Condensation forms when warm, humid air meets a cold surface — and a roof lantern is the coldest surface in many kitchens. We carry out condensation diagnosis and fixes across Dyfed, with a guide price from your photos and a fixed price in writing before any work starts.

Signs you need condensation diagnosis and fixes
- Water on the inside of the glass on cold mornings, even without rain
- Black mould at the base of the lantern lining
- Wet window sills elsewhere in the house too
What usually causes it?
Cold surfaces
Older glass, uninsulated kerbs and un-thermally-broken frames stay cold and collect condensation.
Poor ventilation
Without trickle vents, extraction or an opening vent, moist air has nowhere to go.
Roof lanterns in Dyfed
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.
What should you expect to pay for condensation diagnosis and fixes in Dyfed?
Typical range: £145–£495 ex VAT, which is £174–£594 with 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 Dyfed: questions
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.
Which towns in Dyfed do you cover?
All of Dyfed, including Carmarthen, Llanelli, Ammanford, Aberystwyth, Cardigan, Haverfordwest. Rural and remote addresses are covered by arrangement.
How do I get a price for condensation diagnosis and fixes in Dyfed?
Send a few photos of the lantern and the problem with your postcode, by WhatsApp or the form. We reply with a guide price and confirm the fixed price in writing before any work starts.
Other repairs in Dyfed
- Roof lantern resealing in Dyfed
- Glazing bar and capping repairs in Dyfed
- Eaves beam and gutter repairs in Dyfed
- Flat rooflight and skylight repairs in Dyfed
- Cleaning and maintenance in Dyfed
- Urgent leak make-safe in Dyfed
Nearby areas
- Condensation diagnosis and fixes in West Glamorgan
- Condensation diagnosis and fixes in Mid Glamorgan
- Condensation diagnosis and fixes in Powys
- Condensation diagnosis and fixes in South Glamorgan
- Condensation diagnosis and fixes in Gwent
More about condensation diagnosis and fixes · All roof lantern repairs in Dyfed