Roof lantern resealing in Greater London

Resealing is the planned, whole-lantern version of a leak repair: we cut out the old, failed sealant, clean every joint back to a sound surface and reseal the cappings, ridge and eaves with materials that suit the frame. We carry out roof lantern resealing across Greater London, with a guide price from your photos and a fixed price in writing before any work starts.

Sealant being applied along an anthracite aluminium roof lantern glazing bar

Signs you need roof lantern resealing

Cracked, split or shrunken sealant along the bars
Black mould or dirt lines trapped in old silicone
Sealant applied over sealant from previous patch repairs

What usually causes it?

Sealant past its life

Exposed sealant on a roof takes UV, frost and constant expansion and contraction. It hardens, loses grip and pulls away from the glass.

Patch over patch

Fresh sealant run over old, dirty sealant rarely bonds. It looks fixed for a season and then lets go.

Roof lanterns in Greater London

Sun and UV do more damage than rain on many lanterns here: brittle ridge caps, chalky finishes and hardened gaskets. They're cheap to replace before they let water in.

London's extensions are often tight to neighbouring walls and roofs. Where a repair needs access over a neighbour's property, we'll tell you in advance so you can arrange it.

What should you expect to pay for roof lantern resealing in Greater London?

Guide price, per lantern£245–£495 ex VAT£294–£594 inc VAT

Most roof lantern resealing jobs come in between £245 and £495 ex VAT (£294–£594 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?

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 resealing in Greater London: questions

How much does it cost to reseal a roof lantern?

A standard-size lantern on a single-storey extension is usually £245–£495 ex VAT. Larger lanterns, difficult access or gasket replacement add to that, and you get the fixed price in writing first.

Can you match the colour of my frame?

We use sealants in common frame colours such as anthracite grey, black and white, and match as closely as the range allows.

Which towns in Greater London do you cover?

All of Greater London, including Westminster, Islington, Bexley, Barking, Archway, Sutton. Rural and remote addresses are covered by arrangement.

How do I get a price for roof lantern resealing in Greater London?

Send a few photos of the lantern and the problem with your postcode, by WhatsApp or the form. We reply with a guide price and confirm the fixed price in writing before any work starts.

Other repairs in Greater London

Nearby areas

More about roof lantern resealing · All roof lantern repairs in Greater London