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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 affect your heating costs by holding more temperate air in your house while defending against the elements outside. However, you may start to find condensation appearing 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. 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 working well.

So, what is creating the condensation on your windows? And, more importantly, what types of condensation should make you concerned about your window’s stability? Here are the facts about window condensation:

Do my new windows or doors lead to condensation?
Some homeowners connect the signs 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. Rather, it comes as a result of high humidity levels in your house.

As it turns out, the presence of condensation more often than not is an indication 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. Due to the fact that glass surfaces are often the coldest part of the house, condensation appears on windows initially, in the presence 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 disappear.

Numerous 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, varying room temperatures, air register location, and the type and size of the window can all increase 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 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 have the advanced, energy efficient elements of modern windows. But, other home repairs, such as building a new roof or siding, might also build 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 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 room isn’t leaking due to increased energy efficiency, there’s a higher possibility to see external condensation at these times.

You can address exterior condensation by opening curtains at night to warm up exterior glass and improve air circulation by removing any bushes that might be obstructing 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 determine the humidity in your room. Here are a few common culprits that can cause roomside condensation:

Sources of humidity in your home 

The most commonly seen 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 increase moisture to the air in your home–up to four gallons or more per day in some homes. Include 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 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 a warning that the window is leaking air or not functioning correctly.

Can Roomside Condensation Hurt My Windows?
One instance 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 situation, condensation is a sign of seal failure and the insulating glass will need to 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 costly problems elsewhere in your home.

igh indoor humidity can lead to structural damage and even upset your health. Because these effects frequently go unseen 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 nuisances, they can evolve 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 continual roomside condensation seriously. Think of it as an early alarm to high humidity in your room, 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 properly, give Pella Windows and Doors in Decatur a call or visit the showroom.

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