I have double pane gas filled vinyl windows that are approximately 10 years old that recently starting condensation around the edges of the glass. I've done some basic caulking around a few of the windows but it didn't' seem to help. Should I caulk around where the glass meets the frame? Any tips to prevent the condensation and (likely) drafts?

See pictures below (note condensation is on the exterior of the window not inside):

https://www.dropbox.com/s/ud82e7jqsgtz5o9/IMG_20151228_094959.jpg?dl=0 https://www.dropbox.com/s/f73s61x8edds8tm/IMG_20151228_094945.jpg?dl=0 https://www.dropbox.com/s/dwl5u2bpzpwil22/IMG_20151228_094934.jpg?dl=0

1 Answer 1


Condensation appears to be on the inside of the window.

After 10 years, the seals have failed. They are no longer "gas-filled" - they just have air in there, and the air in there has water in it, which condensed when they are cold. The only way to fix this is to replace the double-pane unit. It's remotely possible that if your window manufacturer was optimistic this MIGHT be a covered failure (they would pay for or supply the replacement panes under warranty), but it often is not.

  • Thanks for the reply. The condensation is definitely on the outside of the window however.
    – JavaKungFu
    Commented Dec 28, 2015 at 15:08
  • I think Ecnerwal means that the condensation occurs between the panes of glass. In this case, (s)he's right. Those sealed units are not serviceable.
    – isherwood
    Commented Dec 28, 2015 at 16:03
  • It looks like it is between the panes too. I have not seen condensation like that on the outside of a window. It is hard to tell just by looking. I would remove the insect screen and touch it. Condensation on the outside of a piece of insulated glass usually forms on the room side of a window, not the exterior side.
    – Jack
    Commented Dec 28, 2015 at 16:11
  • Sorry what I meant was that it's not in between the panes of glass, it's on the room side of the glass, so when I touch the window it is wet. So that means the window is bad?
    – JavaKungFu
    Commented Dec 28, 2015 at 17:17
  • 1
    The last picture in particular looks very much like it's both inside and in between. Likewise, the reduced insulation value (causing the inside to be cold enough to condense) suggests failure. If this behavior is new, and you have not just added some egregious source of moisture to the house (new fish-tank? Broken dryer vent or bathroom exhaust fan?) it strongly suggests double-pane unit failure.
    – Ecnerwal
    Commented Dec 28, 2015 at 17:29

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