Fog or condensation between window panes
Urgency
1/5
Honest verdict: this one's worth a pro$200–$700 per windowTypical repair cost
Likely causes, most common first
- Failed insulated-glass seal — the unit lost its gas fill and now breathes moist air
- Age: seals commonly fail at 15–25 years
- (Condensation on the INSIDE surface is different: that's indoor humidity, not seal failure)
Do this right now
- Confirm the fog is between panes (can't be wiped from either side)
- Count affected windows — same-age windows fail in waves, which changes the replace-vs-repair math
DIY or call a pro?
Options in order of cost: replace just the glass unit (IGU) in a sound frame, or the full window when frames are also tired. Same-size glass swaps usually need no permit — we'll price both paths honestly.
Planning this project?
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