In Rhondda, 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.

What you might be seeing
- Water on the inside of the glass on cold mornings, even without rain
- Drips after cooking, showers or drying clothes
- 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.
About Rhondda and the CF42 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.
Rhondda is around 12 miles from Bridgend, and both are within our Mid Glamorgan coverage.
Close by, we also cover Tonypandy (3 miles), Aberdare (4 miles), Pontypridd (6 miles).
How much should it cost?
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?
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 Rhondda: questions
Can you repair a lantern someone else installed in Rhondda?
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 Rhondda do you cover?
As well as Rhondda, we cover nearby Tonypandy, Aberdare, Pontypridd, Merthyr Tydfil and the rest of Mid Glamorgan.
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 Rhondda
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- Leak investigation and inspection in Rhondda
Condensation diagnosis and fixes near Rhondda
More about condensation diagnosis and fixes · All roof lantern repairs in Rhondda