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Window Condensation: Understanding What It Means

Window Condensation: Understanding What It Means

It’s almost that time of year where energy efficient windows can affect your heating costs by holding more temperate air in your room while defending against 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 worry! It isn’t time to start diagnosing your window. The fact is, 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 being efficient.

So, what is causing the condensation on your windows? And, more importantly, what signs of condensation should cause concern about your window’s health? 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 possible problems during the installation process. Condensation on windows and doors is not caused by the window or door product. Instead, it comes as a result of high humidity levels in your home.

In reality, the sight of condensation more often than not is an indication of the improved energy efficiency of your new windows. Air with more 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. Because glass surfaces are most likely the coldest part of the house, condensation shows up on windows more frequently, in the form of water droplets or frost on the roomside of your window. As the air inside grows drier, or as the glass surface becomes warmer, condensation begins to lessen.

Numerous factors go into whether you might find condensation on your windows. You might even discover 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 influence the presence of roomside condensation. Even the glass type, window coverings and screens and proximity to a water source can all have an impact on what levels of humidity are 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 have the advanced, energy efficient elements of modern windows. However, 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 hold 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 due to 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 house isn’t escaping due to increased energy efficiency, it’s more likely to see external condensation in these situations.

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

For roomside condensation, there are a group of factors that can determine the humidity in your home. Here are some common culprits that can create roomside condensation:

Sources of humidity in your home 

The most frequent way roomside humidity increases is through everyday home activities. Taking showers and baths, cooking and washing dishes, doing laundry, even the dog’s water bowl can all add moisture to the air in your home–topping out at 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 develop a strip of condensation that shows up 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 sign that the window is leaking air or not functioning correctly.

Can Roomside Condensation Ruin 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 should be replaced.

Most often though, condensation on your windows doesn’t mean there is a problem with your windows. It serves as an alert to the possibility of other unnoticed, potentially pricey problems to be found in your house.

igh indoor humidity can lead to structural damage and even upset 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 sign that humidity levels are too high. And while window condensation and musty odors might be seen as nuisances, they can grow into more serious concerns such as water stains on walls and ceilings if left unresolved.

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 house, one that can easily be resolved before it gets worse. 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 properly, give Pella Windows and Doors in Fall River a call or come into the showroom.

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