Each glazing bar on a roof lantern has a top capping that clamps the glass onto gaskets. We carry out glazing bar and capping repairs across South Glamorgan, with a guide price from your photos and a fixed price in writing before any work starts.

Signs you need glazing bar and capping repairs
- Gasket rubber poking out, cracked or missing
- Water running down one glazing bar inside
- Rattling or whistling in wind
What usually causes it?
Fixings working loose
Screws and clips that hold the capping relax with thermal movement, so the clamp on the glass weakens.
Damage
Ladders, window cleaning or someone stepping on a lantern can bend a capping or unclip it.
Roof lanterns in South Glamorgan
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 glazing bar and capping repairs in South Glamorgan?
Most glazing bar and capping repairs jobs come in between £165 and £395 ex VAT (£198–£474 including 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 South Glamorgan: questions
How much do capping and gasket repairs cost?
Usually £165–£395 ex VAT per lantern depending on how many bars are affected, confirmed in writing before work starts.
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.
Which towns in South Glamorgan do you cover?
All of South Glamorgan, including Cardiff, Barry, Penarth, Cowbridge, Llantwit Major. Rural and remote addresses are covered by arrangement.
How do I get a price for glazing bar and capping repairs in South Glamorgan?
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 South Glamorgan
- Ridge and hip repairs in South Glamorgan
- Eaves beam and gutter repairs in South Glamorgan
- Upstand and kerb repairs in South Glamorgan
- Opening vent and actuator repairs in South Glamorgan
- Roof lantern replacement in South Glamorgan
- Orangery lantern repairs in South Glamorgan
Nearby areas
- Glazing bar and capping repairs in Mid Glamorgan
- Glazing bar and capping repairs in Gwent
- Glazing bar and capping repairs in West Glamorgan
- Glazing bar and capping repairs in Powys
- Glazing bar and capping repairs in Dyfed
More about glazing bar and capping repairs · All roof lantern repairs in South Glamorgan