In Nailsea, 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.

Signs you need misted glass unit replacement
- Fog, droplets or white bloom between the panes
- One pane looks hazier than the others
- Water marks or tide lines inside the unit
What usually causes it?
Edge seal failure
Every sealed unit has an edge seal and desiccant. Once the seal fails, humid air gets in and the desiccant saturates.
Water sitting on the edge
If the unit's edge sits in water because the eaves don't drain, the seal fails sooner.
About Nailsea and the BS48 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.
Nailsea is around 32 miles from Taunton, and both are within our Somerset coverage.
We also cover nearby Portishead (3 miles), Clevedon (4 miles), Bristol (7 miles).
How much should it cost?
Guide price for misted glass unit replacement: £245–£595 ex VAT (£294–£714 inc 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?
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.
Misted glass unit replacement in Nailsea: questions
Do you cover Nailsea?
Yes. We cover Nailsea, including the BS48 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.
Do you need to visit to price misted glass unit replacement?
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.
How much does a misted lantern unit cost to replace?
Usually £245–£595 ex VAT per unit depending on size, glass spec and access, confirmed in writing before work starts.
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.
Other lantern repairs in Nailsea
- Roof lantern leak repairs in Nailsea
- Ridge and hip repairs in Nailsea
- Cracked lantern glass replacement in Nailsea
- Timber roof lantern repairs in Nailsea
- uPVC roof lantern repairs in Nailsea
- Commercial roof lantern repairs in Nailsea
Misted glass unit replacement near Nailsea
More about misted glass unit replacement · All roof lantern repairs in Nailsea