Covering County Antrim
Our single-storey extensions service in County Antrim covers Belfast, Lisburn, Newtownabbey and Carrickfergus and more.
Homes in County Antrim
Across Northern Ireland you find city terraces, suburban semis and rural bungalows and farmhouses, so the right approach depends on the plot and the planning history.
What do you get with a single-storey extension?
A single-storey extension adds one level of new floor space to the back or side of a house, usually to open up a kitchen, dining or family room. It is the most common way to gain space without moving, and many can be built without a planning application.
- Measured survey and design drawings
- Foundations, drainage and structural steel
- Brickwork, roof, glazing and insulation
What is the guide price for a single-storey extension in County Antrim?
Guide prices for single-storey extensions, including VAT where it applies. Your fixed price is confirmed in writing after the survey.
| Single-storey extensions | Guide price incl. VAT |
|---|---|
| Standard specification | £2,600 to £3,000 per m² |
| Good specification | £3,000 to £3,500 per m² |
| High specification | £3,500 to £4,000 per m² |
Do you need permission for a single-storey extension in County Antrim?
Northern Ireland projects need planning clearance and building control approval from the local council. We prepare the applications and agree any work near neighbouring property directly with the neighbours.
In Northern Ireland permitted development is set by the Planning (General Permitted Development) Order (Northern Ireland) 2015, and small single-storey rear extensions can often go ahead without an application.
What should I think about before starting?
- Drains under the footprint may need diverting or a build-over agreement with the water company.
- Large glazed areas need to meet energy rules, which can shape the size of doors and rooflights.
From first call to completion
- Send us the details. Give us a postcode, a rough idea of size and some photos, by phone, form or the guide price tool.
- Free site visit. We measure up, look at access, drains and the structure, and talk through options and budget.
- Drawings, approvals, written quote. We prepare the design, apply for the approvals it needs, and give you a fixed price in writing.
- We build it. Work follows an agreed programme, with inspections at each stage and a final sign-off.
Questions about a single-storey extension in County Antrim
How much does a single-storey extension cost?
Most single-storey extensions cost about £2,600 to £4,000 per square metre including VAT, depending on specification, glazing and ground conditions. We give a fixed price in writing for the agreed specification after the survey.
Can we stay in the house during the build?
Usually yes. We keep the existing house closed off from the works until the knock-through near the end, and agree a temporary kitchen set-up with you if the kitchen is affected.
How do I get a price for single-storey extensions in County Antrim?
Use the guide price tool for a ballpark figure, then book a visit for a fixed written price for the agreed specification.
Single-storey extensions in nearby towns
- Single-storey extensions in Belfast
- Single-storey extensions in Lisburn
- Single-storey extensions in Newtownabbey
- Single-storey extensions in Carrickfergus
- Single-storey extensions in Ballymena
- Single-storey extensions in Ballymoney
- Single-storey extensions in Portrush
Learn more about single-storey extensions, or see every project we cover in County Antrim.

