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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 keeping more temperate air in your house while resisting the elements outside. However, you may start to find 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 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 being efficient.

So, what is creating the condensation on your windows? And, more importantly, what types 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 signs of condensation in the months after installing new windows with potential problems during the installation process. Condensation on windows and doors is not produced by the window or door product. Instead, it comes as a result of high humidity levels in your house.

In reality, the signs of condensation more often than not is an outcome of the increased energy efficiency of your new windows. Air with more 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. Due to the fact that glass surfaces are often the coldest part of the home, condensation shows up on windows initially, in the form 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.

Many 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 one on the other side doesn’t. Air circulation, changing room temperatures, air register location, and the type and size of the window can all influence the chances of roomside condensation. Even the glass type, window coverings and screens and proximity to a water source can all have an impact on 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 feature the advanced, energy efficient technology of today’s windows. But, other home repairs, such as installing a new roof or siding, might also create a tighter seal against air infiltration in your home. Because of that, your home may keep more humidity making condensation more frequentl than before.

In the heat, this same phenomenon can be observed on the outside of your windows. Exterior condensation can gather as a result 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 drops below the dew point of the outside air. Since the cooler air inside your room isn’t escaping due to increased energy efficiency, it’s more likely to see external condensation at these times.

You can manage exterior condensation by opening shades at night to warm up exterior glass and promote air circulation by cutting back any bushes that might be obstructing windows. Programming the air conditioner a few degrees warmer can also make a difference.

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

Sources of humidity in your home 

The most commonly seen way roomside humidity increases is through everyday home activities. 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 get an idea why that humidity can often find no way to escape.

As a result of this better insulation, some windows can have a strip of condensation that forms all the way around the roomside of the window. Usually, this occurs 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 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 instance, condensation is a mark of seal failure and the insulating glass should be replaced.

More likely 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 room.

igh indoor humidity can result in structural damage and even upset your health. Because these effects frequently go unnoticed 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 unresolved.

In the same way, left unaddressed, condensation issues can lead to window problems over time. Make sure to take chronic 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 working as they should, give Pella Windows and Doors in Overland Park a call or come into the showroom.

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