Broken Window Seals? A few things you need to know.

July 5, 2023

You know what's annoying. Broken seals on double or triple paned windows. They cause a build up of moisture in between the glass, that neither you nor I can get to. And the problem is that when moisture or humidity builds up inside the glass, it becomes foggy and prevents you from getting those clear views that we often enjoy from clean windows.

Most modern windows are created out of two pieces of glass with dead space in the middle that insulates your home. The glass's edge is sealed with caulking that keep out any moisture, and often times the interior of the pane is filled with an inert gas that acts as "insulation". When this rubber breaks, you oftentimes end up with dirty windows AND the gas inside escapes, meaning your windows won't keep your home as warm or cold as they should.

What breaks the seals?

Visual condensation and even warped glass (where the image on the other side is slightly distorted) are some pretty obvious signs of what's going on. The reason a windows seal may fail can vary, but typically it has to do with one of three things:

  • Pressure put on the glass that breaks down the rubber seals. This can come from several different sources, including wind, faulty installation, and even from a newly built home where the foundation is continuing to settle.
  • Heat, as this can expand the glass, stretching and cracking seals, or simply melts the rubber enough to introduce a few small gaps. Interestingly enough, most of the homes I clean often have windows with broken seals on the West and South sides (the ones seeing the most sun, and of course, heat).
  • Chemicals can also cause damage to the sealant around windows. Paint stripper is oftentimes a perpetrator, especially if the homes been repainted in the past.

Can you repair or prevent broken window seals?

So what can you do about faulty seals and foggy panes? We often suggest two courses of action. One, prevent it from happening in the first place, and two, replacing the pane.

You can keep seals from breaking if you regularly check your windows, we normally suggest doing it once before winter. If you notice any gaps, caulk them to prevent moisture from entering. You should also keep track of your window warranties (and avoid putting tint or film on the windows if it voids them) so if anything does happen, you can replace them for little to no cost.

As far replacing windows, a lot of the time this can be done without replacing the entire unit, just single panes or IGU's (Insulated Glass Unit). With a warranty, the most you'll have to pay is labor costs, without it, you're looking at paying around $100-$600 per IGU.

​Finally, I have heard that you can have a pro come out and drill through the glass, add a product that dries up any moisture, and try to reseal the window, although I'm not familiar with any companies that currently do it.

Regardless, I hope this post has helped you with those pesky window panes that always seem to be a little foggy or off!


​Wes Kolste