Guide prices in County Londonderry
Diagnostic visit
Roof and inside inspected, cause found, written repair price
Reseal and re-flash
Failed sealant and flashing taken out, joints cleaned, resealed and taped
Upstand or membrane repair
Rotten kerb section or roof membrane at the upstand repaired
Guide ranges. The first visit is charged and priced before booking; any repair is priced in writing before work starts. 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.
Towns we list in County Londonderry
From the larger towns to the smaller places in between, we take on rooflight fitting across County Londonderry. The process is the same for a terrace, a farmhouse extension or an industrial unit: details first, written quote second, fitting day third. Remote and island addresses in Northern Ireland, where they arise, are covered by arrangement, and we tell you that before quoting.
Included in the work
- Controlled water test where it helps pin down the entry point
- Rotten kerb sections replaced where the timber has gone soft
- Outside inspection of glass, frame, sealant, flashing and roof covering
- Warranty and who fitted it — We ask who fitted the rooflight and when before working on it.
- Water lying against the kerb — We check whether rainwater sits against the upstand after it stops raining.
Rules that apply in Northern Ireland
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.
Common questions in County Londonderry
Should I repair or replace my old leaking rooflight?
It depends on the age and condition of the unit and what has failed. A single perished seal or a blocked channel is worth repairing. A brittle, discoloured dome, a rotten kerb, or several faults at once usually make replacement the better value. After the diagnostic visit we set out both options with prices, so you can decide with the full picture in front of you.
Why is my rooflight leaking?
The usual causes are sealant that has cracked or pulled away, flashing or membrane that has perished at the edges, condensation channels blocked with dirt, water ponding against the kerb, or a seal failing on the glass unit. Sometimes the water is coming in elsewhere and running along to the rooflight. A diagnostic visit finds the real source before anyone starts applying sealant.
Will resealing fix my leaking rooflight?
Sometimes. If the sealant has simply aged and the flashing, upstand and glass are sound, a careful reseal on a dry day can solve it. If the real problem is ponding water, a low upstand or a perished membrane, fresh sealant will only hide it for a while. We tell you which one you are dealing with before recommending any work, and quote the proper fix in writing.

