In Penarth, 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
- Several small leaks rather than one obvious one
- A lantern that is 8–15 years old and has never been maintained
Why it happens
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.
Covering Penarth and nearby
Wind-driven rain is the real test of a roof lantern, and the wetter west sees plenty of it. Leaks that appear only in a storm from one direction usually point to the cappings or eaves on that face — a useful clue when you send us photos.
We cover Penarth as part of South Glamorgan, about 3 miles from Cardiff.
Neighbouring places we cover include Cardiff (3 miles), Barry (5 miles), Caerphilly (10 miles).
How much should it cost?
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 Penarth: questions
Do you cover Penarth?
Yes. We cover Penarth, including the CF64 postcode area, as part of South Glamorgan. 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.
Which places near Penarth do you cover?
As well as Penarth, we cover nearby Cardiff, Barry, Caerphilly, Cowbridge and the rest of South Glamorgan.
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.
How long does resealing take?
Most domestic lanterns take a few hours in dry weather.
Other lantern repairs in Penarth
- Glazing bar and capping repairs in Penarth
- Upstand and kerb repairs in Penarth
- Timber roof lantern repairs in Penarth
- Opening vent and actuator repairs in Penarth
- Leak investigation and inspection in Penarth
- Urgent leak make-safe in Penarth
Roof lantern resealing near Penarth
More about roof lantern resealing · All roof lantern repairs in Penarth