In Blackwood, as everywhere, each glazing bar on a roof lantern has a top capping that clamps the glass onto gaskets. Send photos and we'll tell you what we think has failed.

What you might be seeing
- A capping visibly higher than its neighbours
- Water running down one glazing bar inside
- End caps missing at the bottom of a bar
What usually causes it?
Gasket shrinkage
Rubber gaskets shrink back from the ends over time, leaving a gap at the ridge or eaves.
Fixings working loose
Screws and clips that hold the capping relax with thermal movement, so the clamp on the glass weakens.
Roof lanterns in Blackwood
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.
We cover Blackwood as part of Gwent, about 11 miles from Newport, Gwent.
If you're just outside Blackwood, we also cover Risca (6 miles), Caerphilly (6 miles), Pontypridd (7 miles).
What should you expect to pay in Blackwood?
Guide price for glazing bar and capping repairs: £165–£395 ex VAT (£198–£474 inc VAT), per lantern. 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.
Glazing bar and capping repairs in Blackwood: questions
Do you need to visit to price glazing bar and capping repairs?
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.
Which places near Blackwood do you cover?
As well as Blackwood, we cover nearby Risca, Caerphilly, Pontypridd, Pontypool and the rest of Gwent.
Can a capping just be clipped back on?
Sometimes, if nothing underneath has failed. We check the gaskets first, because clipping a capping over a perished gasket doesn't stop the leak.
Do you repair uPVC and timber lantern bars too?
Yes. Timber lanterns use different beads and cappings, and we repair those as part of timber lantern repairs.
Other lantern repairs in Blackwood
- Ridge and hip repairs in Blackwood
- Eaves beam and gutter repairs in Blackwood
- Upstand and kerb repairs in Blackwood
- uPVC roof lantern repairs in Blackwood
- Cleaning and maintenance in Blackwood
- Roof lantern replacement in Blackwood
Glazing bar and capping repairs near Blackwood
More about glazing bar and capping repairs · All roof lantern repairs in Blackwood