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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 impact your heating expenses by holding more temperate air in your home while defending against the elements outside. However, you may start to see condensation gathering on your windows and doors during colder months.

If you find condensation on your window, don’t worry! It isn’t time to start looking for something wrong with 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. Instead, it means your windows are being efficient.

So, what is creating 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 potential problems during the installation process. Condensation on windows and doors is not produced by the window or door product. Actually, it comes as a result of high humidity levels in your room.

As it turns out, the presence of condensation more often than not is an indication of the improved energy efficiency of your new windows. Air with high 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 usually the coldest part of the house, condensation shows up on windows initially, in the indication of water droplets or frost on the roomside of the house’s window. As the air inside gets drier, or as the glass surface warms, condensation begins to disappear.

Many factors go into whether you might see condensation on your windows. You might even discover that a window in one part of your room has roomside condensation while a different one doesn’t. Air circulation, changing 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 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 could have been drafty or didn’t have the advanced, energy efficient components of modern windows. However, other home repairs, such as installing a new roof or siding, might also establish a tighter seal against air infiltration in your room. As a result, your home may keep more humidity making condensation more likely to happen than before.

In the warmer seasons, this same phenomenon can be noticed on the outside of your windows. Exterior condensation can appear 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 room isn’t escaping due to increased energy efficiency, there’s a higher possibility to see external condensation at these times.

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 help.

For roomside condensation, there are a group of factors that can determine the humidity in your house. Here are a few 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. Factor in today’s energy efficient, well-insulated homes and you can start to understand why that humidity can often find no way to escape.

Due to this better insulation, some windows can develop a strip of condensation that appears all the way around the roomside of the window. Usually, this occurs when the center of the glass stays warmer than the glass closest to the edge. It isn’t a warning 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 warning, however, is if condensation is appearing between the two sealed panes of insulating glass in multi-pane windows. In this situation, condensation is a mark of seal failure and the insulating glass will need to be replaced.

Most often though, condensation on your windows doesn’t mean there is a problem with your windows. It serves as a sign to the possibility of other unseen, potentially costly problems to be found in your home.

High indoor humidity can eventually cause structural damage and even affect your health. Because these effects frequently go unseen in the wall cavities, attics and crawl spaces, the visible sign 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 annoyances, they can grow into more serious concerns such as water stains on walls and ceilings if left alone.

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 alarm to high humidity in your house, one that can easily be solved 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 doing their jobs effectively, give Pella Windows & Doors - Kelowna in Kelowna a call or come into the showroom.

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