Lisburn at a glance
- Postcode districts
- BT17, BT26, BT27, BT28
- Population
- about 77,506 (GeoNames)
- Council area
- Lisburn and Castlereagh City Council
- Building approval
- Lisburn and Castlereagh City Council building control
- Nearest main town
- Belfast, about 7 miles
- Guide price region
- Northern Ireland (−12% on West Midlands rates)
What makes a good extension roof in Lisburn?
If you're fitting a new kitchen under an extension in Lisburn, that's a good time to replace the roof. It makes sense to rebuild the roof before fitting new units, ceilings and lighting below, and the insulation upgrade makes the room more comfortable all year.
Around Lisburn, flat roofs are common on low-rise post-war blocks of flats and on terraced streets with flat-roofed rear kitchens and bathrooms. Northern Ireland averages roughly 1,150 mm of rain a year, spread over many wet days, so a roof that sheds water quickly to clear outlets lasts far longer than one that holds puddles.
How much does a new extension roof cost in Lisburn?
For Lisburn we use Northern Ireland rates: £2,450–£4,300 is the guide for a 20 m² extension roof in EPDM with a new deck and insulation, VAT included. The fixed price comes after a free survey for new and replacement roofs.
| Job | Guide price inc VAT |
|---|---|
| Extension (20 m²), EPDM, new deck + insulation | £2,450–£4,300 |
| Extension (20 m²), GRP, new deck + insulation | £2,650–£4,750 |
| Extension (20 m²), EPDM, insulation + 1 rooflight upstand | £2,650–£4,600 |
| Single garage (18 m²), EPDM rubber | £1,400–£2,450 |
How long will my kitchen be disrupted by a new roof?
Most single-storey extension roofs are replaced in two to four working days, depending on size, rooflights and weather. The kitchen usually stays in use throughout.
Expect noise during the strip-out, and occasional dust through gaps around old rooflights, so it helps to cover worktops and move anything fragile off high shelves. We strip only what we can make weathertight by the end of each day. If a rooflight or lantern is being lifted and refitted, there may be a temporary cover over the opening for a short time. Resin systems smell while they cure, so keep the windows below the roof closed on that day.
What's included?
- Free survey of the roof, abutment and room below
- New abutment upstand and flashing, plus rebuilt rooflight kerbs
- New deck, vapour control layer and warm-roof insulation
- Building control handled where needed, and a written workmanship guarantee
Building control in Northern Ireland
In Northern Ireland, Technical Booklet F1 sets roof insulation at 0.18 W/m²K when a roof over a heated room is renovated or newly built, where that's feasible. The district council's building control should be contacted before work starts, and we prepare the details it asks for. More on the rules.
Which nearby areas do we also cover?
Extension and kitchen roofs in Lisburn: questions
Do you cover Lisburn?
Yes. Lisburn is part of our County Antrim coverage, including postcode districts BT17, BT26, BT27, BT28. Surveys and roofs are carried out by vetted roofing teams working under S&K Property Investments and Improvement Ltd.
Who checks building regulations for a flat roof in Lisburn?
Where the work needs approval it goes to Lisburn and Castlereagh City Council building control. We tell you at the survey whether your job needs it and deal with the paperwork as part of the quote.
How much does a new extension roof cost in Lisburn?
£2,450–£4,300 for a 20 m² extension roof in EPDM with a new deck and insulation, at Northern Ireland guide rates including VAT. The fixed price comes after a free survey for new and replacement roofs.
Can a sedum roof go on my extension?
Possibly, if the structure can carry the extra weight and the roof has suitable falls and drainage. We check the joists at survey before recommending it.
How do I know my extension roof needs replacing rather than repairing?
Repeated leaks, a soft deck, wet insulation or widespread cracking point to replacement. A single defect on a dry, sound roof can usually be repaired.