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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 affect your heating costs by holding more temperate air in your house while defending against the elements outside. However, you may start to see condensation settling on your windows and doors during colder months.

If you find condensation on your window, don’t stress! It isn’t time to start diagnosing 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 doing their job.

So, what is causing the condensation on your windows? And, more importantly, what types of condensation should make you concerned about your window’s health? 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 caused by the window or door product. Rather, it comes because of high humidity levels in your room.

As a matter of fact, the presence of condensation more often than not is an outcome of the increased energy efficiency of your new windows. Air with more humidity keeps 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 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 the house’s 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 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, 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 play a role in 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 might have been drafty or didn’t have the advanced, energy efficient technology of modern windows. Additionally, other home repairs, such as adding a new roof or siding, might also create a tighter seal against air infiltration in your home. Due to that, your home may retain more humidity making condensation more likely to be seen than before.

In the warmer seasons, this same phenomenon can be noticed 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 establishes itself 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 house isn’t leaking due to increased energy efficiency, there’s a higher possibility to see external condensation at these times.

You can manage exterior condensation by opening window coverings at night to warm up exterior glass and promote air circulation by cutting back any shrubbery that might be interfering with windows. Setting 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 home. Here are a few common culprits that can lead to roomside condensation:

Sources of humidity in your home 

The most frequent way roomside humidity increases is through everyday living. 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. Add today’s energy efficient, well-insulated homes and you can start to get an idea why that humidity can often find no path to escape.

As a result of this better insulation, some windows can build a strip of condensation that forms all the way around the roomside of the window. Usually, 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 Damage My Windows?
One instance where condensation on windows should become an immediate concern, however, is if condensation is noticed between the two sealed panes of insulating glass in multi-pane windows. In this situation, condensation is a sign of seal failure and the insulating glass should be replaced.

Most often though, condensation on your windows doesn’t mean there is a concern with your windows. It serves as an alert to the possibility of other unnoticed, potentially expensive problems to be found in your house.

igh indoor humidity can lead to structural damage and even impact your health. Because these effects frequently go without notice in the wall cavities, attics and crawl spaces, the visible sign 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 unchecked.

In the same way, left unaddressed, condensation issues can cause window problems over time. Make sure to take chronic roomside condensation seriously. Think of it as an early warning to high humidity in your home, one that can easily be solved before it gets worse. 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 resisting condensation effectively, give Pella Windows and Doors in Salt Lake City a call or visit the showroom.

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