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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 retaining more temperate air in your house while keeping the elements outside. However, you may start to see condensation appearing 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. 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 being efficient.

So, what is leading to the condensation on your windows? And, more importantly, what signs of condensation should cause concern about your window’s health? 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 potential problems during the installation process. Condensation on windows and doors is not created by the window or door product. Actually, it comes as a result of high humidity levels in your room.

As a matter of fact, the sight of condensation more often than not is a result of the improved energy efficiency of your new windows. Air with increased humidity retains 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 can be seen on windows first, in the indication of water droplets or frost on the roomside of the window. As the air inside becomes 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 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 influence the chances of roomside condensation. Other influnences such as 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 feature the advanced, energy efficient elements 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 house. Due to that, your home may hold more humidity making condensation more frequentl than before.

In the heat, this same phenomenon can be seen on the outside of your windows. Exterior condensation can gather because 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 home isn’t escaping due to increased energy efficiency, there’s a greater chance to see external condensation at these times.

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

For roomside condensation, there are a number of factors that can determine the humidity in your room. Here are some common culprits that can create roomside condensation:

Sources of humidity in your home 

The most common way roomside humidity increases is through everyday home activities. Heat and moisture from 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. Factor in 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 build 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 Hurt My Windows?
One area where condensation on windows should become an immediate warning, however, is if condensation is seen between the two sealed panes of insulating glass in multi-pane windows. In this situation, 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 defect with your windows. It serves as an indicator to the possibility of other unnoticed, potentially expensive problems elsewhere in your home.

igh indoor humidity can result in structural damage and even affect your health. Because these effects frequently go without notice 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 nuisances, they can evolve into more serious concerns such as water stains on walls and ceilings if left unchecked.

In the same way, left unaddressed, condensation issues can lead to window problems over time. Make sure to take continual 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 doing their jobs properly, give Pella Windows and Doors in San Antonio a call or stop by the showroom.

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