In St Austell, as everywhere, a roof lantern leak is almost always a failed seal, a lifted capping, blocked eaves drainage or a problem where the kerb meets the flat roof — not a failed lantern. Send photos and we'll tell you what we think has failed.

Signs you need roof lantern leak repairs
- Drips from a glazing bar or the eaves beam when it rains
- Water running down the inside face of the glass
- A leak that only appears in wind-driven rain from one direction
What usually causes it?
Failed silicone or glazing tape
UV and thermal movement break down the seal between capping, gasket and glass. Once a gap opens, water tracks along the bar and drops at the lowest point.
Lifted or misaligned cappings
Top cappings clip or screw over each glazing bar. If one has lifted, been knocked or was never seated, rain gets straight under it.
Covering St Austell and nearby
Damp, mild winters keep moss and algae growing on flat roofs and lantern frames, which holds water against seals and blocks weep slots. Regular clearing makes a real difference in wetter areas.
Coastal wind drives rain hard against lanterns, so cappings and ridge seals on the seaward face take the most punishment.
From Truro to St Austell is roughly 13 miles — all part of the Cornwall area we cover.
Neighbouring places we cover include Bodmin (9 miles), Truro (13 miles), Newquay (14 miles).
How much should it cost?
Guide price for roof lantern leak repairs: £195–£595 ex VAT (£234–£714 inc VAT), per lantern. 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 England?
In England, 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 Regulations 2010, so we set out the route in writing first. Listed buildings need listed building consent from the local council for alterations, and conservation areas can have extra controls; like-for-like repairs are treated differently from changes, so check with the council's conservation officer first.
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.
Roof lantern leak repairs in St Austell: questions
How do I get a price for roof lantern leak repairs in St Austell?
Send a few photos of the lantern and the problem, with your St Austell postcode. We'll reply with a guide price and tell you whether a visit is needed before we can fix the price.
Can you repair a lantern someone else installed in St Austell?
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 much does a roof lantern leak repair cost?
Most leak repairs fall between £195 and £595 ex VAT for a standard lantern with ladder access. The fixed price is confirmed in writing before any work starts.
Will you show me what was wrong?
Yes. We photograph the failed detail and the finished repair and send them to you with the invoice.
Other lantern repairs in St Austell
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