How to Get Rid of Fog in Your Windows

As much as it’d be nice to blame the weather outside for the fog in your windows, it’s not always at fault. In fact, the fog on your glass windowpanes is often an indication that something is awry with the window unit.

It depends on what kind of windows your home is outfitted with and how long ago they were installed. Newer windows rarely fog, so if they do, it really could be the fault of weather. Older windows—or cheap ones—will fog as a sign that something is wrong. What’s the matter with them and how do you eliminate the fog?

Window Condensation

A Bad Seal

More often than not, the fog accumulating on your windows can be blamed on a bad or broken seal. Nearly all modern windows are manufactured with insulating gas trapped between the panes. Gas-filled windows are available even on low-cost models. The gasses in the window unit used to better insulate your home are argon or krypton and greatly increase the window’s energy efficiency, helping regulate the home’s internal temperature.

The seal is an essential in keeping the gas contained. However, it’s prone to deteriorating with time, expose to the elements like water and excess heat, and can break or become worn. Fog occurs when the seal is bad or is broken in the insulated glass unit (IGU).

Check your seal after a heavy storm, one that brings plenty of rainfall. This is a surefire way to tell if your windows are struggling to expel water and are taking on water damage. The seal won’t hold up well to prolonged exposure to moisture, just like anything else. You’ll notice water buildup in the window unit if this is the case as well as the fog that’s spreading across the panes.

Heat can also cause fog to occur. Warm air expands, and with a double-pane window, there is air lingering between the glass panes that gives to this effect, which in turn could stretch the window’s seal. While windows are manufactured to deal with the effect of heat expansion, it’s prolonged heat and sunlight exposure that really can damage the seal in the long-term.

An old seal is another reason why you’re seeing fog in your windows. Ask yourself when the windows were installed. If it’s been decades, the seal is certainly deteriorating and it’s about time to be replacing the window units in their entirety anyway. Getting new windows will dramatically increase your home’s energy efficiency as well as eliminating the issue of fog.

Bad Window Installation

Broken Glass

Broken windowpanes are an obvious problem and the reason why you’re seeing condensation and fog between panes. It doesn’t have to be a clear break of glass either, even a small crack in the glass can be the cause of fog in your windows.

You can replace the glass yourself if you’re handy enough or better yet, you can have a professional do the job. Remember, when a window unit isn’t installed correctly, you’re going to continue to see fog and experience leaks and drafts.

Preventing Fog in Your Windows

Of course, the best and most reliable way to fix your foggy windows is to replace them. Constant fogging is a sign that it’s time to do so anyway. This is especially true if your windows are decades old and don’t have the modern IGU that makes it more energy efficient. A window upgrade will save you money on your energy bills, increase your resale value, and get rid of that pesky fog once and for all.

If your windows aren’t old enough to justify a full replacement, then consider just replacing their IGUs. This is where the seal is located that is most likely at fault for causing fog on the windowpanes. There may be a catch here, however. It’s technically cheaper to just replace the IGUs to rid yourself of the fog, but it’s more cost-effective to actually replace the window unit. You see, there are many parts of an IGU, which makes its replacement a complicated and labor-intensive process. Thinking long-term, you might as well get new windows if it’s fogging up that badly.

A temporary solution involves using defogging spray, although it’s simply masking the problem at hand: poor insulation. You can also use common household products to prevent fogging like shaving cream, but again, these tricks only work for some time.

Board Up Windows

High-Quality Windows Won’t Fog

Windows that are installed correctly and are energy efficient will resolve your issues with fogging. High-quality, energy-efficient windows are designed to negate condensation and fogging as best as possible, so if you’re experiencing fog in your windows, then it’s time for an upgrade.

It could also mean that your windows weren’t installed correctly in the first place. It’s extremely imperative that you thoroughly vet your contractors and hire professionals who are trained in installing windows. A window that’s not installed right will leak, draft, and most definitely fog because of the glass and seal failures.

Replace Those Old Windows

Replacing your windows doesn’t have to be a nightmare that it’s so often made out to be. When you learn about options like vinyl windows, replacements start to not only seem like a good idea, but a smart investment for your home.

If you have fog in your windows, and it’s time for replacement windows, Feldco has you covered. We’ve been serving the Midwest for almost 50 years and have earned the title of America’s #1 window and door company.

We have many showrooms across the Midwest and that’s why we have helped over 500,000 homeowners with their home improvement goals. Speak to a product specialist and get a free quote today.

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