In Thamesmead, as everywhere, a roof lantern leak is almost always a failed seal, a lifted capping, blocked eaves drainage or a problem where the kerb meets the flat roof — not a failed lantern. Send photos and we'll tell you what we think has failed.

Signs you need roof lantern leak repairs
- Drips from a glazing bar or the eaves beam when it rains
- Water running down the inside face of the glass
- A leak that only appears in wind-driven rain from one direction
What usually causes it?
Lifted or misaligned cappings
Top cappings clip or screw over each glazing bar. If one has lifted, been knocked or was never seated, rain gets straight under it.
Blocked eaves drainage
Most lanterns collect water in a channel inside the eaves beam and let it out through weep slots. Leaves, moss and grit block the slots and the channel overflows indoors.
Roof lanterns in Thamesmead
Even in drier areas, one heavy downpour with blocked eaves is enough to overflow a lantern indoors. Clearing the eaves channel is the simplest prevention there is.
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.
Thamesmead is around 11 miles from Westminster, and both are within our Greater London coverage.
We also cover nearby Barking (3 miles), Welling (3 miles), Becontree (3 miles).
What should you expect to pay in Thamesmead?
Guide price for roof lantern leak repairs: £195–£595 ex VAT (£234–£714 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.
Roof lantern leak repairs in Thamesmead: questions
Do you cover Thamesmead?
Yes. We cover Thamesmead, including the SE28 postcode area, as part of Greater London. Send photos by WhatsApp or the form for a free guide price, and we'll confirm the fixed price in writing before any work starts.
Can you repair a lantern someone else installed in Thamesmead?
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.
Do I need to be home?
If we need to water-test or check the inside of the lantern, yes. Exterior-only work can sometimes be done with access arranged in advance.
Will you show me what was wrong?
Yes. We photograph the failed detail and the finished repair and send them to you with the invoice.
Other lantern repairs in Thamesmead
- Upstand and kerb repairs in Thamesmead
- Condensation diagnosis and fixes in Thamesmead
- uPVC roof lantern repairs in Thamesmead
- Opening vent and actuator repairs in Thamesmead
- Leak investigation and inspection in Thamesmead
- Cleaning and maintenance in Thamesmead
Roof lantern leak repairs near Thamesmead
More about roof lantern leak repairs · All roof lantern repairs in Thamesmead