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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 home while keeping the elements outside. However, you may start to notice condensation appearing on your windows and doors during colder months.

If you find 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 doing their job.

So, what is creating the condensation on your windows? And, more importantly, what types of condensation should raise alarms about your window’s strength? 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 caused by the window or door product. Actually, it comes due to high humidity levels in your house.

As it turns out, the signs of condensation more often than not is a result of the better energy efficiency of your new windows. Air with high humidity keeps 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 appears on windows first, in the indication of water droplets or frost on the roomside of the window. As the air inside grows drier, or as the glass surface becomes warmer, condensation begins to disappear.

Many factors go into whether you might find condensation on your windows. You might even notice that a window in one part of your room has roomside condensation while one on the other side doesn’t. Air circulation, changing room temperatures, air register location, and the type and size of the window can all influence the presence of roomside condensation. Other factors like glass type, window coverings and screens and proximity to a water source can all play a role in what levels of humidity can be noticed around a window.

Why do I sometimes see condensation on opposite sides of the window?
Your previous windows may have been drafty or didn’t feature the advanced, energy efficient technology of present-day windows. Additionally, other home repairs, such as installing a new roof or siding, might also create a tighter seal against air infiltration in your room. Because of that, your home may keep more humidity making condensation more likely to happen than before.

In the warmer seasons, 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 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 shades at night to warm up exterior glass and improve air circulation by cutting back any plants that might be obstructing windows. Setting the air conditioner a few degrees warmer can also make a difference.

For roomside condensation, there are a number of factors that can determine the humidity in your house. Here are a couple of common culprits that can cause roomside condensation:

Sources of humidity in your home 

The most common 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 increase moisture to the air in your home–up to four gallons or more per day in some homes. Factor in today’s energy efficient, well-insulated homes and you can start to understand 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 shows up all the way around the roomside of the window. Normally, 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 Damage My Windows?
One area 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 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 unseen, potentially pricey problems to be found in your house.

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 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 annoyances, they can develop into more severe concerns such as water stains on walls and ceilings if left unchecked.

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 alert to high humidity in your home, one that can easily be resolved before it gets serious. Understanding condensation is just the beginning to keeping your home comfortable and maintaining your windows. If you have any questions about condensation and whether your windows and doors are working effectively, give Pella Windows and Doors in Shrewsbury a call or visit the showroom.

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