What the job costs in Derry/Londonderry
Onto a ready upstand
Customer-supplied unit up to about 1.5 m², fitted to a prepared kerb, sealed and trimmed
With a new upstand
Insulated timber upstand built, membrane turned up and dressed, unit fitted and sealed
Large or heavy unit
Extra hands or lifting gear, larger openings, fixed or opening units
Guide ranges for labour only — you supply the rooflight. 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.
Covering BT48 and neighbouring districts
Looking at a property near Derry/Londonderry but not quite in it? We work across BT48, BT47 and BT49 and outwards to Coleraine, Omagh and Dungannon. Give us the full postcode when you get in touch, because access, parking and the route for a large unit all depend on the exact street. Those details shape the quote for any job around Derry/Londonderry.
What we check on a supplied unit
A damaged delivery is a frequent snag on fit-only work. Before the day, unpack a rooflight, photograph it, and tell the seller about any cracks or scuffs, because claims are much easier made early. We will also ask for the model or a link, so we can read the maker's instructions and check the builder's opening size and the upstand height it expects. If everything lines up, we fit it. If not, we explain what needs changing first.
What the job includes
- Opening tested where relevant, packaging taken away and paperwork handed back
- Upstand height, level and fall checked, and squareness confirmed across the diagonals
- Check of the delivered unit, glass, fixings pack and instructions before work starts
- Upstand height above the roof — We measure how far the upstand stands above the finished roof surface, including any ballast or walkway.
- Warranty conditions on your unit — We read the warranty terms that came with your rooflight before we fit it.
From arrival to clean-up
Where a job takes half a day to a day, the split is usually structural work first and finishing second. Early on, the fitters cut or prepare the opening, trim where needed and prepare the upstand or flashing. Then a rooflight is lifted in, fixed and made weathertight so the roof is sound before anyone moves inside. Plasterboard, trim and filler for the reveal come after. Each evening the work area is swept, and at the end the glass is cleaned and the team talks you through what was done.
Do you need permission in 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.
Getting a price from photos
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
How long does fitting take?
Fitting a rooflight into an existing, correctly sized opening is often a day's work. New openings take longer, because joists or rafters need trimming, an upstand or flashing has to be built or fitted, and the inside needs finishing. Large units that need lifting gear, and days lost to rain, can stretch things further. Your written quote gives a realistic estimate for your roof.
Will my new 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.
Can you replace an old dome without redoing the whole roof?
Usually, yes. If the existing kerb is sound, level and tall enough, a new unit can often sit on it with a fresh seal to the roof covering. If the kerb is rotten or too low, we rebuild it and patch the covering around it rather than stripping the whole roof. This is checked at the survey and included in the written quote, so you know the full scope first.
Questions before you commit? Send them over with your Derry/Londonderry postcode and we will answer them plainly, with a quote alongside.

