In Abergavenny, 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.

Is it time for condensation diagnosis and fixes?
- Drips after cooking, showers or drying clothes
- Black mould at the base of the lantern lining
- Wet window sills elsewhere in the house too
Why it happens
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.
About Abergavenny and the NP7 area
Damp, mild winters keep moss and algae growing on flat roofs and lantern frames, which holds water against seals and blocks weep slots. Regular clearing makes a real difference in wetter areas.
From Newport, Gwent to Abergavenny is roughly 16 miles — all part of the Gwent area we cover.
If you're just outside Abergavenny, we also cover Pontypool (8 miles), Ebbw Vale (9 miles), Tredegar (10 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?
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 Abergavenny: questions
How do I get a price for condensation diagnosis and fixes in Abergavenny?
Send a few photos of the lantern and the problem, with your Abergavenny postcode. We'll reply with a guide price and tell you whether a visit is needed before we can fix the price.
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.
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.
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Condensation diagnosis and fixes near Abergavenny
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