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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 expenses by keeping 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 notice condensation on your window, don’t panic! It isn’t time to start diagnosing 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 causing the condensation on your windows? And, more importantly, what kind of condensation should cause concern about your window’s health? Here are the facts about window condensation:

Do my new windows or doors lead to condensation?
Some homeowners associate the sight of condensation in the months after installing new windows with potential problems during the installation process. Condensation on windows and doors is not produced 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 indication of the improved energy efficiency of your new windows. Air with high humidity holds 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. Since glass surfaces are most likely the coldest part of the room, condensation appears on windows more frequently, in the indication of water droplets or frost on the roomside of the window. As the air inside grows 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 another in the same room doesn’t. Air circulation, changing room temperatures, air register location, and the type and size of the window can all impact the likelihood of roomside condensation. Even the 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 might have been drafty or didn’t feature the advanced, energy efficient components of modern windows. Additionally, other home repairs, such as installing a new roof or siding, might also build a tighter seal against air infiltration in your home. Due to that, your home may keep more humidity making condensation more likely to happen than before.

In the summer months, this same phenomenon can be seen 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 establishes itself 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 room isn’t leaving due to increased energy efficiency, it’s more likely to see external condensation at times like these.

You can deal with exterior condensation by opening curtains at night to warm up exterior glass and improve air circulation by removing any bushes that might be obstructing windows. Programming 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 house. Here are some 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–as much as 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 path to escape.

Due to this better insulation, some windows can have a strip of condensation that shows up all the way around the roomside of the window. Normally, this is created 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 place where condensation on windows should become an immediate concern, however, is if condensation is appearing between the two sealed panes of insulating glass in multi-pane windows. In this situation, 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 problem with your windows. It serves as an indicator to the possibility of other hidden, potentially costly problems in other areas in your room.

High indoor humidity can lead to structural damage and even impact 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 clue that humidity levels are too high. And while window condensation and musty odors might be seen as annoyances, they can evolve into more serious 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 reoccurring roomside condensation seriously. Think of it as an early warning to high humidity in your home, one that can easily be resolved 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 working properly, give Pella Windows and Doors in Fargo a call or visit the showroom.

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