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Window Condensation: Understanding What It Means

Window Condensation: Understanding What It Means

It’s almost that weather where energy efficient windows can affect your heating costs by holding more temperate air in your house while resisting the elements outside. However, you may start to find condensation gathering on your windows and doors during colder months.

If you find condensation on your window, don’t panic! It isn’t time to start looking for something wrong with 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. Instead, it means your windows are being efficient.

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

Do my new windows or doors lead to condensation?
Some homeowners associate the sight of condensation in the months after installing new windows with possible problems during the installation process. Condensation on windows and doors is not produced by the window or door product. Rather, it comes due to high humidity levels in your home.

In reality, the signs of condensation more often than not is a result of the improved 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. Since glass surfaces are most likely the coldest part of the house, condensation shows up on windows first, in the indication of water droplets or frost on the roomside of the house’s window. As the air inside becomes drier, or as the glass surface becomes warmer, condensation begins to dissipate.

Numerous factors go into whether you might see condensation on your windows. You might even notice that a window in one part of your room has roomside condensation while another in the same room 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. Other factors like glass type, window coverings and screens and proximity to a water source can all have an impact on what levels of humidity can be noticed around a window.

Why do I occasionally see condensation on opposite sides of the window?
Your previous windows might have been drafty or didn’t have the advanced, energy efficient components 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 room. As a result, your home may retain 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 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 drops below the dew point of the outside air. Since the cooler air inside your room isn’t leaving 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 improve air circulation by cutting back any bushes that might be blocking windows. Adjusting the air conditioner a few degrees warmer can also help.

For roomside condensation, there are a few factors that can influence the humidity in your room. Here are some 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. 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–topping out at 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 path to escape.

Due to this better insulation, some windows can develop a strip of condensation that shows up all the way around the roomside of the window. Most often, this is created when the center of the glass stays warmer than the glass closest to the edge. It isn’t a sign that the window is leaking air or not functioning correctly.

Can Roomside Condensation Damage My Windows?
One place where condensation on windows should become an immediate warning, however, is if condensation is noticed 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 must be replaced.

More likely though, condensation on your windows doesn’t mean there is a defect with your windows. It serves as a sign to the possibility of other hidden, potentially pricey problems to be found in your room.

igh indoor humidity can result in structural damage and even upset your health. Because these effects frequently go unseen in the wall cavities, attics and crawl spaces, the visible sign 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 unresolved.

In the same way, left unaddressed, condensation issues can cause window problems over time. Make sure to take reoccurring roomside condensation seriously. Think of it as an early alert to high humidity in your home, one that can easily be resolved before it gets worse. Understanding condensation is just the beginning to keeping your home cozy and maintaining your windows. If you have any questions about condensation and whether your windows and doors are working properly, give Pella Windows and Doors in Charlotte a call or come into the showroom.

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