Extensions over a garage in County Antrim
Our design and build teams take on over-garage extensions in County Antrim, from the first measured survey through planning and building control to the finished room.
- Guide priceFrom £20,500 inc VAT
- PlanningPermission from the council needed
- Towns covered8
- Site visitFree, no obligation
Towns in County Antrim
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.
Homes in conservation areas, areas of townscape character and listed buildings have tighter rules, so we always check the property's status and planning history before design starts.
Building close to a public sewer needs the agreement of NI Water, which we check during design.
Applications are decided by your council, which handles local planning in Northern Ireland.
Over-garage extension prices in County Antrim
For County Antrim we adjust our national guide rates by ×0.86, the factor we use for Northern Ireland. Figures include VAT; your written quote after the survey replaces them.
Typical rates in County Antrim: £1,550 to £2,920 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| Over a single garage 12 m² | £20,500 – £25,500 | £21,500 – £28,000 | £27,500 – £35,500 |
| Over a large single garage 16 m² | £24,500 – £30,500 | £28,500 – £37,500 | £37,000 – £47,000 |
| Over a double garage 24 m² | £37,000 – £45,500 | £43,000 – £56,000 | £55,500 – £70,500 |
For a figure based on your own dimensions, use our guide-price tool.
Covering County Antrim
Towns we cover in County Antrim include Belfast, Lisburn, Newtownabbey, Castlereagh, Carrickfergus, Ballymena, Antrim, Larne. 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.
What we take care of
- Design and householder planning application
- Opening into the existing first floor
- Insulation, electrics, heating and finish
- New floor structure, walls and roof
- Strengthening or rebuilding the garage walls if needed
- Structural survey of garage walls and foundations
Fitting the new room to the existing landing is the planning puzzle inside the house. We design the connection first, then the roof, so the extension does not end up with awkward steps or a corridor through a bedroom.
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
A designer visits, takes measurements and photos, and discusses layouts, budget and timing with you.
Design and approvals
Once the layout is agreed, we deal with the council: planning permission or written confirmation that none is needed, plus building control.
Fixed written price
With the design and specification agreed, you get a fixed written price and a start date.
Build and sign-off
Our team builds the extension, keeps you updated weekly and finishes with building control sign-off.
Your questions about an over-garage extension in County Antrim
How long does an over-garage extension take to build in County Antrim?
On site, typically 12 to 18 weeks once approvals are in place. Before that, allow 8–14 weeks design and approvals.
Who do I contract with for an over-garage extension in County Antrim?
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.
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for County Antrim, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
Can I keep using the garage during the build?
Usually not for parking. The garage roof is removed and the space below is used for access and props for part of the build.
Can my garage take the weight of a room on top?
Some can and some cannot. Many garages have a single-skin wall or shallow foundations. Our structural engineer checks this before we give a fixed price.
Book a free site visit in County Antrim
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.