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. Send photos from Southall (UB1) and we'll tell you which it is — with the price agreed in writing before any work.

Is it time for roof lantern resealing?
- Cracked, split or shrunken sealant along the bars
- Black mould or dirt lines trapped in old silicone
- A lantern that is 8–15 years old and has never been maintained
Why it happens
Wrong product used
General-purpose or acetoxy silicone can fail early on some frames and coatings. Glazing joints need a low-modulus, compatible sealant.
Patch over patch
Fresh sealant run over old, dirty sealant rarely bonds. It looks fixed for a season and then lets go.
Covering Southall and nearby
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.
Southall is around 10 miles from Westminster, and both are within our Greater London coverage.
Close by, we also cover Greenford (2 miles), Heston (2 miles), Hayes (2 miles).
Guide prices for roof lantern resealing in Southall
Guide price for roof lantern resealing: £245–£495 ex VAT (£294–£594 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.
Roof lantern resealing in Southall: questions
Can you repair a lantern someone else installed in Southall?
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.
Which places near Southall do you cover?
As well as Southall, we cover nearby Greenford, Heston, Hayes, Isleworth and the rest of Greater London.
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.
How long does resealing take?
Most domestic lanterns take a few hours in dry weather.
Other lantern repairs in Southall
- Glazing bar and capping repairs in Southall
- Eaves beam and gutter repairs in Southall
- Cracked lantern glass replacement in Southall
- Solar control and self-cleaning glass upgrades in Southall
- uPVC roof lantern repairs in Southall
- Roof lantern respraying in Southall
Roof lantern resealing near Southall
More about roof lantern resealing · All roof lantern repairs in Southall