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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 retaining more temperate air in your room while resisting the elements outside. However, you may start to see condensation settling on your windows and doors during colder months.

If you see condensation on your window, don’t panic! It isn’t time to start diagnosing 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. Just the opposite, it means your windows are working well.

So, what is causing the condensation on your windows? And, more importantly, what kind of condensation should cause concern about your window’s strength? Here are the facts about window condensation:

Do my new windows or doors create condensation?
Some homeowners pair 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 due to high humidity levels in your house.

As it turns out, the sight of condensation more often than not is an indication of the increased energy efficiency of your new windows. Air with high 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 most likely the coldest part of the home, condensation appears on windows initially, in the presence of water droplets or frost on the roomside of the house’s window. As the air inside grows drier, or as the glass surface becomes warmer, condensation begins to dissipate.

More than a few 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 a different one doesn’t. Air circulation, changing room temperatures, air register location, and the type and size of the window can all impact the likelihood of roomside condensation. Other factors like glass type, window coverings and screens and proximity to a water source can all determine what levels of humidity can be noticed 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 technology of modern windows. But, other home repairs, such as building a new roof or siding, might also establish a tighter seal against air infiltration in your house. Because of that, your home may keep more humidity making condensation more likely to be seen than before.

In the heat, this same phenomenon can be observed on the outside of your windows. Exterior condensation can appear 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 is cooled below the dew point of the outside air. Since the cooler air inside your home isn’t leaving due to increased energy efficiency, it’s more likely to see external condensation at times like these.

You can deal with exterior condensation by opening curtains at night to warm up exterior glass and promote air circulation by cutting back any shrubbery that might be interfering with windows. Setting the air conditioner a few degrees warmer can also help.

For roomside condensation, there are a group of factors that can impact the humidity in your room. Here are some 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–as much as four gallons or more per day in some homes. Add 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 shows up all the way around the roomside of the window. Normally, this occurs 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 area 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 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 hidden, potentially pricey problems elsewhere 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 clue that humidity levels are too high. And while window condensation and musty odors might be seen as bothersome, they can grow into more serious 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 chronic roomside condensation seriously. Think of it as an early warning to high humidity in your home, one that can easily be solved 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 doing their jobs as they should, give Pella Windows and Doors in Evansville a call or visit the showroom.

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