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Condensation Around Your Windows?

Have you noticed the windows in your home are continually fogged up? Does it seem like they are collecting moisture? Fogged windows or windows that collect moisture is a frustrating problem. However, it is not an automatic indicator that you need to replace all the windows in your home. In fact, the windows may be an indication of an entirely different problem.

This post explains the relationship between windows and condensation, helps you identify the cause, and goes over a few options to cut down or eliminate the problem.

What Causes Condensation

It might surprise you to learn that windows do not cause condensation. Although, they are frequently the first place condensation can be seen. Warm air can hold more moisture than cold air. As air cools, it contracts and its moisture condenses. Therefore, when warm, humid air around the window is cooled by the surface of the window, condensation forms. If the air is very humid and the temperature difference between the surface of the window and the air is large, it is possible for the moisture to run down the surface of the glass and pool on the surfaces below the window. Materials used to manufacture window frames and the other factors related to manufacturing have an effect on the likelihood of the windows having a problem with condensation and the degree of the problem if it does occur. I will go into more later in this post.

When is Condensation Not Something to Worry About

Not all condensation on windows is a problem. The exterior of windows (the side exposed to the outside) are going to have moisture and/or condensation on them at some point. The window is specifically designed to deal with and appropriately shed moisture. Home owners in hotter, more humid climates (can I get a shout out from my Texas folks) are going to notice more condensation on the exterior of the windows than those in dryer, more temperate climates. While it may obstruct views and be annoying to homeowners, it is not something to worry about. Exterior condensation is not a sign of inefficient windows.

When to Worry About Window Condensation

There are two instances where condensation on and around your windows is something you need to address. The first is when there is condensation forming between the panes of double or triple pane windows. The second is when there is condensation on the interior of the windows.

To figure out what is the cause of your window condensation, try this easy test. Run your finger through the area where the condensation is formed. If your finger gets wet and leaves a trail through the condensation.

Seal Failure

If when you did the above test, your finger is dry and there is not a trail formed through the moisture on the glass, you likely have seal failure in your double pane or triple pane windows causing condensation to form between the panes of glass. (To learn more about the causes and solutions for seal failure, click here). If you have determined seal failure is the cause of your window condensation, it is time to start looking into window replacement options. To read about window replacement versus other option to fix seal failure, like glass replacement, click here.

Indoor Humidity

If when you did the above test your finger is wet and you left a trail through the condensation, it's on the room side of the glass. This tells you that the condensation is a result of excessive indoor humidity. Everyday living such as showers, cooking, doing laundry, washing dishes, and even breathing add moisture to the air in your home. Today's energy efficient, well insulated homes help keep heat and cold out and energy costs as low as possible. Those same things that keep the outside from getting in, keep moisture from venting to the outdoors. Under the right conditions, even newly installed, very efficient windows can have condensation on the room side of the glass.

While the material the window frame is manufactured from can have an effect on the degree of the the problem, aluminum frames will condensate the most and wood the least under the right conditions. The most effective way to control indoor humidity is a well functioning HVAC system. Even the best HVAC systems available can not effectively control the humidity in your home if you are not running it enough. So, the first step is to figure out if your HVAC system is functioning properly and, if it is, are you running it in such a way that does not allow for proper control of the humidity in your home.

A Further Note on Indoor Humidity

Many people raise and lower the thermostat, depending on the season, in order to save money on their electric bill. If this is not causing indoor humidity issues, that's great, keep it up and save those dollars where you can. However, if it is causing indoor humidity issues in your home, it may end up costing you more money in the long run than it saves. Mold and mildew thrive in moist areas with plenty of organic material, such as wood, plaster, and some types of insulation. Mold and mildew has the potential to cause health problems in certain individuals.

Other problems can occur with your home causing higher repair and upkeep costs. Because humid indoor air tends to be under higher pressure than outdoor air, indoor air constantly pushes its way outward to the area of lower pressure. This puts extra pressure on wood, plaster, insulation, and concrete. The process can cause insulation to deteriorate, paint to blister and peel, unsightly stains on walls and ceilings, rotting of floors, wall supports and other structural supports and foundation damage.

Regardless of the cause of fogged windows, it can be a very frustrating problem for homeowners.

By figuring out the cause of the problem, the solution is much easier to attain. Thank you for reading this post. Please leave questions in the comments.

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