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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 impact your heating expenses by retaining more temperate air in your home while resisting the elements outside. However, you may start to notice condensation gathering 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. The fact is, 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 working well.

So, what is leading to the condensation on your windows? And, more importantly, what signs of condensation should make you concerned about your window’s health? Here are the facts about window condensation:

Do my new windows or doors cause condensation?
Some homeowners pair the signs of condensation in the months after installing new windows with unnoticed problems during the installation process. Condensation on windows and doors is not produced by the window or door product. Instead, it comes as a result of high humidity levels in your room.

As a matter of fact, the presence of condensation more often than not is an indication of the better 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. Because glass surfaces are most likely the coldest part of the house, condensation shows up on windows more frequently, in the form of water droplets or frost on the roomside of the window. As the air inside becomes 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 notice 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 influence the presence of roomside condensation. Other factors like glass type, window coverings and screens and proximity to a water source can all have an impact on what levels of humidity are 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 include the advanced, energy efficient technology of present-day windows. However, other home repairs, such as adding a new roof or siding, might also establish a tighter seal against air infiltration in your home. As a result, your home may retain more humidity making condensation more likely to be seen than before.

In the summer months, this same phenomenon can be noticed 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 establishes itself in the same way as roomside condensation, when the temperature of the glass drops 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 greater chance to see external condensation at times like these.

You can address exterior condensation by opening window coverings at night to warm up exterior glass and promote air circulation by trimming any shrubbery 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 influence the humidity in your room. Here are a couple of common culprits that can lead to roomside condensation:

Sources of humidity in your home 

The most commonly seen way roomside humidity increases is through everyday living. 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–as much as four gallons or more per day in some homes. Include today’s energy efficient, well-insulated homes and you can start to get an idea why that humidity can often find no path to escape.

Because of this better insulation, some windows can have a strip of condensation that appears all the way around the roomside of the window. Most often, 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 Hurt My Windows?
One instance where condensation on windows should become an immediate warning, however, is if condensation is seen 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 likely though, condensation on your windows doesn’t mean there is a defect with your windows. It serves as a sign to the possibility of other unseen, potentially costly problems in other areas in your house.

High indoor humidity can lead to structural damage and even impact your health. Because these effects frequently go unseen 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 develop into more severe concerns such as water stains on walls and ceilings if left unresolved.

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 alarm to high humidity in your room, one that can easily be dealt with before it gets worse. 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 working as they should, give Pella Windows and Doors Southwest in Albuquerque a call or come into the showroom.

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