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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 impact your heating expenses by keeping more temperate air in your home while resisting 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. In fact, condensation on the inside of your windows—known as roomside condensation—isn’t a sign of a defective window at all. Just the opposite, it means your windows are doing their job.

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

Do my new windows or doors cause condensation?
Some homeowners connect the sight of condensation in the months after installing new windows with unnoticed problems during the installation process. Condensation on windows and doors is not created by the window or door product. Actually, it comes because of high humidity levels in your house.

In reality, the sight of condensation more often than not is an indication of the better energy efficiency of your new windows. Air with high humidity holds water vapor until it touches a surface temperature less than or equal to the dew point—the temperature at which air becomes saturated and produces dew. Because glass surfaces are usually the coldest part of the house, condensation appears on windows initially, in the form of water droplets or frost on the roomside of your window. As the air inside grows drier, or as the glass surface warms, condensation begins to disappear.

Numerous 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 impact the presence of roomside condensation. Other influnences such as 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 at times see condensation on opposite sides of the window?
Your previous windows may have been drafty or didn’t include the advanced, energy efficient elements of today’s windows. But, other home repairs, such as adding a new roof or siding, might also establish a tighter seal against air infiltration in your home. As a result, your home may hold more humidity making condensation more frequentl than before.

In the warmer seasons, this same phenomenon can be observed on the outside of your windows. Exterior condensation can gather because 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 drops below the dew point of the outside air. Since the cooler air inside your room isn’t leaving due to increased energy efficiency, there’s a higher possibility to see external condensation in these situations.

You can manage exterior condensation by opening curtains at night to warm up exterior glass and increase air circulation by trimming any plants that might be blocking windows. Setting the air conditioner a few degrees warmer can also help.

For roomside condensation, there are a number of factors that can impact the humidity in your home. Here are some common culprits that can cause roomside condensation:

Sources of humidity in your home 

The most frequent way roomside humidity increases is through everyday living. Heat and moisture from 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. Factor in today’s energy efficient, well-insulated homes and you can start to see why that humidity can often find no path to escape.

Due to this better insulation, some windows can develop a strip of condensation that forms 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 an indication that the window is leaking air or not functioning correctly.

Can Roomside Condensation Damage My Windows?
One area where condensation on windows should become an immediate concern, however, is if condensation is appearing between the two sealed panes of insulating glass in multi-pane windows. In this case, condensation is a sign of seal failure and the insulating glass must 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 unseen, potentially costly problems to be found in your room.

High indoor humidity can eventually cause structural damage and even affect 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 bothersome, they can grow into more severe concerns such as water stains on walls and ceilings if left unresolved.

In the same way, left unaddressed, condensation issues can lead to window problems over time. Make sure to take continual roomside condensation seriously. Think of it as an early alarm to high humidity in your room, one that can easily be solved before it gets serious. 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 effectively, give Pella Windows and Doors in Terre Haute a call or visit the showroom.

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