Each glazing bar on a roof lantern has a top capping that clamps the glass onto gaskets. Send photos from Magherafelt (BT45) and we'll tell you which it is — with the price agreed in writing before any work.

Is it time for glazing bar and capping repairs?
- A capping visibly higher than its neighbours
- Gasket rubber poking out, cracked or missing
- 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 Magherafelt
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.
From Derry~Londonderry to Magherafelt is roughly 33 miles — all part of the County Londonderry area we cover.
Neighbouring places we cover include Cookstown (9 miles), Ballymena (15 miles), Antrim (17 miles).
How much should it cost?
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 Northern Ireland?
In Northern Ireland, like-for-like repairs to a roof lantern don't usually involve building control. A full replacement or a bigger opening is controlled under the Building Regulations (Northern Ireland) 2012, so we set out the route in writing first. Listed buildings in Northern Ireland need listed building consent from the council for alterations; check with the council's planning service 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 Magherafelt: 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.
Can you repair a lantern someone else installed in Magherafelt?
Yes. We repair lanterns whoever fitted them. If yours is still under the installer's warranty, contact them first so you don't affect it.
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.
Other lantern repairs in Magherafelt
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- Misted glass unit replacement in Magherafelt
- Condensation diagnosis and fixes in Magherafelt
- Leak investigation and inspection in Magherafelt
- Roof lantern replacement in Magherafelt
- Orangery lantern repairs in Magherafelt
Glazing bar and capping repairs near Magherafelt
More about glazing bar and capping repairs · All roof lantern repairs in Magherafelt