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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 keeping more temperate air in your room while keeping the elements outside. However, you may start to see condensation settling on your windows and doors during colder months.

If you notice condensation on your window, don’t worry! It isn’t time to start investigating 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 doing their job.

So, what is creating the condensation on your windows? And, more importantly, what types of condensation should cause concern about your window’s health? Here are the facts about window condensation:

Do my new windows or doors cause condensation?
Some homeowners pair the presence of condensation in the months after installing new windows with possible problems during the installation process. Condensation on windows and doors is not caused by the window or door product. Actually, it comes as a result of high humidity levels in your home.

In reality, the presence of condensation more often than not is a result of the better energy efficiency of your new windows. Air with more humidity holds water vapor until it connects with a surface temperature less than or equal to the dew point—the temperature at which air becomes saturated and produces dew. Since glass surfaces are often the coldest part of the house, condensation shows up on windows initially, in the presence of water droplets or frost on the roomside of your window. As the air inside becomes drier, or as the glass surface heats up, condensation begins to disappear.

More than a few 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 influence the presence of roomside condensation. Other factors like 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 might have been drafty or didn’t have the advanced, energy efficient technology of today’s windows. But, other home repairs, such as adding a new roof or siding, might also create a tighter seal against air infiltration in your house. Due to that, your home may retain more humidity making condensation more frequentl than before.

In the warmer seasons, this same phenomenon can be noticed 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 is cooled below the dew point of the outside air. Since the cooler air inside your room isn’t leaking due to increased energy efficiency, it’s more likely to see external condensation at times like these.

You can deal with exterior condensation by opening window coverings at night to warm up exterior glass and increase air circulation by trimming any shrubbery that might be blocking windows. Adjusting the air conditioner a few degrees warmer can also make a difference.

For roomside condensation, there are a group of factors that can influence the humidity in your home. Here are a couple of common culprits that can cause roomside condensation:

Sources of humidity in your home 

The most frequent 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 increase 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 understand why that humidity can often find no means of escape.

As a result of this better insulation, some windows can have a strip of condensation that appears 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 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 mark of seal failure and the insulating glass must be replaced.

More likely 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 expensive problems to be found in your house.

igh indoor humidity can lead to structural damage and even affect your health. Because these effects frequently go unseen in the wall cavities, attics and crawl spaces, the visible indication 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 bothersome, they can develop into more immediate concerns such as water stains on walls and ceilings if left alone.

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 house, one that can easily be solved before it gets serious. 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 as they should, give Pella Windows and Doors in Newport a call or come into the showroom.

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