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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 improve your heating bill by retaining more temperate air in your house while keeping the elements outside. However, you may start to find 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. As a matter of 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 leading to the condensation on your windows? And, more importantly, what kind 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 pair 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 produced by the window or door product. Instead, it comes because of high humidity levels in your house.

In reality, the signs of condensation more often than not is a result of the increased 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. Due to the fact that glass surfaces are usually the coldest part of the house, condensation can be seen on windows first, in the presence of water droplets or frost on the roomside of the window. As the air inside gets drier, or as the glass surface becomes warmer, condensation begins to lessen.

Many factors go into whether you might find condensation on your windows. You might even notice that a window in one part of your room has roomside condensation while another in the same room doesn’t. Air circulation, varying room temperatures, air register location, and the type and size of the window can all influence the chances 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 can be noticed 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 feature the advanced, energy efficient elements 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. Due to that, your home may hold more humidity making condensation more frequentl than before.

In the warmer seasons, this same phenomenon can be observed on the outside of your windows. Exterior condensation can gather as a result of high outdoor humidity, little or no wind, and a clear night sky. It establishes itself 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, it’s more likely to see external condensation at these times.

You can address exterior condensation by opening window coverings at night to warm up exterior glass and improve air circulation by cutting back any bushes 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 number of factors that can impact the humidity in your room. Here are some common culprits that can create roomside condensation:

Sources of humidity in your home 

The most common way roomside humidity increases is through everyday activity. Heat and moisture from 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–as much as 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 means of escape.

Due to this better insulation, some windows can build a strip of condensation that forms all the way around the roomside of the window. Usually, this happens 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 Damage My Windows?
One area where condensation on windows should become an immediate issue, however, is if condensation is seen 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 will need to be replaced.

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

igh 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 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 annoyances, they can evolve into more severe 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 reoccurring roomside condensation seriously. Think of it as an early warning to high humidity in your room, one that can easily be resolved before it gets more severe. Understanding condensation is just the beginning to keeping your home cozy and maintaining your windows. If you have any questions about condensation and whether your windows and doors are resisting condensation as they should, give Pella Windows and Doors in Birmingham a call or stop by the showroom.

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