In Coulsdon, 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.
Signs you need flat roof junction and flashing repairs
- Leak near the lantern but not from the frame
- Missing or loose edge trims and flashings
- Ponding on the roof next to the lantern
Why it happens
Cracked GRP
Fibreglass roofs can crack at the kerb corner where movement concentrates.
Missing trims
Without a trim or flashing to protect the top edge, water gets in behind the membrane.
Covering Coulsdon and nearby
Drier, sunnier parts of the UK are kinder to seals than the wet west, but strong sun ages sealant, gaskets and plastic end caps, and south- or west-facing lanterns can make rooms very warm. Solar control glass and an opening vent help.
Across London, many lanterns sit on rear extensions with access only through the house, so we protect floors and plan the work to keep time indoors to a minimum. Parking and any permits are factored into the quote.
From Westminster to Coulsdon is roughly 12 miles — all part of the Greater London area we cover.
We also cover nearby Purley (2 miles), Banstead (3 miles), Wallington (3 miles).
What should you expect to pay in Coulsdon?
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 Coulsdon: questions
Can you repair a lantern someone else installed in Coulsdon?
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.
Which places near Coulsdon do you cover?
As well as Coulsdon, we cover nearby Purley, Banstead, Wallington, Sutton and the rest of Greater London.
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 Coulsdon
- Misted glass unit replacement in Coulsdon
- Cracked lantern glass replacement in Coulsdon
- Solar control and self-cleaning glass upgrades in Coulsdon
- Condensation diagnosis and fixes in Coulsdon
- Urgent leak make-safe in Coulsdon
- Commercial roof lantern repairs in Coulsdon
Flat roof junction and flashing repairs near Coulsdon
More about flat roof junction and flashing repairs · All roof lantern repairs in Coulsdon