How to Deal With a Broken Window Seal

On modern, multi-pane windows, a broken window seal can be anything from an annoyance to a real security risk. Either way, once the window seal is broken, the window is no longer working as efficiently.

So what causes a broken window seal, how can you tell if you have one, and what can you do about it?

What causes a seal to break on residential windows?

The most common cause of seal breakage is simply fluctuations in temperature. Windows and their frames heat up and expand during the day and contract when the temperature drops at night. These changes, and the fact that seal material hardens over time, can cause that seal material to crack and fail.

However, other things can also cause your window seal to fail.

Natural disasters like earthquakes.
Extreme wind that impacts windows.
Settling of a home, and changes in the structure of the window frame.
The use of a heat gun or similar tool to remove cracked paint or residue from windows.

Essentially anything that causes the window pane stress or to move in a significant way can impact your window seal.

How can you tell if the seal on a window is broken?

There are several tell-tale signs of a broken window seal. Perhaps the most common symptom homeowners notice right away is condensation between the glass of the window. Because modern windows often have two or more panes with an inert gas between them for additional insulation, this is a sure sign the window seal is broken.

That fog may get worse or better with changes in humidity, but it won’t ever really go away.

But you can also tell if the view of the world outside is distorted. As the inert gas leaves the window through a broken seal, the window will often bend inward and warp or even crack. If your view through your window looks distorted, your window seal is likely broken.

How do you deal with a broken window seal?

There are only a few choices when it comes to dealing with a broken window seal. Each has their pros and cons.

You can ignore it, for a time.

Your window will not be as efficient, but as long as the window pane does not crack or distort too much, you can choose to live with it short term. Unfortunately, this is not really a solution, as eventually, you will have to do something to repair the window.

Order a new IGU.

The panes are called an insulated glass unit, or IGU. With the model and size of your window, you can order a new IGU from the window manufacturer. Even if you don’t have this information, you can have a glass company come out, measure or remove the IGU, and have a custom one made to replace it.

Check the warranty.

In some cases, the window seal will be under warranty. Depending on who made the windows that warranty can last a few years, or in some cases as many as 15 years. Do keep in mind that the warranty is only in effect if the seal is broken because it failed. If other factors unrelated to the window are determined to be the cause, you could still be on the hook for the bill.

Replace the window.

The other option you have depending on the age of the window is to replace the entire window unit itself. When should you do this? If the frame is starting to wear, the paint is cracking, chipping, or fading it could be time to replace the window anyway. You can start off with a new warranty and new, more efficient components.

Which answer is right for you? Consult a licensed contractor and window installation specialist, and they can advise you on the best course of action.

Can you fix a broken window seal?

The short answer is no, you cannot. There are options, like a window defogging. This is when a company comes out and drills a small hole in the outer window pane. They then inject a chemical that eliminates condensation before applying a vacuum to suck as much air as possible out of the area between the windows. They will then seal the hole.

The problem with this method is that it is impossible to guarantee results or how long they will last. After all, if the seal is still broken, the window will fog again the next time there is a change in temperature and humidity. That could happen as quickly as the next day, and this service can cost as much as $100.

Once a seal is broken, the only way it can be “fixed” is for the IGU or the window unit to be replaced.

If you know or suspect you have a broken window seal, replacing the IGU or the window itself is always the best option. Any other efforts are just temporary, as replacement will eventually become necessary. Contact a window installer as soon as possible, so there is no opportunity for the problem to get worse.