Foggy Window FAQs

You might not know what causes it yet, or how to fix it, but most people have seen foggy windows. This is a common term to describe windows that have "misted up." You might have seen it in your home, someone else's, or even in a vehicle - particularly when the weather is cold.

So let's learn more about what causes foggy windows, whether it's something you need to worry about, and what you need to do if you want to prevent it.

Most Important Foggy Window FAQs

The good news is that there is not that much that you need to learn about foggy windows. It's a pretty simple problem, with some easy solutions.

What Causes Foggy Windows In a House?

There's a very simple reason why you get condensation on windows: the temperature and humidity on the two sides of the window are different. If one side of the window is cold and dry, and the other is warmer and more humid, you will get condensation. With modern HVAC systems, that happens very often in our homes.

Can Foggy Windows Be Repaired?

That depends on what is causing the foggy windows, and where it is occurring. Foggy windows also aren't necessarily a bad thing. This is usually a sign that your windows are doing their job, sealing the air inside the house in and the air outside out. So you first want to establish that this is causing a problem. If it's not, you probably don't need to do any repairs.

How Do You Prevent Foggy Windows?

Since foggy windows are usually caused by a difference in humidity, the first thing you need to establish is where your windows are fogging up. Is it inside, or outside, or between two window layers?

If the fog is inside your house, it's probably due to your use of the home. Anything that causes steam and humidity like a humidifier, showering or cooking could cause your windows to fog up. There are a few things you could do to lower the chances of this happening, including:

Give your windows room to "breathe" by opening curtains or blinds a little.
Use a fan to keep air circulating.
If you use a humidifier, consider turning it down or off. If you have enough moisture to fog up windows, it may be set too high.
Make sure you have exhaust fans in steamy areas in your home, and that you use them when you are generating steam by showering or cooking.

People Also Ask...

How Do Double Pane Windows Get Foggy?

If you notice condensation between the panes of your double pane windows or doors, it's a sign that the windows are not sealed properly. Moisture has got between the panes, and they window will need to be assessed and repaired or replaced. There is no other way to remove the condensation between the panes.

Why Didn't My Single Pane Windows Get Foggy?

When you have double or triple pane windows, the atmosphere between the panes and outside is actually different to the atmosphere inside your home. So while your home might not be too warm or humid, if moisture has got between the panes, they could still become foggy. They are also designed to be an insulator, so even if your home is humid, you might not have fog on the inside of your windows when you have double or triple glazing.

Are Foggy Windows a Major Problem?

That really depends where the condensation is, and how much there is. If there is enough moisture to drip down, it could eventually lead to moisture related problems.

What Does Condensation on a House Window Mean?

If there is condensation on the outside of your windows, it means that it the air outside has fallen below the dew point, and it's fairly humid outside.

If you have condensation inside your windows, it usually means that your home is hotter and more humid than it is outside, so moisture lands, cools and condenses on your windows.

If there is condensation between panes on double glazed doors and windows, it probably means that the windows are not properly sealed and should be inspected and repaired or replaced.

Condensation on windows is usually not a problem - but it really does depend where it is happening. Take a closer look the next time you notice this happening, and if it's anywhere other than between double glazing panes, you can probably relax and just wipe up any moisture you find!