In Pwllheli, as everywhere, condensation forms when warm, humid air meets a cold surface — and a roof lantern is the coldest surface in many kitchens. Send photos and we'll tell you what we think has failed.

Signs you need condensation diagnosis and fixes
- Water on the inside of the glass on cold mornings, even without rain
- Drips after cooking, showers or drying clothes
- Black mould at the base of the lantern lining
What usually causes it?
High humidity
Cooking, kettles, showers, drying washing and people all add moisture to the air.
Cold surfaces
Older glass, uninsulated kerbs and un-thermally-broken frames stay cold and collect condensation.
About Pwllheli and the LL53 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.
Coastal wind drives rain hard against lanterns, so cappings and ridge seals on the seaward face take the most punishment.
From Bangor, Gwynedd to Pwllheli is roughly 26 miles — all part of the Gwynedd area we cover.
Close by, we also cover Porthmadog (12 miles), Caernarfon (18 miles), Dolgellau (24 miles).
How much should it cost?
Most condensation diagnosis and fixes jobs come in between £145 and £495 ex VAT (£174–£594 including VAT), per visit. 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.
Condensation diagnosis and fixes in Pwllheli: questions
Do you cover Pwllheli?
Yes. We cover Pwllheli, including the LL53 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.
Do you need to visit to price condensation diagnosis and fixes?
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.
Will new glass stop condensation?
Better glass raises the inner surface temperature and helps, but if the room is very humid, ventilation matters more. We'll tell you which will make the bigger difference.
Is condensation in a lantern normal?
Occasional light condensation on very cold mornings can be. Regular dripping isn't, and can damage linings and cause mould.
Other lantern repairs in Pwllheli
- Glazing bar and capping repairs in Pwllheli
- Solar control and self-cleaning glass upgrades in Pwllheli
- Opening vent and actuator repairs in Pwllheli
- Urgent leak make-safe in Pwllheli
- Orangery lantern repairs in Pwllheli
- Commercial roof lantern repairs in Pwllheli
Condensation diagnosis and fixes near Pwllheli
More about condensation diagnosis and fixes · All roof lantern repairs in Pwllheli