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 Abergavenny (NP7) and we'll tell you which it is — with the price agreed in writing before any work.

Is it time for roof lantern resealing?
- Black mould or dirt lines trapped in old silicone
- Several small leaks rather than one obvious one
- A lantern that is 8–15 years old and has never been maintained
Common causes we find
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.
Wrong product used
General-purpose or acetoxy silicone can fail early on some frames and coatings. Glazing joints need a low-modulus, compatible sealant.
Roof lanterns in Abergavenny
Damp, mild winters keep moss and algae growing on flat roofs and lantern frames, which holds water against seals and blocks weep slots. Regular clearing makes a real difference in wetter areas.
From Newport, Gwent to Abergavenny is roughly 16 miles — all part of the Gwent area we cover.
We also cover nearby Pontypool (8 miles), Ebbw Vale (9 miles), Tredegar (10 miles).
Guide prices for roof lantern resealing in Abergavenny
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 Wales?
In Wales, like-for-like repairs to a roof lantern don't usually involve building control. A full replacement or a bigger opening is controlled under the Building Regulations 2010 (as applied in Wales), so we set out the route in writing first. Listed buildings in Wales need listed building consent from the local planning authority for alterations, with Cadw guidance on historic buildings; check with the council before changing a lantern on a listed property.
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 Abergavenny: questions
How do I get a price for roof lantern resealing in Abergavenny?
Send a few photos of the lantern and the problem, with your Abergavenny postcode. We'll reply with a guide price and tell you whether a visit is needed before we can fix the price.
Do you need to visit to price roof lantern resealing?
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.
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 Abergavenny
- Ridge and hip repairs in Abergavenny
- Misted glass unit replacement in Abergavenny
- Solar control and self-cleaning glass upgrades in Abergavenny
- Condensation diagnosis and fixes in Abergavenny
- Cleaning and maintenance in Abergavenny
- Urgent leak make-safe in Abergavenny
Roof lantern resealing near Abergavenny
More about roof lantern resealing · All roof lantern repairs in Abergavenny