If you have 10 foggy windows, IGU replacement at $300 each = $3,000. Full replacement could be $8,000+. You can see why glass replacement is appealing. Do not try to separate the glass panes yourself. A broken seal exposes the sharp edges of the spacer and glass. Moreover, if your window was made before 2000, the spacer may contain desiccant (silica gel) that is caustic. And if the unit ever had a lead-based coating? You’ll create a toxic dust.
This is almost as labor-intensive as full replacement and often fails again quickly. Most professionals won't offer this. Option 3: Glass Unit Replacement (The real fix) This is the gold standard. You keep your existing window frame (sash) but replace only the insulated glass unit. A glazier removes the old IGU, orders a new one custom-sized, and installs it. double paned window repair
| Repair Type | Average Cost per Window | Energy Savings Restored? | | --- | --- | --- | | Defogging | $60 – $100 | No | | IGU Replacement (glass only) | $200 – $400 | Yes | | Full window replacement | $600 – $1,200+ | Yes | If you have 10 foggy windows, IGU replacement