If you’re noticing condensation on your windows, you might be wondering whether or not you should be concerned. The short answer is: It depends. It depends on where the condensation is forming, i.e., inside, outside, or in between the glass. It also depends on the time of year and even the age of your home — condensation on windows in a newly built home is a common temporary occurrence.
Let’s explore what you need to know about condensation on your windows.
When warm air comes in contact with a cooler surface, condensation forms. The same way your glass of ice water “sweats” on a hot summer’s day, your window might fog up on a cold winter’s day.
Condensation happens because the air can only hold so much water vapor (moisture) before it changes into liquid water droplets. The amount of moisture the air can hold varies by temperature. Because cold air can hold less moisture than warm air, window condensation happens most often in the wintertime when your windows, warmed from the heat inside your house, meet the cold air outside.
Where the condensation forms is the key to understanding if it is a problem.
When condensation forms on the inside of your windows, it can block your view, drip on the floor, or freeze on the glass. It can be annoying, and it can cause problems if left unchecked. The reason condensation forms inside the window is because the humidity level is too high indoors, not because there is something wrong with the window.
Humidity is the moisture in the air. It forms when we breathe, when we cook, when we shower, when we do laundry, and other everyday activities. It’s always present in air, and it’s not an inherently bad thing — as you’re probably aware if you’ve ever bought a humidifier. However, humidity can cause damage to your home if it’s too high for too long — for example: cracking, peeling or blistering paint; mildew and mold; and more.
If you’re noticing condensation on the inside of your windows in the winter, it’s a warning sign and you should take action.
To help prevent condensation inside your windows, reduce indoor humidity. Here are a few ways to do that:
Tip: In the winter months, you should aim for 30 to 35 percent humidity in your home. Some thermostats measure humidity. If yours doesn’t, you can buy an inexpensive tool called a hygrometer to measure humidity.
When condensation forms on the outside of your windows, it’s really just dew — just like wet grass on a summer morning. Dew forms on windows when the glass is cooler than the dew point (the point when water vapor turns into liquid water droplets.)
It’s most common to see condensation outside your windows on spring and fall mornings when humidity levels are higher and cool nights are followed by warm days. You may only notice this a few times a year. When you do, rest assured, it’s the result of conditions outside — not a sign your windows are failing.
In fact, condensation on the outside of the window is a sign of energy efficiency. It means the outside pane of glass is thoroughly insulated from the heat indoors.
When the seal on your window breaks and condensation starts to form in between the panes of glass, you won’t be able to prevent it from forming. This condensation is an indication that your window is no longer performing well, which means the ideal solution is to replace your windows. Here are a few things to keep in mind when considering replacement:
Did you know? You can make selections that fool the eye. So let’s say you live in a traditional home full of double-hung windows, but you’d like to replace a few of those windows with casements because of their superior energy efficiency. You could order your casements with grilles applied in such a way that the new windows look like they are double hung.
