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 Dolgellau (LL40) 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
- Sealant applied over sealant from previous patch repairs
- 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.
Patch over patch
Fresh sealant run over old, dirty sealant rarely bonds. It looks fixed for a season and then lets go.
Covering Dolgellau and nearby
Western and upland parts of the UK get more rain and more wind-driven rain than the east, and that's what finds weak cappings and blocked eaves first. Lanterns here benefit from a check of the bars on the most exposed face and a clear eaves channel before winter.
Coastal wind drives rain hard against lanterns, so cappings and ridge seals on the seaward face take the most punishment.
We cover Dolgellau as part of Gwynedd, about 35 miles from Bangor, Gwynedd.
Close by, we also cover Machynlleth (11 miles), Porthmadog (16 miles), Aberystwyth (24 miles).
What should you expect to pay in Dolgellau?
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 Wales?
Straightforward repairs — resealing, gaskets, cappings, eaves and like-for-like parts — don't normally need building regulations approval in Wales. Replacing the whole lantern or enlarging the opening is different and falls under the Building Regulations 2010 (as applied in Wales); we confirm in writing which route applies before any replacement. 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 Dolgellau: questions
Can you repair a lantern someone else installed in Dolgellau?
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 Dolgellau do you cover?
As well as Dolgellau, we cover nearby Machynlleth, Porthmadog, Aberystwyth, Pwllheli and the rest of Gwynedd.
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 Dolgellau
- Roof lantern leak repairs in Dolgellau
- Slipped glass panel repairs in Dolgellau
- Solar control and self-cleaning glass upgrades in Dolgellau
- Aluminium roof lantern repairs in Dolgellau
- uPVC roof lantern repairs in Dolgellau
- Opening vent and actuator repairs in Dolgellau
Roof lantern resealing near Dolgellau
More about roof lantern resealing · All roof lantern repairs in Dolgellau