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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 impact your heating expenses by holding more temperate air in your home while defending against the elements outside. However, you may start to notice condensation settling on your windows and doors during colder months.

If you notice condensation on your window, don’t worry! It isn’t time to start investigating 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 doing their job.

So, what is creating 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 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 created by the window or door product. Actually, it comes due to high humidity levels in your house.

As it turns out, the presence of condensation more often than not is an indication of the improved 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 usually the coldest part of the room, condensation can be seen on windows initially, in the presence of water droplets or frost on the roomside of your window. As the air inside grows drier, or as the glass surface heats up, condensation begins to lessen.

More than a few 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, changes in room temperatures, air register location, and the type and size of the window can all influence the likelihood 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 are 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. However, other home repairs, such as adding a new roof or siding, might also establish a tighter seal against air infiltration in your room. As a result, your home may hold 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 gather because of 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, there’s a higher possibility to see external condensation at these times.

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

For roomside condensation, there are a number of factors that can influence the humidity in your home. 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. 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 way to escape.

As a result of this better insulation, some windows can develop a strip of condensation that shows up all the way around the roomside of the window. Most often, this happens 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 Hurt My Windows?
One area where condensation on windows should become an immediate concern, however, is if condensation is noticed 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 should be replaced.

More often than not though, condensation on your windows doesn’t mean there is a concern with your windows. It serves as an indicator to the possibility of other hidden, potentially pricey problems in other areas in your home.

High indoor humidity can result in structural damage and even upset your health. Because these effects frequently go unnoticed in the wall cavities, attics and crawl spaces, the visible indication 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 annoyances, 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 mean window problems over time. Make sure to take chronic 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 doing their jobs properly, give Pella Windows and Doors in Raleigh a call or visit the showroom.

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