What is a wraparound extension?

A wraparound extension combines a side return and a rear extension into one L-shaped addition. It gives the largest possible ground floor, often creating an open-plan kitchen, dining and living space across the whole width of the house.
How much does a wraparound extension cost in County Antrim?
In County Antrim, a wraparound extension typically costs £1,900–£2,750 per m² of floor area, including VAT at 20% (standard rate). For a typical 28 m² project that is roughly £53,000–£77,000. That range is adjusted for Northern Ireland, where domestic building work typically costs around 14% below the national average. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| Smaller project (20 m²) | £38,000–£55,000 |
| Typical project (28 m²) | £53,000–£77,000 |
| Larger project (39 m²) | £74,000–£107,000 |
| Rate per m² | £1,900–£2,750 |
The main things that change the cost:
- Steelwork and propping of the existing house
- Kitchen and flooring specification
- Drainage changes
- Access for materials on terraced streets
For a figure based on your own measurements, try the guide price tool, then book a free home visit for a fixed quote.
Do you need planning permission for a wraparound extension in County Antrim?
Before anything is built in County Antrim, we confirm which approvals apply in Northern Ireland. In Northern Ireland a wraparound extension normally needs planning permission and building control approval.
In Northern Ireland building control approval comes from the council, usually through a full plans application or a building notice, with inspections during the work and a completion certificate at the end.
Our first visit includes a check of your planning history, so you know the route before paying for drawings.
What we handle
The work we manage on a wraparound extension:
- Building control completion
- Walls, roof and glazing
- Design and planning application
- Removal of internal and external walls
- Underfloor heating option, electrics and plastering
- Written agreement with neighbours on shared walls
How long does it take?
Expect 12 to 18 weeks on site. Design and approvals come first and typically take 3 to 4 months, depending on the approval route.
Building in County Antrim
Northern Ireland has many detached and semi-detached homes on generous plots, which suits single-storey rear extensions and garage conversions.
Towns we cover in County Antrim include Belfast, Lisburn, Newtownabbey, Carrickfergus, Ballymena and Antrim.
How it works
- 01
Visit and measured survey
A free visit to understand the project, check access and take measurements.
- 02
Design and pricing
Design options, then a fixed quote based on the chosen drawings and specification.
- 03
Approvals
Planning or permitted development confirmation, building regulations and any party wall matters.
- 04
Build and handover
Work follows the agreed programme, with inspections along the way and a completion certificate at the end.
Questions about wraparound extensions in County Antrim
How long does a wraparound extension take in County Antrim?
Typically 12 to 18 weeks on site. Design and approvals beforehand usually take 3 to 4 months.
Is a wraparound worth it?
It gives the biggest ground-floor space without going upwards. Whether it adds value depends on your street and house, so we suggest checking local sale prices before committing.
Do I need planning permission for a wraparound extension in County Antrim?
In Northern Ireland a wraparound extension normally needs planning permission and building control approval.
Can we keep a separate living room?
Yes. Many clients keep the front room separate and open up only the back of the house.
How much does a wraparound extension cost in County Antrim?
In County Antrim, a wraparound extension typically costs £1,900–£2,750 per m² of floor area, including VAT at 20% (standard rate). A typical 28 m² project comes to roughly £53,000–£77,000. Your fixed price depends on the survey and drawings.
What about the old back addition?
The side wall of the back addition is usually removed and replaced with a steel beam, so the old kitchen joins the new space.
