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 from Gorseinon (SA4) and we'll tell you which it is — with the price agreed in writing before any work.

Is it time for misted glass unit replacement?
- Fog, droplets or white bloom between the panes
- One pane looks hazier than the others
- Misting that comes and goes with the weather
What usually causes it?
Water sitting on the edge
If the unit's edge sits in water because the eaves don't drain, the seal fails sooner.
Movement and age
Thermal movement and age wear the seal; units at the bottom of the lantern often go first.
Covering Gorseinon and nearby
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.
We cover Gorseinon as part of West Glamorgan, about 5 miles from Swansea.
Neighbouring places we cover include Llanelli (5 miles), Swansea (5 miles), Ammanford (9 miles).
What should you expect to pay in Gorseinon?
Typical range: £245–£595 ex VAT, which is £294–£714 with 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?
Straightforward repairs — resealing, gaskets, cappings, eaves and like-for-like parts — don't normally need building regulations approval in Wales. Replacing the whole lantern or enlarging the opening is different and falls under the Building Regulations 2010 (as applied in Wales); we confirm in writing which route applies before any replacement. 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 Gorseinon: questions
How do I get a price for misted glass unit replacement in Gorseinon?
Send a few photos of the lantern and the problem, with your Gorseinon postcode. We'll reply with a guide price and tell you whether a visit is needed before we can fix the price.
Which places near Gorseinon do you cover?
As well as Gorseinon, we cover nearby Llanelli, Swansea, Ammanford, Neath and the rest of West Glamorgan.
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 Gorseinon
- Glazing bar and capping repairs in Gorseinon
- Eaves beam and gutter repairs in Gorseinon
- Solar control and self-cleaning glass upgrades in Gorseinon
- Opening vent and actuator repairs in Gorseinon
- Flat rooflight and skylight repairs in Gorseinon
- Leak investigation and inspection in Gorseinon
Misted glass unit replacement near Gorseinon
More about misted glass unit replacement · All roof lantern repairs in Gorseinon