are a few common culprits that can cause roomside condensation:

Sources of humidity in your home 

The most common way roomside humidity increases is through everyday living. Running showers and baths, cooking and washing dishes, doing laundry, even the dog’s water bowl can all add 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 understand why that humidity can often find no way to escape.

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

Can Roomside Condensation Hurt My Windows?
One place where condensation on windows should become an immediate issue, however, is if condensation is appearing between the two sealed panes of insulating glass in multi-pane windows. In this case, condensation is a mark of seal failure and the insulating glass should be replaced.

More often than not though, condensation on your windows doesn’t mean there is a defect with your windows. It serves as an indicator to the possibility of other unseen, potentially expensive problems to be found in your home.

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

In the same way, left unaddressed, condensation issues can lead to window problems over time. Make sure to take reoccurring roomside condensation seriously. Think of it as an early alarm to high humidity in your room, one that can easily be resolved before it gets serious. 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 resisting condensation properly, give Pella Windows and Doors in Peoria a call or come into the showroom.

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