Carrickfergus home office extensions, designed and built
From the first sketch to final sign-off, we plan and build home office extensions in Carrickfergus and the surrounding County Antrim area.
- Guide price in CarrickfergusFrom £13,500 inc VAT
- PlanningNI permitted development (rear 3–4 m) or planning
- Build time8–12 weeks on site
- Postcode districtsBT38
Local to Carrickfergus
We cover Carrickfergus and the postcode districts BT38. Nearby, we also take on projects in Newtownabbey (6 miles), Larne (9 miles), Belfast (10 miles), Castlereagh (10 miles).
For homes towards County Down, Bangor, County Down is around 7 miles away. In Northern Ireland, extension projects follow the NI planning rules and council building control, which we account for from the first survey.
Is a home office extension right for your house?
- Households that need a second quiet room
- Homes where a loft or garden room is not practical
- People who work from home most of the week
Planning rules that apply 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.
The planning position for a specific Carrickfergus address depends on its history and any designations, which is why we check it at the first visit.
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.
Guide prices for Carrickfergus
Labour and material costs vary across the UK, so for Carrickfergus we use our Northern Ireland factor (×0.86). The ranges include VAT and exclude design, structural and council fees.
Typical rates in Carrickfergus: £1,590 to £2,920 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 2.5 m × 3.2 m 8 m² | £13,500 – £16,500 | £14,500 – £19,000 | £18,500 – £23,500 |
| 3 m × 3.6 m 11 m² | £17,500 – £21,000 | £20,000 – £26,000 | £25,500 – £32,500 |
| 3 m × 5 m 15 m² | £23,500 – £28,500 | £27,500 – £35,000 | £34,500 – £44,000 |
For a figure based on your own dimensions, use our guide-price tool.
How the project works
Site visits are free and there is no obligation. Where drawings are needed, the design stage is priced in writing before it starts.
Free site visit
We visit your Carrickfergus home, measure up, talk through what you want and check the planning position.
Design and approvals
We draw the design, agree it with you and handle planning or permitted development checks and building regulations.
Fixed written price
You receive a written, itemised price and programme. Nothing starts until you are happy with it.
Build and sign-off
Our team builds the extension, keeps you updated weekly and finishes with building control sign-off.
Questions people ask about home office extensions
Who do I contract with for a home office extension in Carrickfergus?
Your contract is with S&K Property Investments and Improvement Ltd, which designs and manages the project and the build teams who carry it out.
How long does a home office extension take to build in Carrickfergus?
On site, typically 8 to 12 weeks once approvals are in place. Before that, allow 4–10 weeks design and approvals.
Do you cover all of Carrickfergus?
Yes. We cover Carrickfergus and the surrounding parts of County Antrim. Site visits are free and there is no obligation.
Can I claim the cost against tax?
Building work on your home is not normally an allowable business expense, and claiming it can have capital gains tax effects. Speak to an accountant before assuming any tax relief.
How much does a home office extension cost?
Our guide range is about £1,590 to £2,920 per m² including VAT. An 11 m² standard-spec office is typically £20,000 to £26,000 in Carrickfergus.
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.