Window Seal Failure is More Common than You Think

For a window to work properly, it should have a tight seal between the window panes. The window should also be easy to open and close. When shut, air shouldn’t be seeping through, but homeowners are often surprised to learn that window seal failure is too common.

In Wisconsin, getting out the tape and plastic is a needless but “time-honored tradition.” Many Midwesterners worry that cold weather will leak into their homes without the extra insulation. The truth is, if you have reliable, working windows, they should be free from leaks—there’s no need to get out the tape and plastic come October.

Another common sign that you’re experiencing window seal failure is monitoring how consistent the temperature stays in your home. Do you need to wear socks or a sweater? If you’re living in a drafty house, there’s no reason to settle. Learn the signs of window seal failure in case it’s time to consider replacement windows for your home.

Window Seals Can Fail at Any Age

We’ve seen window seal failure in homes under ten years old! It’s always sad when this happens because homeowners don’t expect it. When buying a newly built home, they think it will last years before needing repairs.

Unfortunately, contractors often cut corners and choose cheaper windows when they do a major development. They may even get a special deal on bottom-of-the-line windows. At Weather Tight, we’ve noticed that when one home in the subdivision experiences window seal failure, it seems to start an unfortunate trend.

Of course, window seal failure is also a common problem in older homes. As windows age, the wooden frame can expand and contract. Panes of glass can become loose, and water, sun, and temperature changes can damage the seal over time. Eventually, even the sturdiest homes will start to see drafts, no matter the type of windows.

But when someone buys an older home, the state of the windows is often a consideration. Homebuyers expect that an older home will need a few updates and renovations. After all, older windows often show their age. It’s the brand-new or recently built homes where window seal failure comes as a shock. Even with a quality window, an improper installation can cause drafty windows and higher energy bills.

Check out this video below from Tod & Todd that shows seal failure in a 10-year-old home.


Window seal failure is much more common than you would think. Be sure to familiarize yourself with the signs so you know what to watch for in your windows.

Learn the 5 Signs of Window Seal Failure to Watch For

Wondering if window replacement is in your near future? There are a few signs of seal failure that you should keep an eye on.

1. Foggy Windows

Foggy windows aren’t to be confused with normal window condensation. Every living space has fluctuating humidity. Even newer homes with special HVAC measures in place may still experience regular moisture changes due to the temperature difference between indoors and out. When we shower, work out, or cook in our home, we might see even more window condensation. Pets, plants, and people can also contribute to moist air, which causes this normal issue.

Window condensation isn’t a sign of window seal failure, but foggy moisture buildup in between glass panes, on the other hand, indicates a broken window seal. When seals are working correctly, the inert gasses acting as insulation in most modern windows stay inside. The insulated glass unit appears clear. When the seal is broken, moisture gets trapped between the panes. Windows appear foggy, cloudy, or impossible to clean. The answer to foggy window glass is usually replacement.

2. Drafts Around the Windows

The best way to find a failed seal is to try the wet hand test around the entire window. A window with a working seal shouldn’t give off any drafty air. When holding your dampened hand up to the windowpane, you shouldn’t feel outside air drafting in. Even when the weather outside is frightful, your windows should keep the indoors warm (and delightful).

You also shouldn’t see ice or frost inside your windows. Hardware may get very cold; often made of metal, it conducts temperature and will get chilly with constant exposure to icy conditions. However, glass windowpanes and the surrounding frames should stay frost-free, and even if they feel cold, they shouldn’t get icy indoors.


A woman sits on a window ledge, wearily looking out the bright windows. She's wrapped in a plaid blanket, wearing long sleeves, pants, and warm socks, and holding a mug of tea.

3. Irregular Temperatures

Another sign that you should consider window replacement is the ambient temperature of your home. Do you get so cold indoors that you need to put on extra socks, a sweater, or wear a hat? Does your home get so cold that it feels uncomfortable? How is your home’s energy efficiency? Do you feel like your heating bills increase each month?

You should always feel just right inside your home—not too cold and not too hot. When you set your thermostat, you should get consistency throughout the building. If your home is adequately ventilated and has good insulation, temperatures shouldn’t fluctuate. If they do, it could be a sign that your windows aren’t doing their job very well. Many homeowners can’t believe the way energy-efficient replacement windows improve their comfort.

4. Damaged Window Frames

Take a look at the frame and caulking around your window. Is it black from mold or mildew? Is the paint bubbled, chipped, or peeling? Do you see signs of weather damage from the sun or rain? What about wood rot? Window frames often show their age and are among the first ways to spot damage from window seal failure. A damaged frame can lead to a broken seal.

When we assess your windows for replacement, we’ll look at the window frame and the surrounding hardware. Depending on the condition of the area surrounding your window, we may recommend a full-frame replacement versus a pocket replacement. To get the best seal possible, you may also have to replace the frame. When we do a full-frame replacement, we can pinpoint any other issues like pests or water damage.

5. Windows that Are Hard to Open and Close

Finally, properly working windows shouldn’t be challenging to open or close. They should be secure, but when you unlock the window, you should open it with ease. You should never have to dangerously “prop” a window open or jam it closed with a broom handle for security. Windows that are hard to open and close can be a safety hazard for anyone, including children and pets. If you have difficulty opening a window, it’s one of the common signs of window seal failure.

Replacement windows from Weather Tight are easy to open and close and lock securely. You can open the window indoors for easy cleaning. When you close the window and easily push the lock closed, your window will be sealed tightly and safely!

Windows keep your home comfortable and beautiful, connecting you to the outside world. Brighten up your home and eliminate drafts with beautiful replacement windows from Weather Tight. New windows can help you avoid higher energy costs and increase your comfort and pride in your home.

No matter your home’s age, if you suspect window seal failure, contact us today for an assessment and free estimate. Let us show you how affordable and comfortable new windows can be!