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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 expenses by holding more temperate air in your home while keeping the elements outside. However, you may start to notice condensation gathering on your windows and doors during colder months.

If you find condensation on your window, don’t worry! It isn’t time to start looking for something wrong with your window. The fact is, 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 working well.

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

Do my new windows or doors lead to condensation?
Some homeowners pair 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. Rather, it comes due to high humidity levels in your house.

As it turns out, the signs of condensation more often than not is an outcome of the better energy efficiency of your new windows. Air with more 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. Due to the fact that glass surfaces are usually the coldest part of the house, condensation shows up on windows first, in the form of water droplets or frost on the roomside of the house’s window. As the air inside becomes drier, or as the glass surface heats up, condensation begins to lessen.

Many factors go into whether you might find condensation on your windows. You might even notice that a window in one part of your room has roomside condensation while another in the same room doesn’t. Air circulation, varying room temperatures, air register location, and the type and size of the window can all impact the likelihood 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 have the advanced, energy efficient technology of modern windows. But, other home repairs, such as building a new roof or siding, might also create a tighter seal against air infiltration in your home. Due to that, your home may hold more humidity making condensation more likely to happen than before.

In the heat, this same phenomenon can be seen on the outside of your windows. Exterior condensation can appear as a result of high outdoor humidity, little or no wind, and a clear night sky. It establishes itself 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 house isn’t leaking 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 improve air circulation by removing any plants that might be obstructing windows. Setting the air conditioner a few degrees warmer can also make a difference.

For roomside condensation, there are a number of factors that can influence the humidity in your house. Here are a few common culprits that can create roomside condensation:

Sources of humidity in your home 

The most commonly seen way roomside humidity increases is through everyday home activities. Taking showers and baths, cooking and washing dishes, doing laundry, even the dog’s water bowl can all bring moisture to the air in your home–up to four gallons or more per day in some homes. Include 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 develop 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 warning that the window is leaking air or not functioning correctly.

Can Roomside Condensation Ruin My Windows?
One instance where condensation on windows should become an immediate warning, however, is if condensation is noticed 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 will need to be replaced.

More often than not 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 unnoticed, potentially costly problems to be found in your house.

High indoor humidity can lead to structural damage and even upset your health. Because these effects frequently go without notice in the wall cavities, attics and crawl spaces, the visible presence of condensation on glass is a good clue that humidity levels are too high. And while window condensation and musty odors might be seen as annoyances, they can grow into more immediate 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 reoccurring roomside condensation seriously. Think of it as an early alarm to high humidity in your home, one that can easily be solved before it gets more severe. 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 properly, give McComb Window & Door in Bloomington, IN a call or come into the showroom.

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