In Bath, 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?
- 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.
About Bath and the BA1 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.
Neighbouring places we cover include Trowbridge (8 miles), Frome (10 miles), Bristol (12 miles).
Guide prices for condensation diagnosis and fixes in Bath
Most condensation diagnosis and fixes jobs come in between £145 and £495 ex VAT (£174–£594 including 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 Bath: questions
Do you cover Bath?
Yes. We cover Bath, including the BA1 postcode area, as part of Somerset. Send photos by WhatsApp or the form for a free guide price, and we'll confirm the fixed price in writing before any work starts.
Which places near Bath do you cover?
As well as Bath, we cover nearby Trowbridge, Frome, Bristol, Yate and the rest of Somerset.
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.
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.
Other lantern repairs in Bath
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Condensation diagnosis and fixes near Bath
More about condensation diagnosis and fixes · All roof lantern repairs in Bath