Carrickfergus house extensions
Every type of house extension in Carrickfergus, from single-storey kitchen extensions to two-storey additions, side returns and orangeries. We design, handle the approvals and build.
- Postcode districtsBT38
- Price regionNorthern Ireland (×0.86)
- Planning rulesNorthern Ireland
- Site visitFree, no obligation
What extensions cost in Carrickfergus
We publish guide prices so you can budget before anyone visits. For Carrickfergus they are adjusted by ×0.86, the factor we use across Northern Ireland.
| Extension type | Example size | Standard spec (inc VAT) |
|---|---|---|
| Conservatory replacement extensions | 14 m² | £25,500 – £33,500 |
| Double-storey extensions | 32 m² | £49,500 – £65,000 |
| Wraparound extensions | 25 m² | £49,000 – £62,500 |
| Kitchen extensions | 20 m² | £36,000 – £46,000 |
| Extensions over a garage | 12 m² | £21,500 – £28,000 |
| Orangery extensions | 16 m² | £38,500 – £48,500 |
| Single-storey rear extensions | 20 m² | £35,000 – £45,000 |
Choosing the right extension in Carrickfergus
Northern Ireland's housing ranges from city terraces to large numbers of detached houses and bungalows on rural plots, many in render, where single-storey extensions fit easily.
Depending on the plot, bungalow extensions and single-storey rear extensions are often the strongest options, with side extensions worth considering where there is room.
Covering Carrickfergus and nearby
Site visits are available across Carrickfergus (BT38). Neighbouring towns we cover include Newtownabbey (6 miles), Larne (9 miles), Belfast (10 miles), Castlereagh (10 miles), Lisburn (16 miles). Just over the County Down border, Bangor, County Down is about 7 miles away.
Planning rules in Carrickfergus
In Northern Ireland the Planning (General Permitted Development) Order 2015 lets some single-storey rear extensions go ahead without planning permission, up to 3 m on a semi-detached or terraced house and 4 m on a detached house, within height and boundary limits. Larger, side and two-storey extensions normally need planning permission from the council, and building control approval is separate.
In a conservation area or area of townscape character the permitted development rights are more limited, listed homes need listed building consent, and if rights have been removed by a condition, any extension needs an application.
Northern Ireland has no Party Wall Act. Where work is on or close to a shared boundary, we agree access and protection with your neighbour in writing before work starts.
Applications are decided by your council, which handles local planning in Northern Ireland.
Choose an extension type
- Kitchen extensions · from £23,000
- Extensions over a garage · from £20,500
- Side return extensions · from £15,000
- Planning permission for extensions · from £300
- Annexe extensions · from £47,000
- Double-storey extensions · from £32,500
- Home office extensions · from £13,500
- Wraparound extensions · from £30,500
- Timber frame extensions · from £18,000
- Bedroom extensions · from £22,000
- Side extensions · from £18,500
- Bungalow extensions · from £22,500
- Orangery extensions · from £25,500
- Building regulations for extensions · from £750
- Conservatory replacement extensions · from £17,000
- Pitched roof extensions · from £19,000
- Glass box extensions · from £25,500
- Extension plans and drawings · from £1,000
- Single-storey rear extensions · from £18,000
- Flat roof extensions · from £18,000
- Porch extensions · from £3,400
- Utility and boot room extensions · from £12,000
Free site visit
First, a site visit: we look at the house, garden, access and drains and listen to what you need.
Design and approvals
We draw the design, agree it with you and handle planning or permitted development checks and building regulations.
Fixed written price
The price is fixed in writing once the design is settled, with a clear programme and payment stages.
Build and sign-off
The build is managed from start to finish, inspected at each stage and signed off on completion.
Questions about extensions in Carrickfergus
How much does an extension cost in Carrickfergus?
Using our Northern Ireland factor (×0.86), a standard-spec single-storey extension of 20 m² is a guide £35,000 to £45,000 including VAT, and a 32 m² two-storey extension £49,500 to £65,000. Your written price follows the survey.
Do you handle building regulations?
Yes. We prepare the drawings and calculations, submit them and book inspections, ending with a completion certificate.
Will my neighbours need to be told?
If you apply for planning permission the council notifies neighbours, and we agree access with them in writing for work near a shared boundary.
Can I get a price before anyone visits?
Yes. This page shows guide prices adjusted for Carrickfergus, and the guide-price tool gives a range for your own size and finish in about a minute.
Book a free site visit in Carrickfergus
We will measure up, check the planning position and give you honest guide figures.
- Free, no-obligation site visit
- Planning route checked before you spend on drawings
- Written price once the design is agreed
- Building control sign-off at the end
Prefer to talk? Call 0800 088 6341 or .
Book a free site visit
Tell us a little about the project and we will arrange a time.