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 St Andrews (KY16) and we'll tell you which it is — with the price agreed in writing before any work.

Signs you need misted glass unit replacement
- One pane looks hazier than the others
- Misting that comes and goes with the weather
- Water marks or tide lines inside the unit
What usually causes it?
Edge seal failure
Every sealed unit has an edge seal and desiccant. Once the seal fails, humid air gets in and the desiccant saturates.
Movement and age
Thermal movement and age wear the seal; units at the bottom of the lantern often go first.
Roof lanterns in St Andrews
Colder winters mean more frosty mornings, and a roof lantern is often the coldest surface in a warm kitchen — so condensation is as common as genuine leaks. We check which you've got before quoting.
Near the coast, salt in the air is hard on aluminium finishes and fixings; washing the frame occasionally and touching in chips keeps corrosion away.
St Andrews is around 31 miles from Dunfermline, and both are within our Fife coverage.
Close by, we also cover Cupar (8 miles), Dundee (11 miles), Carnoustie (12 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?
In Scotland, like-for-like repairs to a roof lantern don't usually involve building control. A full replacement or a bigger opening is controlled under the Building (Scotland) Regulations 2004, so we set out the route in writing first. 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 St Andrews: questions
Do you cover St Andrews?
Yes. We cover St Andrews, including the KY16 postcode area, as part of Fife. Send photos by WhatsApp or the form for a free guide price, and we'll confirm the fixed price in writing before any work starts.
Can you repair a lantern someone else installed in St Andrews?
Yes. We repair lanterns whoever fitted them. If yours is still under the installer's warranty, contact them first so you don't affect it.
How long does a replacement unit take?
Units are made to measure, so there's a lead time between measuring and fitting. Fitting itself is usually a short visit.
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.
Other lantern repairs in St Andrews
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Misted glass unit replacement near St Andrews
More about misted glass unit replacement · All roof lantern repairs in St Andrews