Antrim, County Antrim
Single-storey rear extension in Antrim
Ground-floor space across the back of the house, usually for a kitchen, dining or family room. If you live in Antrim and want to know what a single-storey rear extension would cost and whether it needs planning, start with the online guide price or a free site visit.
Antrim sits in County Antrim, with postcode districts including BT41. A single-storey rear extension in Antrim is mostly built from the garden side, so the house stays usable for most of the job.
Book a free site visit
Tell us about the house and we'll call to arrange a free, no-obligation visit.
How much does a single-storey rear extension cost in Antrim?
In Antrim, our guide for a single-storey rear extension is £1,650–£2,700 per square metre including VAT for a standard specification. Northern Ireland prices are the lowest in our range.
| Size | Guide price inc VAT |
|---|---|
| 3 m wide × 4 m deep (12 m²) | £20,000–£32,500 |
| 4 m wide × 5 m deep (20 m²) | £33,000–£54,000 |
| 4 m wide × 6 m deep (24 m²) | £39,500–£64,500 |
These are guide ranges; the written quote after the survey is the figure that counts.
Do you need planning permission for a single-storey rear extension in Antrim?
The planning route for a single-storey rear extension in Antrim is set by Northern Ireland's householder rules and your council.
In Northern Ireland the Planning (General Permitted Development) Order (Northern Ireland) 2015 allows a single-storey rear extension of up to 3 metres on an attached house or 4 metres on a detached house, no higher than 4 metres, with eaves no higher than 3 metres within 2 metres of a boundary. Building control approval from the council is still required.
Northern Ireland has no larger-extension prior approval route; anything beyond permitted development needs a planning application.
Conservation areas, Areas of Outstanding Natural Beauty and listed buildings restrict permitted development in Northern Ireland. We check your house's planning history and any conservation area before drawing, so the route is clear before you spend on plans.
What are homes in Antrim like to extend?
Antrim has terraces near the centre, semis on the edges and many detached houses and bungalows in the surrounding countryside, where plots are often generous.
How a single-storey rear extension in Antrim comes together
Survey visit
We visit free of charge, measure up, check access, drainage and neighbours' extensions, and note what you want the room to do.
Drawings and budget
Floor plans and elevations for the options, each with a guide price.
Approvals
Permitted development check or planning application, then building control drawings to the Northern Ireland Technical Booklets and structural calculations, plus a written agreement with neighbours for any shared-wall work.
Build and sign-off
We build to the approved drawings with regular updates, then hand over the building control completion certificate and any guarantees from suppliers.
Single-storey rear extensions near Antrim
Close by, we work in Ballymena, about 10.4 miles away, and Newtownabbey, about 12.7 miles away.
- Single-storey rear extension in Ballymena
- Single-storey rear extension in Newtownabbey
- Single-storey rear extension in Belfast
- Single-storey rear extension in Lisburn
- Single-storey rear extension in Magherafelt
Other work in Antrim:
FAQ
Single-storey rear extension questions in Antrim
Is the site visit in Antrim free?
Yes. We visit, measure up and talk through the options with no cost and no obligation.
Who will build my extension?
Vetted building teams working under contract to us. Your contract is with S&K Property Investments and Improvement Ltd for the design and the build.
Will the extension make the room behind it dark?
Not if it is designed well. Rooflights or a lantern over the old back room, and a wide opening into it, keep daylight reaching the middle of the house.
Do I need a party wall agreement?
Northern Ireland has no Party Wall Act; we agree any shared-wall work with your neighbour in writing.
Can I live at home while the extension is built?
Usually yes. Most of the work is outside until the back wall is opened near the end, and that stage is screened off.
Can I get a price without a visit?
Our online guide-price tool gives a range in a couple of minutes. A written price needs a survey.