If a roof lantern pane looks cloudy or wet between the two layers of glass, the sealed unit has failed and moisture has got inside. Send photos from Dumbarton (G82) and we'll tell you which it is — with the price agreed in writing before any work.

Is it time for misted glass unit replacement?
- Fog, droplets or white bloom between the panes
- Misting that comes and goes with the weather
- Water marks or tide lines inside the unit
Why it happens
Edge seal failure
Every sealed unit has an edge seal and desiccant. Once the seal fails, humid air gets in and the desiccant saturates.
Water sitting on the edge
If the unit's edge sits in water because the eaves don't drain, the seal fails sooner.
About Dumbarton and the G82 area
Wind-driven rain is the real test of a roof lantern, and the wetter west sees plenty of it. Leaks that appear only in a storm from one direction usually point to the cappings or eaves on that face — a useful clue when you send us photos.
Urban grime and traffic film dull glass and frames quickly; a clean and seal check makes a tired lantern look and perform much better.
Dumbarton is around 13 miles from Glasgow, and both are within our Glasgow and Clyde coverage.
If you're just outside Dumbarton, we also cover Clydebank (7 miles), Greenock (7 miles), Helensburgh (7 miles).
How much should it cost?
Typical range: £245–£595 ex VAT, which is £294–£714 with VAT, per glass unit. Towers or scaffold, where needed, are priced into the quote. Your fixed price is confirmed in writing before any work starts.
Do you need permission in Scotland?
Most lantern repairs in Scotland need no approval at all. Where a job turns into a replacement, the Building (Scotland) Regulations 2004 apply and we confirm how the work will be signed off before we start. Listed buildings in Scotland need listed building consent from the planning authority for alterations, with Historic Environment Scotland guidance; check before changing a lantern on a listed property.
How does it work?
- Send photosWhatsApp or upload a few photos and tell us when it leaks.
- Guide priceWe reply with a guide price and whether a visit is needed.
- Fixed price in writingYou approve the price and the date before anything starts.
- Repair and testWe fix what's failed, water-test where it matters, and send photos.
Misted glass unit replacement in Dumbarton: questions
Do you need to visit to price misted glass unit replacement?
Not always. Clear photos are often enough for a guide price. Where the cause isn't obvious, a visit to inspect and water-test is charged from £145 ex VAT, confirmed before we come.
Which places near Dumbarton do you cover?
As well as Dumbarton, we cover nearby Clydebank, Greenock, Helensburgh, Johnstone and the rest of Glasgow and Clyde.
How much does a misted lantern unit cost to replace?
Usually £245–£595 ex VAT per unit depending on size, glass spec and access, confirmed in writing before work starts.
Will the new pane match the others?
We match tint and coatings as closely as possible; a new unit can look very slightly clearer than older neighbours.
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Misted glass unit replacement near Dumbarton
More about misted glass unit replacement · All roof lantern repairs in Dumbarton