If you see fog, haze or water spots between the two panes of glass, the window’s seal has failed. You can’t wipe it away, and it won’t fix itself. It’s one of the most common problems we see in Salt Lake Valley homes built in the 1990s and 2000s.
Why Seals Fail in Utah
Double-pane windows are sealed units filled with insulating gas. Utah’s big daily temperature swings make the glass expand and contract, and the strong sun bakes the seals. After 15 to 25 years, many seals give out. Once moist air gets in, the gas leaks out and the window insulates much like a single pane.
Your Three Options
| Option | When it makes sense | Watch out for |
|---|---|---|
| Defogging service | Only a cosmetic fix is wanted | Clears the view but doesn’t restore the insulating gas |
| Replace the glass unit only | 1–2 foggy windows; frames and sashes in good shape | Matching older glass sizes; frame may fail soon after |
| Replace the whole window | Several foggy windows, drafts, sticking sashes, or older frames | Higher cost, but solves everything at once |
Check the Warranty First
Look for etching or a label in a corner of the glass with the brand and date, then contact the manufacturer or your original installer. Many vinyl windows carry a seal warranty, and replacement glass may be covered.
When Whole-Window Replacement Is the Better Value
If several windows are fogging, more will follow, because they are the same age and were built the same way. Replacing them together costs less per window than one at a time, and new Energy Star windows also fix drafts and hard-to-open sliders. See what window replacement costs in Salt Lake City.
Want a second opinion? We’ll check your windows during a free consultation and tell you honestly whether glass-only replacement is enough. Window replacement · Builder price program
Foggy Window FAQ
Why are my windows foggy between the panes?
The seal around the double-pane glass unit has failed. Moist air gets between the panes and condenses, and the insulating gas has usually leaked out.
Can foggy windows be fixed without replacing them?
Sometimes the glass unit alone can be replaced if the frame and sash are in good shape. Defogging services can clear the view but do not restore the insulating gas.
Is a foggy window covered by warranty?
Often, if it is within the manufacturer’s seal warranty. Check the label or etching on the glass corner for the brand and date, and contact the manufacturer or installer.