We carry out condensation diagnosis and fixes in Brecon and across the LD3 area. Condensation forms when warm, humid air meets a cold surface — and a roof lantern is the coldest surface in many kitchens.

What you might be seeing
- 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?
High humidity
Cooking, kettles, showers, drying washing and people all add moisture to the air.
Poor ventilation
Without trickle vents, extraction or an opening vent, moist air has nowhere to go.
Roof lanterns in Brecon
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.
From Newtown to Brecon is roughly 40 miles — all part of the Powys area we cover.
Close by, we also cover Tredegar (13 miles), Merthyr Tydfil (14 miles), Ebbw Vale (14 miles).
How much should it cost?
Guide price for condensation diagnosis and fixes: £145–£495 ex VAT (£174–£594 inc 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?
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.
Condensation diagnosis and fixes in Brecon: questions
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.
Which places near Brecon do you cover?
As well as Brecon, we cover nearby Tredegar, Merthyr Tydfil, Ebbw Vale, Aberdare and the rest of Powys.
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.
What does a condensation visit cost?
Diagnosis visits start from £145 ex VAT. Any fixes are priced separately and confirmed in writing before work starts.
Other lantern repairs in Brecon
- Glazing bar and capping repairs in Brecon
- Ridge and hip repairs in Brecon
- Eaves beam and gutter repairs in Brecon
- Cracked lantern glass replacement in Brecon
- Roof lantern respraying in Brecon
- Roof lantern replacement in Brecon
Condensation diagnosis and fixes near Brecon
More about condensation diagnosis and fixes · All roof lantern repairs in Brecon