We carry out flat roof junction and flashing repairs in St Albans and across the AL1 area. The junction where the flat roof covering meets the lantern kerb is a weak point on many extensions.

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
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 St Albans and nearby
Leaf fall from garden trees is the most common cause of eaves overflow on suburban extensions. If your lantern sits near trees, clearing the eaves channel each autumn prevents a lot of drips.
Neighbouring places we cover include Harpenden (5 miles), Hatfield (5 miles), Hemel Hempstead (5 miles).
What should you expect to pay in St Albans?
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?
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 St Albans: 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 St Albans do you cover?
As well as St Albans, we cover nearby Harpenden, Hatfield, Hemel Hempstead, Welwyn Garden City and the rest of Hertfordshire.
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 St Albans
- Ridge and hip repairs in St Albans
- Eaves beam and gutter repairs in St Albans
- Misted glass unit replacement in St Albans
- Timber roof lantern repairs in St Albans
- Aluminium roof lantern repairs in St Albans
- Commercial roof lantern repairs in St Albans
Flat roof junction and flashing repairs near St Albans
More about flat roof junction and flashing repairs · All roof lantern repairs in St Albans