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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 improve your heating expenses by retaining more temperate air in your room while defending against 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 stress! It isn’t time to start investigating your window. As a matter of 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 signs of condensation should cause concern about your window’s stability? Here are the facts about window condensation:

Do my new windows or doors create condensation?
Some homeowners associate the presence 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 as a result of high humidity levels in your home.

As a matter of fact, the sight 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. Due to the fact that glass surfaces are most likely the coldest part of the room, condensation appears on windows initially, in the presence of water droplets or frost on the roomside of your window. As the air inside grows drier, or as the glass surface warms, condensation begins to lessen.

More than a few factors go into whether you might notice condensation on your windows. You might even find that a window in one part of your room has roomside condensation while one on the other side doesn’t. Air circulation, changes in room temperatures, air register location, and the type and size of the window can all impact the chances of roomside condensation. Other factors like glass type, window coverings and screens and proximity to a water source can all determine what levels of humidity appear around a window.

Why do I occasionally see condensation on opposite sides of the window?
Your previous windows may have been drafty or didn’t include the advanced, energy efficient technology of present-day windows. However, other home repairs, such as adding a new roof or siding, might also build a tighter seal against air infiltration in your room. 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 because of 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 cools below the dew point of the outside air. Since the cooler air inside your home isn’t leaking due to increased energy efficiency, it’s more likely to see external condensation at times like these.

You can manage exterior condensation by opening curtains at night to warm up exterior glass and increase air circulation by trimming any bushes that might be interfering with windows. Programming the air conditioner a few degrees warmer can also help.

For roomside condensation, there are a few factors that can impact the humidity in your room. Here are a couple of common culprits that can lead to roomside condensation:

Sources of humidity in your home 

The most common way roomside humidity increases is through everyday activity. Running 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–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 path to escape.

Due to this better insulation, some windows can have a strip of condensation that shows up all the way around the roomside of the window. Normally, this is created 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 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 situation, condensation is a result 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 an indicator to the possibility of other unnoticed, potentially expensive problems in other areas in your house.

igh indoor humidity can lead to structural damage and even impact 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 signal that humidity levels are too high. And while window condensation and musty odors might be seen as annoyances, 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 cause window problems over time. Make sure to take chronic roomside condensation seriously. Think of it as an early alert to high humidity in your house, one that can easily be dealt with before it gets more severe. Understanding condensation is just the beginning to keeping your home comfortable and maintaining your windows. If you have any questions about condensation and whether your windows and doors are working effectively, give Pella Windows and Doors in Memphis a call or come into the showroom.

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