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Derry/Londonderry · BT48 · County Londonderry

Dome rooflight replacement in Derry/Londonderry

Dome rooflight replacement in Derry/Londonderry comes down to what happens around the glass. A good unit sat on a poor upstand, or with the membrane or flashing cut short at the corners, will still let water in. We fit each dome rooflight to the maker's instructions for fixings, packers and sealant, for homes and businesses across Derry/Londonderry and the rest of County Londonderry. That covers supply and fit, fit-only for a unit you already own, and swapping out a tired one. Every job starts with a written quote, so the price and scope are clear before anyone climbs a ladder.

Guide price from £395 · Supply & fit, per dome; building control notice fee extra on homes in England and Wales

What the job costs in Derry/Londonderry

Like-for-like dome

£395 – £695including VAT at 20%

Old dome taken off, new multi-skin dome fixed to the sound existing kerb

Dome with kerb adaptor

£695 – £1,195including VAT at 20%

New dome where the kerb needs an adaptor or packing

Upgrade to glass

£1,095 – £1,695including VAT at 20%

Dome swapped for a double-glazed glass rooflight on the existing sound kerb, as in our replacement service

Guide ranges for supply & fit, per dome; building control notice fee extra on homes in England and Wales. Your price is fixed in a written quote after we have seen photos or surveyed. Scaffold, access towers or a crane are priced separately if the job needs them, and building control fees, where a job needs them, are shown as their own line.

Areas around Derry/Londonderry we cover

Covering Derry/Londonderry means covering the people who live and work there, not a single postcode. We take on domestic and commercial jobs in BT48, BT47 and BT49, and are happy to quote further out in Coleraine and Omagh. If your address sits between towns, tell us and we will confirm whether it falls in our normal area or needs travel set out separately on the quote.

Buying your own, or letting us supply

Supply and fit tends to suit people who would rather not pick a unit from a catalogue. We look at the roof, the opening and how you use the room, then put a dome rooflight on the quote that fits all three. Fit-only suits people who already know what they want, or have one on site. We are happy with either. The difference is who stands behind what: on fit-only, the maker or retailer covers the product, and our workmanship guarantee covers the installation.

What we do on the day

  • Old dome unscrewed, lifted off and taken away
  • Membrane checked where it meets the kerb, with small repairs made
  • Adaptor or packing fitted where the old kerb needs it
  • Multi-skin domes and energy — We fit multi-skin domes rather than single-skin ones as replacements.
  • Kerb size and adaptors — We measure every kerb against the new dome's sizes.

What happens on the day

Fitting days start with a look at the sky. If rain is due, the order of work changes so the roof is never left open to it. A typical day for a dome rooflight runs like this: set up access, protect the room, open up the roof or prepare the existing kerb or frame, check sizes, fix, seal, then finish inside. On jobs that take more than a day, the opening is weather-sealed overnight. The last hour goes on tidying, waste removal and a walk-round with you.

Planning, building control and Derry/Londonderry

Northern Ireland has its own rules. Permitted development for rooflights on a house requires the unit to sit below the highest part of the roof, project no more than 15 cm where the slope faces a road, and stay at least half a metre from the ridge, eaves, party wall and verge. It doesn't apply in conservation areas or within the grounds of a listed building. For building control, structural roof alterations need an application, and rooflights must meet WER Band C or 1.6 W/m²K.

What to send for a quick quote

Start with your phone. Take a picture of the roof where the unit goes or already sits, then one from inside looking up. Measure what you can, even roughly. Tell us what the roof is covered with and how a fitter would reach it: ladder, garden access or scaffold. Bought it already? Send the link or spec. Add your full postcode, for example in BT48, and we can price it.

Common questions in Derry/Londonderry

Will my new dome rooflight leak?

A correctly fitted unit should not. Leaks usually trace back to the detail around the frame: an upstand that is too low, a membrane or flashing that is not dressed properly, sealant applied to a damp surface, or water ponding against the kerb. We fit to the maker's instructions and check each of those points. The fitting carries a written workmanship guarantee, with its terms set out on your quote.

Do you need scaffolding to fit a rooflight?

Not always. Single-storey roofs can often be reached safely with ladders, a tower or edge protection. Higher roofs, steep pitches and large units usually need scaffold or a mobile platform, and heavy glass may need a crane. We assess access from your photos or at the survey, and any scaffold or lifting cost is shown as its own line on the written quote.

Can you fit the dome rooflight I bought online?

Yes, fit-only is one of our core services. Send the product link or spec, photos of the roof and rough sizes, and we can usually price it from those. Before fitting we check the delivery for damage, which should be reported to the seller, plus the size against the builder's opening and the upstand height. The product warranty stays with the maker or seller, and our guarantee covers the fitting.

Tell us your postcode, BT48 or close by, and what you want fitted. We will reply with the next steps and a quote.

Rear extension at dusk with lit rooflights and a roof lantern
Ready when you are

Dome replacement in Derry/Londonderry

Send photos and rough sizes, or ask for a survey for install work. One fixed written price before anything starts.

CallGet a quote