Condensation forms when warm, humid air meets a cold surface — and a roof lantern is the coldest surface in many kitchens. Send photos from Dover (CT16) and we'll tell you which it is — with the price agreed in writing before any work.

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
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.
Covering Dover and nearby
Even in drier areas, one heavy downpour with blocked eaves is enough to overflow a lantern indoors. Clearing the eaves channel is the simplest prevention there is.
Near the coast, salt in the air is hard on aluminium finishes and fixings; washing the frame occasionally and touching in chips keeps corrosion away.
From Maidstone to Dover is roughly 36 miles — all part of the Kent area we cover.
Close by, we also cover Folkestone (7 miles), Deal (8 miles), Canterbury (15 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 England?
Most lantern repairs in England need no approval at all. Where a job turns into a replacement, the Building Regulations 2010 apply and we confirm how the work will be signed off before we start. Listed buildings need listed building consent from the local council for alterations, and conservation areas can have extra controls; like-for-like repairs are treated differently from changes, so check with the council's conservation officer first.
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 Dover: 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.
Can you repair a lantern someone else installed in Dover?
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.
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 Dover
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Condensation diagnosis and fixes near Dover
More about condensation diagnosis and fixes · All roof lantern repairs in Dover