What is skylight replacement?
Across County Londonderry, our skylight replacement work covers replacing tired domes and failed glass with a modern rooflight. Survey first, fixed price second, fitting third.
Wind and rain off the Atlantic make upstand and flashing details important on Northern Irish roofs. Many Northern Irish homes have later flat-roofed kitchen extensions where an old dome can be swapped for glass.
Towns in County Londonderry
What you can choose
- Dome to flat glass upgrade
- Upstand rebuild and insulation
- Misted glass unit replacement only
- Roof window replacement in pitched roofs
- Like-for-like size replacement
- Better thermal performance
- Cures most chronic leaks
Planning and building rules in Northern Ireland
Most rooflights on houses in Northern Ireland are permitted development under Class B, but not in a conservation area or on a listed building's curtilage. A side-facing window within 15 m of a neighbouring boundary must be obscure-glazed, and non-opening unless the opening part is more than 1.7 m above the floor.
Technical Booklet F1 (2022) asks for replacement windows and rooflights in existing homes to reach WER Band C or a U-value of 1.6 W/m²K, assessed in the vertical position. Extensions follow a 25% glazing allowance in Technical Booklet F1.
Guide prices
Guide prices for skylight replacement in County Londonderry are the same as anywhere we work — what changes the price is the job: access, structure, scaffold and finishing.
| Option | Guide price inc VAT | Ex VAT |
|---|---|---|
| Replacement with upstand rebuild and opening unit | £2,995 – £4,795 | £2,495 – £3,995 |
| Dome to flat glass upgrade Typical | £1,915 – £2,995 | £1,595 – £2,495 |
| Like-for-like glass rooflight | £1,555 – £2,155 | £1,295 – £1,795 |
How the job runs
- Tell us about the roof. Send the postcode, rough sizes and a photo or two through the form, WhatsApp or the guide-price tool.
- Free survey. For new installations a surveyor measures the opening, checks the roof build-up and talks through glass and options.
- Fixed written quote. You get the product, the work and the price in writing. Nothing is ordered or paid for until you agree.
- Fitting and handover. We fit, seal and make good, then hand over product data, warranties and any certificate paperwork.
Replacement in nearby areas
Common questions
Will it mess up my ceiling?
We protect the room and make good the reveal. Minor decoration may be needed afterwards.
How long does a replacement take?
Usually a day for a standard rooflight on a sound upstand.
Do I need building regulations approval to replace a rooflight?
Replacements in existing homes generally need to meet current thermal standards and may need notification or approval. We advise on the route for your job.
Can you replace only the misted glass?
Sometimes, if the frame is sound and the maker supplies replacement units. Often a complete new rooflight costs little more and performs better.
Will I need planning permission in County Londonderry?
In Northern Ireland, roof alterations come under Class B of the 2015 order: a rooflight facing a road must not project more than 15 cm and must sit at least 0.5 m from the ridge, eaves, verge and party wall.
