In Bow, as everywhere, if a roof lantern pane looks cloudy or wet between the two layers of glass, the sealed unit has failed and moisture has got inside. Send photos and we'll tell you what we think has failed.

What you might be seeing
- Fog, droplets or white bloom between the panes
- One pane looks hazier than the others
- Misting that comes and goes with the weather
Common causes we find
Edge seal failure
Every sealed unit has an edge seal and desiccant. Once the seal fails, humid air gets in and the desiccant saturates.
Movement and age
Thermal movement and age wear the seal; units at the bottom of the lantern often go first.
Covering Bow and nearby
Drier, sunnier parts of the UK are kinder to seals than the wet west, but strong sun ages sealant, gaskets and plastic end caps, and south- or west-facing lanterns can make rooms very warm. Solar control glass and an opening vent help.
Across London, many lanterns sit on rear extensions with access only through the house, so we protect floors and plan the work to keep time indoors to a minimum. Parking and any permits are factored into the quote.
Bow is around 5 miles from Westminster, and both are within our Greater London coverage.
We also cover nearby Stratford (1 mile), Canary Wharf (1 mile), Canning Town (2 miles).
What should you expect to pay in Bow?
Most misted glass unit replacement jobs come in between £245 and £595 ex VAT (£294–£714 including VAT), per glass unit. 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?
Straightforward repairs — resealing, gaskets, cappings, eaves and like-for-like parts — don't normally need building regulations approval in England. Replacing the whole lantern or enlarging the opening is different and falls under the Building Regulations 2010; we confirm in writing which route applies before any replacement. 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.
Misted glass unit replacement in Bow: questions
Do you cover Bow?
Yes. We cover Bow, including the E3 postcode area, as part of Greater London. 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.
Can you repair a lantern someone else installed in Bow?
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.
How long does a replacement unit take?
Units are made to measure, so there's a lead time between measuring and fitting. Fitting itself is usually a short visit.
Will the new pane match the others?
We match tint and coatings as closely as possible; a new unit can look very slightly clearer than older neighbours.
Other lantern repairs in Bow
- Ridge and hip repairs in Bow
- Eaves beam and gutter repairs in Bow
- Timber roof lantern repairs in Bow
- Roof lantern respraying in Bow
- Cleaning and maintenance in Bow
- Commercial roof lantern repairs in Bow
Misted glass unit replacement near Bow
More about misted glass unit replacement · All roof lantern repairs in Bow