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Window Condensation: Understanding What It Means

Window Condensation: Understanding What It Means

It’s almost that season where energy efficient windows can improve your heating bill by retaining more temperate air in your home while defending against the elements outside. However, you may start to find condensation settling on your windows and doors during colder months.

If you see condensation on your window, don’t panic! It isn’t time to start investigating 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. Instead, it means your windows are working well.

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

Do my new windows or doors create condensation?
Some homeowners pair the signs 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. Instead, it comes as a result of high humidity levels in your room.

As a matter of fact, the presence of condensation more often than not is a result of the improved energy efficiency of your new windows. Air with high 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 most likely the coldest part of the house, condensation shows up on windows initially, 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 warms, condensation begins to lessen.

More than a few factors go into whether you might find condensation on your windows. You might even discover that a window in one part of your room has roomside condensation while another in the same room doesn’t. Air circulation, changing room temperatures, air register location, and the type and size of the window can all influence the likelihood of roomside condensation. Other influnences such as glass type, window coverings and screens and proximity to a water source can all have an impact on what levels of humidity are around a window.

Why do I sometimes see condensation on opposite sides of the window?
Your previous windows could have been drafty or didn’t feature the advanced, energy efficient technology of today’s windows. Additionally, other home repairs, such as installing a new roof or siding, might also build a tighter seal against air infiltration in your room. As a result, your home may keep more humidity making condensation more likely to happen than before.

In the summer months, this same phenomenon can be seen on the outside of your windows. Exterior condensation can form as a result of 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 cools below the dew point of the outside air. Since the cooler air inside your home isn’t escaping due to increased energy efficiency, there’s a higher possibility to see external condensation at times like these.

You can deal with exterior condensation by opening shades at night to warm up exterior glass and promote air circulation by trimming any plants that might be obstructing windows. Adjusting the air conditioner a few degrees warmer can also make a difference.

For roomside condensation, there are a group of factors that can impact the humidity in your room. Here are some common culprits that can create roomside condensation:

Sources of humidity in your home 

The most frequent 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–up to four gallons or more per day in some homes. Add today’s energy efficient, well-insulated homes and you can start to see why that humidity can often find no path to escape.

As a result of this better insulation, some windows can develop 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 area where condensation on windows should become an immediate issue, however, is if condensation is seen 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 problem with your windows. It serves as an alert to the possibility of other hidden, potentially costly problems to be found in your house.

igh indoor humidity can result in structural damage and even upset your health. Because these effects frequently go without notice 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 grow into more serious concerns such as water stains on walls and ceilings if left alone.

In the same way, left unaddressed, condensation issues can mean window problems over time. Make sure to take continual roomside condensation seriously. Think of it as an early warning to high humidity in your room, one that can easily be dealt with before it gets worse. Understanding condensation is just the beginning to keeping your home cozy 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 Beltsville a call or visit the showroom.

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