In Porthmadog, as everywhere, the ridge is where the hip bars and glazing bars meet at the top of a lantern, usually under a moulded or pressed end cap. Send photos and we'll tell you what we think has failed.

What you might be seeing
- Drips near the centre or top of the lantern
- A cracked or faded ridge end cap
- Sealant around the ridge cap split or missing
Why it happens
Movement at the junction
Several bars meet at one point and each moves slightly with temperature; the seals at the ridge take the strain.
Poor original sealing
Ridge details are fiddly. If the original sealing was rushed, it's often the first place to leak.
About Porthmadog and the LL49 area
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.
Near the coast, salt in the air is hard on aluminium finishes and fixings; washing the frame occasionally and touching in chips keeps corrosion away.
We cover Porthmadog as part of Gwynedd, about 21 miles from Bangor, Gwynedd.
We also cover nearby Pwllheli (12 miles), Caernarfon (16 miles), Dolgellau (16 miles).
What should you expect to pay in Porthmadog?
Typical range: £195–£445 ex VAT, which is £234–£534 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 Wales?
Most lantern repairs in Wales need no approval at all. Where a job turns into a replacement, the Building Regulations 2010 (as applied in Wales) apply and we confirm how the work will be signed off before we start. 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.
Ridge and hip repairs in Porthmadog: questions
Do you cover Porthmadog?
Yes. We cover Porthmadog, including the LL49 postcode area, as part of Gwynedd. 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.
Can you repair a lantern someone else installed in Porthmadog?
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.
What does a ridge repair cost?
Usually £195–£445 ex VAT for a standard lantern, confirmed in writing before work starts.
Can you replace just the ridge cap?
Yes, if a compatible cap is available and the seals underneath are sound.
Other lantern repairs in Porthmadog
- Upstand and kerb repairs in Porthmadog
- Condensation diagnosis and fixes in Porthmadog
- Timber roof lantern repairs in Porthmadog
- Flat rooflight and skylight repairs in Porthmadog
- Leak investigation and inspection in Porthmadog
- Cleaning and maintenance in Porthmadog
Ridge and hip repairs near Porthmadog
More about ridge and hip repairs · All roof lantern repairs in Porthmadog