What is a kitchen extension?

A kitchen extension is an extension designed around a new kitchen, usually an open-plan kitchen, dining and family space at the back of the house. We build the extension and fit the kitchen as one project, so plumbing, electrics and lighting are planned around the layout from the start.
How much does a kitchen extension cost in County Down?
In County Down, a kitchen extension typically costs £1,950–£2,900 per m² including a mid-range kitchen, including VAT at 20% (standard rate). For a typical 22 m² project that is roughly £43,000–£64,000. 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 (15 m²) | £29,000–£43,500 |
| Typical project (22 m²) | £43,000–£64,000 |
| Larger project (31 m²) | £60,500–£90,000 |
| Rate per m² | £1,950–£2,900 |
Your quote will depend mainly on:
- Extension size and roof design
- Glazing and roof lanterns
- Kitchen units, worktops and appliances
- Island with sink or hob, which needs services in the floor
Your exact price depends on the survey and drawings. The guide price tool gives a quick range in the meantime.
Do you need planning permission for a kitchen extension in County Down?
The approval route for County Down is set by planning law in Northern Ireland. In Northern Ireland the Planning (General Permitted Development) Order (Northern Ireland) 2015 allows single-storey rear extensions of up to 3 metres on attached houses and 4 metres on detached houses, no higher than 4 metres, with eaves no higher than 3 metres within 2 metres of a boundary. Houses with removed rights need planning permission, listed buildings need consent, and in conservation areas extensions must stay single-storey and must not come forward of the front or side walls.
Northern Ireland has no Party Wall Act. Work on shared walls relies on agreement with the neighbour and common law, so we agree the arrangements in writing before work starts.
If the answer is not clear-cut, we can apply for formal confirmation before you commit to the build.
What we handle
The work we manage on a kitchen extension:
- Flooring and decoration
- Kitchen fitting, worktops and splashbacks
- Extension structure, roof and glazing
- Extraction ducted to outside
- Electrics, lighting plan and sockets
- Kitchen layout planned alongside the extension design
How long does it take?
Expect 11 to 16 weeks on site, including kitchen fitting. Before that, surveys, drawings and approvals usually take 6 to 12 weeks, longer if the council asks for changes.
Building in County Down
Across Northern Ireland, bungalows and chalet bungalows are common, so loft conversions and rear extensions are popular projects.
Towns we cover in County Down include Bangor, Newtownards, Newry, Banbridge and Downpatrick.
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
Permissions sorted
Applications, building control and neighbour arrangements, all before the start date.
- 04
Construction and completion
We build, put right any snags and hand over the building control certificate.
Questions about kitchen extensions in County Down
Should the kitchen be designed before the extension?
Yes. Knowing where the sink, hob and island will go lets us place drains, ducting, sockets and windows correctly during the build.
Can I buy my own kitchen?
Yes. You can supply it and we fit it, or we supply it as part of the price. Either way we coordinate deliveries with the build programme.
Do I need planning permission for a kitchen extension in County Down?
In Northern Ireland the Planning (General Permitted Development) Order (Northern Ireland) 2015 allows single-storey rear extensions of up to 3 metres on attached houses and 4 metres on detached houses, no higher than 4 metres, with eaves no higher than 3 metres within 2 metres of a boundary. Houses with removed rights need planning permission, listed buildings need consent, and in conservation areas extensions must stay single-storey and must not come forward of the front or side walls.
How long does a kitchen extension take in County Down?
Typically 11 to 16 weeks on site, including kitchen fitting. Design and approvals beforehand usually take 6 to 12 weeks.
How much does a kitchen extension cost in County Down?
In County Down, a kitchen extension typically costs £1,950–£2,900 per m² including a mid-range kitchen, including VAT at 20% (standard rate). A typical 22 m² project comes to roughly £43,000–£64,000. Your fixed price depends on the survey and drawings.
Is underfloor heating worth it?
In a large open-plan space it frees wall space for units and glazing and gives even heat. It is easiest to fit during the build.
