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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 bill by keeping more temperate air in your home while keeping the elements outside. However, you may start to see condensation settling on your windows and doors during colder months.

If you find condensation on your window, don’t panic! 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. Rather, it means your windows are working well.

So, what is leading to the condensation on your windows? And, more importantly, what types of condensation should cause concern about your window’s stability? Here are the facts about window condensation:

Do my new windows or doors create condensation?
Some homeowners pair the presence of condensation in the months after installing new windows with unnoticed problems during the installation process. Condensation on windows and doors is not produced by the window or door product. Instead, it comes as a result of high humidity levels in your home.

As a matter of fact, the presence of condensation more often than not is an indication of the improved energy efficiency of your new windows. Air with increased humidity retains 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. Due to the fact that glass surfaces are usually the coldest part of the house, condensation can be seen on windows more frequently, in the form of water droplets or frost on the roomside of the house’s window. As the air inside grows drier, or as the glass surface heats up, condensation begins to dissipate.

Many factors go into whether you might notice 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, varying room temperatures, air register location, and the type and size of the window can all impact the chances 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 appear 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 feature the advanced, energy efficient technology of modern windows. Additionally, other home repairs, such as adding a new roof or siding, might also build a tighter seal against air infiltration in your home. Because of that, your home may keep 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 form because of high outdoor humidity, little or no wind, and a clear night sky. It grows 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 leaking due to increased energy efficiency, there’s a greater chance to see external condensation in these situations.

You can deal with exterior condensation by opening curtains at night to warm up exterior glass and increase air circulation by removing any bushes that might be interfering with windows. Adjusting the air conditioner a few degrees warmer can also make a difference.

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

Sources of humidity in your home 

The most commonly seen way roomside humidity increases is through everyday activity. 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–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.

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. Usually, this occurs when the center of the glass stays warmer than the glass closest to the edge. It isn’t a warning that the window is leaking air or not functioning correctly.

Can Roomside Condensation Damage My Windows?
One instance 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 case, 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 indicator to the possibility of other unnoticed, potentially expensive problems elsewhere in your room.

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 indication 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 nuisances, they can evolve 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 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 working as they should, give Pella Windows and Doors in Westerly a call or come into the showroom.

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