Blog
Window Condensation: Understanding What It Means

Window Condensation: Understanding What It Means

It’s almost that weather where energy efficient windows can affect your heating bill by keeping more temperate air in your home while keeping the elements outside. However, you may start to see condensation appearing on your windows and doors during colder months.

If you see condensation on your window, don’t stress! 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. Rather, it means your windows are working well.

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

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

As it turns out, the signs of condensation more often than not is an indication of the better energy efficiency of your new windows. Air with more humidity keeps 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 often the coldest part of the home, condensation shows up on windows more frequently, in the form of water droplets or frost on the roomside of your window. As the air inside becomes drier, or as the glass surface heats up, condensation begins to disappear.

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, changes in room temperatures, air register location, and the type and size of the window can all influence the presence 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 appear 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 elements of today’s windows. Additionally, other home repairs, such as building a new roof or siding, might also build a tighter seal against air infiltration in your home. As a result, your home may keep more humidity making condensation more frequentl than before.

In the warmer seasons, this same phenomenon can be seen 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 forms 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 leaking due to increased energy efficiency, there’s a higher possibility 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 shrubbery that might be obstructing windows. Setting the air conditioner a few degrees warmer can also make a difference.

For roomside condensation, there are a group of factors that can determine the humidity in your house. Here are some common culprits that can lead to roomside condensation:

Sources of humidity in your home 

The most common way roomside humidity increases is through everyday activity. 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–up to 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.

Due to this better insulation, some windows can have a strip of condensation that appears 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 place 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 sign 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 concern with your windows. It serves as a sign to the possibility of other unseen, potentially pricey problems elsewhere in your home.

igh indoor humidity can eventually cause 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 nuisances, they can grow 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 continual roomside condensation seriously. Think of it as an early alarm to high humidity in your house, 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 working properly, give Pella Windows and Doors in Owensboro a call or visit the showroom.

Back to Blog