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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 improve your heating costs by holding more temperate air in your room while keeping 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 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. Rather, it means your windows are doing their job.

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

Do my new windows or doors lead to condensation?
Some homeowners connect the presence 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 due to high humidity levels in your room.

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 holds 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 house, condensation can be seen on windows more frequently, in the indication 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 dissipate.

Many factors go into whether you might find condensation on your windows. You might even find that a window in one part of your room has roomside condensation while one on the other side doesn’t. Air circulation, changing room temperatures, air register location, and the type and size of the window can all impact the presence 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 might have been drafty or didn’t include the advanced, energy efficient components of today’s windows. But, other home repairs, such as installing a new roof or siding, might also establish a tighter seal against air infiltration in your house. As a result, your home may hold more humidity making condensation more frequentl than before.

In the summer months, this same phenomenon can be noticed 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 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 leaving due to increased energy efficiency, it’s more likely to see external condensation at these times.

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

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

Sources of humidity in your home 

The most common 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 bring moisture to the air in your home–up to 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.

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. Most often, 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 Ruin My Windows?
One place where condensation on windows should become an immediate issue, however, is if condensation is appearing between the two sealed panes of insulating glass in multi-pane windows. In this situation, condensation is a sign 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 alert to the possibility of other hidden, potentially expensive problems elsewhere in your room.

igh indoor humidity can result in structural damage and even upset your health. Because these effects frequently go without notice in the wall cavities, attics and crawl spaces, the visible sign 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 nuisances, they can grow into more immediate 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 room, one that can easily be dealt with before it gets more severe. 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 Monroe a call or visit the showroom.

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