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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 affect your heating costs by holding more temperate air in your home while resisting the elements outside. However, you may start to find condensation settling on your windows and doors during colder months.

If you notice condensation on your window, don’t panic! It isn’t time to start looking for something wrong with 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. Instead, it means your windows are working well.

So, what is causing the condensation on your windows? And, more importantly, what kind 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 pair the sight of condensation in the months after installing new windows with unnoticed 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 home.

In reality, the signs of condensation more often than not is an outcome of the increased energy efficiency of your new windows. Air with increased 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 often the coldest part of the room, condensation can be seen on windows first, in the presence of water droplets or frost on the roomside of the house’s window. As the air inside becomes drier, or as the glass surface warms, condensation begins to disappear.

More than a few factors go into whether you might see condensation on your windows. You might even find that a window in one part of your room has roomside condensation while a different one doesn’t. Air circulation, varying room temperatures, air register location, and the type and size of the window can all increase the chances of roomside condensation. Other influnences such as 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 occasionally see condensation on opposite sides of the window?
Your previous windows might have been drafty or didn’t feature the advanced, energy efficient components of today’s windows. However, other home repairs, such as installing a new roof or siding, might also create a tighter seal against air infiltration in your house. As a result, your home may hold more humidity making condensation more likely to be seen than before.

In the warmer seasons, this same phenomenon can be seen 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 cools below the dew point of the outside air. Since the cooler air inside your house isn’t leaving due to increased energy efficiency, there’s a greater chance to see external condensation at these times.

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

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 living. Running 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. Include today’s energy efficient, well-insulated homes and you can start to understand why that humidity can often find no means of 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. Normally, 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 place where condensation on windows should become an immediate concern, 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.

More often than not 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 unseen, potentially costly problems to be found in your home.

High 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 sign that humidity levels are too high. And while window condensation and musty odors might be seen as bothersome, they can evolve into more serious concerns such as water stains on walls and ceilings if left alone.

In the same way, left unaddressed, condensation issues can lead to window problems over time. Make sure to take reoccurring roomside condensation seriously. Think of it as an early alert to high humidity in your house, one that can easily be dealt with before it gets serious. 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 working effectively, give McComb Window & Door in Lafayette a call or stop by the showroom.

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