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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 affect your heating costs by keeping 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 see condensation on your window, don’t worry! 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. Rather, it means your windows are being efficient.

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

Do my new windows or doors lead to condensation?
Some homeowners connect the sight of condensation in the months after installing new windows with possible problems during the installation process. Condensation on windows and doors is not produced by the window or door product. Actually, it comes due to high humidity levels in your room.

In reality, the presence of condensation more often than not is an indication of the better energy efficiency of your new windows. Air with increased humidity retains 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 often the coldest part of the home, condensation shows up on windows initially, in the presence of water droplets or frost on the roomside of the window. As the air inside becomes drier, or as the glass surface heats up, condensation begins to lessen.

Numerous factors go into whether you might notice 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, changes in 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 determine what levels of humidity are around a window.

Why do I occasionally see condensation on opposite sides of the window?
Your previous windows might have been drafty or didn’t include the advanced, energy efficient elements of modern windows. However, other home repairs, such as adding a new roof or siding, might also create a tighter seal against air infiltration in your home. 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 observed 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 escaping due to increased energy efficiency, it’s more likely to see external condensation in these situations.

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 obstructing windows. Adjusting 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 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 increase 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 means of escape.

Due to this better insulation, some windows can build a strip of condensation that forms all the way around the roomside of the window. Most often, this happens 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 Ruin My Windows?
One place where condensation on windows should become an immediate concern, however, is if condensation is seen between the two sealed panes of insulating glass in multi-pane windows. In this instance, condensation is a result of seal failure and the insulating glass should be replaced.

Most often though, condensation on your windows doesn’t mean there is a problem with your windows. It serves as a sign to the possibility of other hidden, potentially pricey problems to be found in your room.

igh indoor humidity can lead to structural damage and even affect your health. Because these effects frequently go unnoticed in the wall cavities, attics and crawl spaces, the visible presence 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 nuisances, 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 cause window problems over time. Make sure to take reoccurring roomside condensation seriously. Think of it as an early warning to high humidity in your house, one that can easily be resolved 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 doing their jobs effectively, give Pella Windows and Doors in Ketchum a call or stop by the showroom.

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