In Chelsea, as everywhere, the junction where the flat roof covering meets the lantern kerb is a weak point on many extensions. Send photos and we'll tell you what we think has failed.

What you might be seeing
- Leak near the lantern but not from the frame
- Missing or loose edge trims and flashings
- Ponding on the roof next to the lantern
Common causes we find
Unbonded membrane
EPDM or single-ply that has come away from the kerb lets water run behind it.
Missing trims
Without a trim or flashing to protect the top edge, water gets in behind the membrane.
Covering Chelsea and nearby
Sun and UV do more damage than rain on many lanterns here: brittle ridge caps, chalky finishes and hardened gaskets. They're cheap to replace before they let water in.
London's extensions are often tight to neighbouring walls and roofs. Where a repair needs access over a neighbour's property, we'll tell you in advance so you can arrange it.
Chelsea is around 2 miles from Westminster, and both are within our Greater London coverage.
If you're just outside Chelsea, we also cover Battersea (1 mile), Fulham (1 mile), Pimlico (1 mile).
What should you expect to pay in Chelsea?
Guide price for flat roof junction and flashing repairs: £245–£695 ex VAT (£294–£834 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.
Flat roof junction and flashing repairs in Chelsea: questions
Do you cover Chelsea?
Yes. We cover Chelsea, including the SW10 postcode area, as part of Greater London. 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.
How do I get a price for flat roof junction and flashing repairs in Chelsea?
Send a few photos of the lantern and the problem, with your Chelsea postcode. We'll reply with a guide price and tell you whether a visit is needed before we can fix the price.
Do you repair the whole flat roof?
We repair the area around the lantern. If the wider roof is failing we'll tell you and can quote, but we won't push a new roof if a local repair will do.
What does a junction repair cost?
Usually £245–£695 ex VAT, confirmed in writing before work starts.
Other lantern repairs in Chelsea
- Ridge and hip repairs in Chelsea
- Eaves beam and gutter repairs in Chelsea
- Misted glass unit replacement in Chelsea
- Cracked lantern glass replacement in Chelsea
- Opening vent and actuator repairs in Chelsea
- Commercial roof lantern repairs in Chelsea
Flat roof junction and flashing repairs near Chelsea
More about flat roof junction and flashing repairs · All roof lantern repairs in Chelsea