Flat rooflights fail in the same places as lanterns: the seal to the upstand, the roof junction and the glass unit. Send photos from Larne (BT40) and we'll tell you which it is — with the price agreed in writing before any work.

What you might be seeing
- Water around the rooflight edge
- Misted glass
- Ponding on the glass (not enough fall)
Why it happens
No fall
Flat glass needs a slight fall to shed water; ponding stresses seals.
Upstand detail
As with lanterns, the membrane must be dressed up and sealed.
About Larne and the BT40 area
Wind-driven rain is the real test of a roof lantern, and the wetter west sees plenty of it. Leaks that appear only in a storm from one direction usually point to the cappings or eaves on that face — a useful clue when you send us photos.
Coastal wind drives rain hard against lanterns, so cappings and ridge seals on the seaward face take the most punishment.
From Belfast to Larne is roughly 18 miles — all part of the County Antrim area we cover.
Neighbouring places we cover include Carrickfergus (9 miles), Newtownabbey (14 miles), Bangor, Down (14 miles).
How much should it cost?
Typical range: £195–£595 ex VAT, which is £234–£714 with VAT, per rooflight. 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?
Straightforward repairs — resealing, gaskets, cappings, eaves and like-for-like parts — don't normally need building regulations approval in Northern Ireland. Replacing the whole lantern or enlarging the opening is different and falls under the Building Regulations (Northern Ireland) 2012; we confirm in writing which route applies before any replacement. 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.
Flat rooflight and skylight repairs in Larne: questions
Do you cover Larne?
Yes. We cover Larne, including the BT40 postcode area, as part of County Antrim. Send photos by WhatsApp or the form for a free guide price, and we'll confirm the fixed price in writing before any work starts.
How do I get a price for flat rooflight and skylight repairs in Larne?
Send a few photos of the lantern and the problem, with your Larne postcode. We'll reply with a guide price and tell you whether a visit is needed before we can fix the price.
What does a flat rooflight repair cost?
Usually £195–£595 ex VAT, confirmed in writing before work starts.
Do you replace walk-on rooflight glass?
Walk-on glass is a specialist structural unit; we can measure and specify a replacement from the right manufacturer.
Other lantern repairs in Larne
- Eaves beam and gutter repairs in Larne
- Misted glass unit replacement in Larne
- Cracked lantern glass replacement in Larne
- Cleaning and maintenance in Larne
- Roof lantern replacement in Larne
- Commercial roof lantern repairs in Larne
Flat rooflight and skylight repairs near Larne
More about flat rooflight and skylight repairs · All roof lantern repairs in Larne