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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 holding more temperate air in your room 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 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. Just the opposite, it means your windows are working well.

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

Do my new windows or doors cause condensation?
Some homeowners connect 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. Instead, it comes due to high humidity levels in your home.

As it turns out, the presence of condensation more often than not is an indication of the increased energy efficiency of your new windows. Air with increased 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 usually the coldest part of the room, condensation shows up on windows more frequently, in the form of water droplets or frost on the roomside of the window. As the air inside becomes drier, or as the glass surface becomes warmer, condensation begins to lessen.

Numerous 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 influence the chances of roomside condensation. Other influnences such as 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 at times 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. Additionally, other home repairs, such as building a new roof or siding, might also establish a tighter seal against air infiltration in your house. As a result, your home may retain more humidity making condensation more frequentl than before.

In the heat, this same phenomenon can be noticed 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 establishes itself 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 higher possibility to see external condensation in these situations.

You can deal with exterior condensation by opening shades at night to warm up exterior glass and improve air circulation by trimming any bushes that might be interfering with windows. Adjusting the air conditioner a few degrees warmer can also improve the situation.

For roomside condensation, there are a group of factors that can impact the humidity in your home. Here are a few common culprits that can cause roomside condensation:

Sources of humidity in your home 

The most common way roomside humidity increases is through everyday living. 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–up to four gallons or more per day in some homes. Add today’s energy efficient, well-insulated homes and you can start to understand why that humidity can often find no way to escape.

Due to this better insulation, some windows can have a strip of condensation that appears 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 an indication 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 issue, however, is if condensation is seen between the two sealed panes of insulating glass in multi-pane windows. In this instance, condensation is a result of seal failure and the insulating glass must be replaced.

Most often 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 in other areas in your home.

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 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 annoyances, 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 chronic roomside condensation seriously. Think of it as an early warning 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 comfy and maintaining your windows. If you have any questions about condensation and whether your windows and doors are resisting condensation as they should, give Pella Windows and Doors in Baltimore a call or come into the showroom.

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