Foggy Window Glass Replacement Cost Guide (2026)
💰 Cost Breakdown
| Item | Low | Average | High |
|---|---|---|---|
| Standard IGU replacement (double-pane, average size) New sealed glass unit fabricated to size and installed in your existing sash. The default fix for seal failure. | $200 | $375 | $600 |
| Low-E / argon-filled IGU replacement Matches the energy performance of modern glass. Adds $50–$150 per unit over clear glass. | $275 | $450 | $700 |
| Large or specialty shapes (picture windows, arches) Oversized units, tempered glass, or non-rectangular shapes are custom fabrication and priced accordingly. | $400 | $800 | $1,500 |
| Full window replacement (insert, per window) New window unit set into the existing frame opening. The right call when frames, sashes, or hardware are also failing. | $600 | $1,000 | $1,500 |
| Defogging service (drill-and-vent) Drills the unit, clears the moisture, and installs vents. Improves appearance but does not restore insulating gas or the seal. | $75 | $135 | $250 |
Standard IGU replacement (double-pane, average size)
New sealed glass unit fabricated to size and installed in your existing sash. The default fix for seal failure.
Low-E / argon-filled IGU replacement
Matches the energy performance of modern glass. Adds $50–$150 per unit over clear glass.
Large or specialty shapes (picture windows, arches)
Oversized units, tempered glass, or non-rectangular shapes are custom fabrication and priced accordingly.
Full window replacement (insert, per window)
New window unit set into the existing frame opening. The right call when frames, sashes, or hardware are also failing.
Defogging service (drill-and-vent)
Drills the unit, clears the moisture, and installs vents. Improves appearance but does not restore insulating gas or the seal.
📊 Factors That Impact Cost
Glass size and type
High ImpactIGUs are priced by the square foot, with premiums for tempered glass (required near doors, floors, and tubs), laminated glass, and triple-pane construction.
Frame material and sash design
Medium ImpactVinyl and aluminum sashes usually open up easily for re-glazing. Some wood sashes and older designs take more labor to disassemble without damage.
Coatings and gas fill
Medium ImpactMatching existing Low-E coatings keeps the tint consistent across your windows. Argon fill adds modest cost and restores original energy performance.
Accessibility
Medium ImpactSecond-story exterior-glazed windows or units above stairwells add ladder and handling labor, especially for large heavy glass.
Number of windows done at once
Medium ImpactSeal failures cluster by age — windows installed together fail together. Per-window pricing drops meaningfully when several units are measured and replaced in one job.
💡 Money-Saving Tips
Quote glass-only replacement before full window replacement
Window replacement companies quote windows; glass shops quote glass. For fogged units in sound frames, the glass shop's number is usually a third to half the window company's number for the same visual result.
Batch all failed units into one order
One measuring visit, one fabrication order, and one install trip spread the fixed costs across every window. Walk the house with a flashlight and find every fogged unit before you book.
Check your window manufacturer's warranty first
Many IGUs carry 10- to 20-year seal warranties, and some are transferable from the previous homeowner. A covered unit may cost you only the install labor.
Skip defogging unless appearance is the only goal
Drill-and-vent services make the glass look better but leave you with a single-pane-performance window. If you will eventually replace the unit anyway, put the money there.