In Northwich, 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
Why it happens
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.
About Northwich and the CW9 area
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.
Northwich is around 16 miles from Chester, and both are within our Cheshire coverage.
Close by, we also cover Winsford (5 miles), Warrington (10 miles), Runcorn (10 miles).
How much should it cost?
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?
Straightforward repairs — resealing, gaskets, cappings, eaves and like-for-like parts — don't normally need building regulations approval in England. Replacing the whole lantern or enlarging the opening is different and falls under the Building Regulations 2010; we confirm in writing which route applies before any replacement. 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 Northwich: 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.
Which places near Northwich do you cover?
As well as Northwich, we cover nearby Winsford, Warrington, Runcorn, Widnes and the rest of Cheshire.
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 Northwich
- Roof lantern leak repairs in Northwich
- Roof lantern resealing in Northwich
- Upstand and kerb repairs in Northwich
- Cracked lantern glass replacement in Northwich
- Cleaning and maintenance in Northwich
- Orangery lantern repairs in Northwich
Flat roof junction and flashing repairs near Northwich
More about flat roof junction and flashing repairs · All roof lantern repairs in Northwich