Misted Double Glazing Repair in Bristol
Cloudy, streaky, or permanently misted glass between the panes means the sealed unit has failed. It won't clear on its own and it can't be resealed — but you don't need a new window. We replace the glass unit only; the frame stays.
Family-run Bristol business · 20 years trade experience · Send us an enquiry with photos and we'll get back to you
Signs your double-glazed unit has failed
- A permanent cloudy or misty appearance between the panes — not on the surface
- Streaky marks or tide lines inside the unit that don't wipe off
- Condensation that appears between the panes in cold or damp weather
- The glass looks clear in warm dry weather but mists up when it's cold — the seal is on its way out
Why does double glazing go misty?
A double-glazed unit is two panes bonded together with a hermetic seal, enclosing a layer of gas (usually argon) between them. The seal keeps moisture out and maintains thermal performance.
Over time — typically 15–25 years, sometimes sooner on south-facing windows — the seal perishes. Once it fails, moisture gets between the panes. It can't escape, so it condenses and creates the permanent cloudy appearance.
The misting cannot be cleaned off and the seal cannot be repaired. The only fix is to replace the sealed unit.
What we do — and what we don't
The frame and the glass are separate. When the sealed unit fails, the frame is almost always fine — it just needs a new glass unit. We:
- Visit to measure the failed unit precisely
- Order a replacement sealed unit to the exact size (typically 5–7 working days)
- Return to remove the old unit, fit the new one, and refit the beading
- Test the finished result — a properly sealed, thermally efficient pane
We do not replace the frame unless it has failed independently — that would be an unnecessary cost.
Sealed units are manufactured to measure, so there is a lead time. From your call to a finished clear window, most jobs are completed in 7–10 days. The fitting appointment itself takes 30–60 minutes per unit.
What does it cost?
Replacing a sealed unit costs a fraction of replacing the whole window. The frame stays — you're paying for glass and labour only.
| Option | Typical cost (+ VAT) |
|---|---|
| Sealed unit replacement (glass only) | From £165 |
| Full window replacement (frame + glass) | From £600 |
We confirm the price after measuring — larger or non-standard units cost more, but the price is always agreed before anything is ordered.
Misted window? Send us a photo.
We can usually tell from a photo whether it's a failed sealed unit and give you a rough price before visiting. Get a free quote below. If the glass is in a door, see door glass replacement — toughened safety glass is required.
Part of our full glass replacement service in Bristol.
Get a Free Quote
Describe the problem and add photos if you have them. We'll reply with a diagnosis and price — usually within a few hours.
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