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. We carry out misted glass unit replacement across Gwent, with a guide price from your photos and a fixed price in writing before any work starts.

Signs you need misted glass unit replacement
- Fog, droplets or white bloom between the panes
- Misting that comes and goes with the weather
- 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.
Movement and age
Thermal movement and age wear the seal; units at the bottom of the lantern often go first.
Roof lanterns in Gwent
Western and upland parts of the UK get more rain and more wind-driven rain than the east, and that's what finds weak cappings and blocked eaves first. Lanterns here benefit from a check of the bars on the most exposed face and a clear eaves channel before winter.
What should you expect to pay for misted glass unit replacement in Gwent?
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 Wales?
Most lantern repairs in Wales need no approval at all. Where a job turns into a replacement, the Building Regulations 2010 (as applied in Wales) apply and we confirm how the work will be signed off before we start. 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.
Misted glass unit replacement in Gwent: questions
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.
Which towns in Gwent do you cover?
All of Gwent, including Newport, Gwent, Cwmbran, Pontypool, Ebbw Vale, Caerphilly, Risca. Rural and remote addresses are covered by arrangement.
How do I get a price for misted glass unit replacement in Gwent?
Send a few photos of the lantern and the problem with your postcode, by WhatsApp or the form. We reply with a guide price and confirm the fixed price in writing before any work starts.
Other repairs in Gwent
- Condensation diagnosis and fixes in Gwent
- Timber roof lantern repairs in Gwent
- Opening vent and actuator repairs in Gwent
- Roof lantern respraying in Gwent
- Flat rooflight and skylight repairs in Gwent
- Leak investigation and inspection in Gwent
Nearby areas
- Misted glass unit replacement in Mid Glamorgan
- Misted glass unit replacement in South Glamorgan
- Misted glass unit replacement in West Glamorgan
- Misted glass unit replacement in Powys
- Misted glass unit replacement in Dyfed
More about misted glass unit replacement · All roof lantern repairs in Gwent