In Prestwich, 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
- Splits, blisters or lifted edges in the roof covering by the kerb
- Ponding on the roof next to the lantern
What usually causes it?
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 Prestwich 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.
In built-up areas, access is often the hardest part of the job — through the house, over a neighbour's roof, or with parking restrictions. We plan access in advance and price any tower or scaffold into the quote.
Prestwich is around 4 miles from Manchester, and both are within our Greater Manchester coverage.
If you're just outside Prestwich, we also cover Whitefield (1 mile), Radcliffe (3 miles), Salford (3 miles).
How much should it cost?
Most flat roof junction and flashing repairs jobs come in between £245 and £695 ex VAT (£294–£834 including 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?
Most lantern repairs in England need no approval at all. Where a job turns into a replacement, the Building Regulations 2010 apply and we confirm how the work will be signed off before we start. 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 Prestwich: questions
How do I get a price for flat roof junction and flashing repairs in Prestwich?
Send a few photos of the lantern and the problem, with your Prestwich 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 Prestwich?
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.
What does a junction repair cost?
Usually £245–£695 ex VAT, confirmed in writing before work starts.
Can you repair a GRP roof without it showing?
Repairs are colour-matched as closely as possible, but new topcoat next to weathered topcoat can look slightly different at first.
Other lantern repairs in Prestwich
- Cracked lantern glass replacement in Prestwich
- Opening vent and actuator repairs in Prestwich
- Roof lantern respraying in Prestwich
- Leak investigation and inspection in Prestwich
- Urgent leak make-safe in Prestwich
- Orangery lantern repairs in Prestwich
Flat roof junction and flashing repairs near Prestwich
More about flat roof junction and flashing repairs · All roof lantern repairs in Prestwich