Sold under many names
Foggy window
Haze or moisture trapped between the panes — a sign the sealed glass unit's seal has failed and its insulating gas has leaked out.
What it means for you
The good news: it's usually the glass unit that failed, not the whole window, so you can often replace just the IGU for far less than a new window.
Where you'll see it
You'll see it on the glass; a good pro will tell you whether it's a glass-only fix.
Also sold as: failed seal · blown IGU
Related terms
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