In South Croydon, as everywhere, 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 and we'll tell you what we think has failed.

What you might be seeing
- Black mould or dirt lines trapped in old silicone
- Sealant applied over sealant from previous patch repairs
- A lantern that is 8–15 years old and has never been maintained
What usually causes it?
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.
Roof lanterns in South Croydon
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.
South Croydon is around 10 miles from Westminster, and both are within our Greater London coverage.
If you're just outside South Croydon, we also cover Croydon (1 mile), Purley (2 miles), Wallington (3 miles).
What should you expect to pay in South Croydon?
Typical range: £245–£495 ex VAT, which is £294–£594 with 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 South Croydon: questions
How do I get a price for roof lantern resealing in South Croydon?
Send a few photos of the lantern and the problem, with your South Croydon postcode. We'll reply with a guide price and tell you whether a visit is needed before we can fix the price.
Which places near South Croydon do you cover?
As well as South Croydon, we cover nearby Croydon, Purley, Wallington, Carshalton 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 South Croydon
- Misted glass unit replacement in South Croydon
- Solar control and self-cleaning glass upgrades in South Croydon
- uPVC roof lantern repairs in South Croydon
- Opening vent and actuator repairs in South Croydon
- Leak investigation and inspection in South Croydon
- Orangery lantern repairs in South Croydon
Roof lantern resealing near South Croydon
More about roof lantern resealing · All roof lantern repairs in South Croydon