Home office extensions in Larne
Our design and build teams take on home office extensions in Larne, from the first measured survey through planning and building control to the finished room.
- Guide price in LarneFrom £13,500 inc VAT
- PlanningNI permitted development (rear 3–4 m) or planning
- Build time8–12 weeks on site
- Postcode districtsBT40

Will the council need to approve it?
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.
In Northern Ireland building control is run by the councils under the Building Regulations (Northern Ireland). We submit full plans or a building notice and book the inspections through to completion.
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.
Home office extension prices in Larne
These guide figures apply our Northern Ireland adjustment (×0.86) to national rates. They include VAT at 20% and cover the build itself; design and council fees are listed separately.
Typical rates in Larne: £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 |
Try the guide-price tool to see a range for your own size and finish.
Covering Larne
Site visits are available across Larne (BT40). Nearby, we also take on projects in Carrickfergus (9 miles), Newtownabbey (14 miles), Belfast (18 miles), Antrim (18 miles).
Just over the County Down border, Bangor, County Down is about 14 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?
- Homes where a loft or garden room is not practical
- Households that need a second quiet room
- People who work from home most of the week
North-facing glass and rooflights give steadier light for screen work. Where the office faces south, we use deeper reveals or external shading to keep glare and heat down.
From first visit to completion
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
A designer visits, takes measurements and photos, and discusses layouts, budget and timing with you.
Design and approvals
We produce the drawings and structural design, and manage the approvals so they are in place before work starts.
Fixed written price
With the design and specification agreed, you get a fixed written price and a start date.
Build and sign-off
We build it with one project manager, book the building control inspections and hand over the completion certificate.
Common questions in Larne
Do I need building regulations approval in Larne?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
Will my neighbours in Larne be involved?
If a planning application is needed, the council notifies neighbours. Where work is close to a shared boundary, we agree access and protection with them in writing.
How long does a home office extension take to build in Larne?
On site, typically 8 to 12 weeks once approvals are in place. Before that, allow 4–10 weeks design and approvals.
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 Larne.
Book a free site visit in Larne
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.