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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 impact your heating costs by retaining more temperate air in your room while defending against 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 stress! It isn’t time to start investigating 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 working well.

So, what is causing 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 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 created by the window or door product. Instead, it comes as a result of high humidity levels in your home.

As a matter of fact, 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 comes into contact with 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 room, condensation can be seen on windows initially, in the indication 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 dissipate.

Many 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 one on the other side doesn’t. Air circulation, varying room temperatures, air register location, and the type and size of the window can all increase the likelihood 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 are around a window.

Why do I occasionally see condensation on opposite sides of the window?
Your previous windows could have been drafty or didn’t feature the advanced, energy efficient components of modern windows. However, other home repairs, such as installing a new roof or siding, might also establish a tighter seal against air infiltration in your house. Due to that, your home may keep more humidity making condensation more likely to happen than before.

In the summer months, 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 grows 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 home isn’t leaving due to increased energy efficiency, there’s a greater chance to see external condensation in these situations.

You can manage exterior condensation by opening window coverings at night to warm up exterior glass and promote air circulation by removing any bushes that might be blocking windows. Adjusting the air conditioner a few degrees warmer can also improve the situation.

For roomside condensation, there are a few factors that can determine the humidity in your room. Here are a couple of 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–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 see why that humidity can often find no means of escape.

Because 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 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 Ruin My Windows?
One place where condensation on windows should become an immediate issue, however, is if condensation is appearing 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.

More often than not 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 unseen, potentially expensive problems to be found in your room.

igh indoor humidity can eventually cause 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 signal that humidity levels are too high. And while window condensation and musty odors might be seen as nuisances, they can develop into more severe concerns such as water stains on walls and ceilings if left alone.

In the same way, left unaddressed, condensation issues can mean window problems over time. Make sure to take continual roomside condensation seriously. Think of it as an early alarm to high humidity in your room, one that can easily be dealt with before it gets more severe. 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 working properly, give Pella in North Carolina a call or stop by the showroom.

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