The junction where the flat roof covering meets the lantern kerb is a weak point on many extensions. Send photos from Risca (NP11) and we'll tell you which it is — with the price agreed in writing before any work.

What you might be seeing
- Splits, blisters or lifted edges in the roof covering by the kerb
- 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.
Roof lanterns in Risca
Western and upland parts of the UK get more rain and more wind-driven rain than the east, and that's what finds weak cappings and blocked eaves first. Lanterns here benefit from a check of the bars on the most exposed face and a clear eaves channel before winter.
From Newport, Gwent to Risca is roughly 5 miles — all part of the Gwent area we cover.
Neighbouring places we cover include Newport, Gwent (5 miles), Cwmbran (5 miles), Caerphilly (6 miles).
What should you expect to pay in Risca?
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 Wales?
Straightforward repairs — resealing, gaskets, cappings, eaves and like-for-like parts — don't normally need building regulations approval in Wales. Replacing the whole lantern or enlarging the opening is different and falls under the Building Regulations 2010 (as applied in Wales); we confirm in writing which route applies before any replacement. Listed buildings in Wales need listed building consent from the local planning authority for alterations, with Cadw guidance on historic buildings; check with the council 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.
Flat roof junction and flashing repairs in Risca: questions
Do you need to visit to price flat roof junction and flashing repairs?
Not always. Clear photos are often enough for a guide price. Where the cause isn't obvious, a visit to inspect and water-test is charged from £145 ex VAT, confirmed before we come.
Can you repair a lantern someone else installed in Risca?
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 Risca
- Roof lantern resealing in Risca
- Timber roof lantern repairs in Risca
- uPVC roof lantern repairs in Risca
- Roof lantern respraying in Risca
- Roof lantern replacement in Risca
- Commercial roof lantern repairs in Risca
Flat roof junction and flashing repairs near Risca
More about flat roof junction and flashing repairs · All roof lantern repairs in Risca