Derry/Londonderry over-garage extensions, designed and built
Derry/Londonderry homeowners can use us for the whole over-garage extension project: survey, design, planning or permitted development checks, building regulations and the build itself.
- Guide price in Derry/LondonderryFrom £20,500 inc VAT
- PlanningPermission from the council needed
- Build time12–18 weeks on site
- Postcode districtsBT48
Planning rules that apply in Derry/Londonderry
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 Derry/Londonderry address depends on its history and any designations, which is why we check it at the first visit.
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.
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.
Local to Derry/Londonderry
We cover Derry/Londonderry and the postcode districts BT48. Neighbouring towns we cover include Limavady (15 miles), Coleraine (27 miles), Magherafelt (31 miles).
In Northern Ireland, extension projects follow the NI planning rules and council building control, which we account for from the first survey.
What we take care of
- Structural survey of garage walls and foundations
- New floor structure, walls and roof
- Insulation, electrics, heating and finish
- Opening into the existing first floor
- Design and householder planning application
- Strengthening or rebuilding the garage walls if needed
What should I budget for an over-garage extension in Derry/Londonderry?
Prices below are for Derry/Londonderry, using the Northern Ireland factor of ×0.86. They are guide ranges including VAT for the build only, not a quote.
Typical rates in Derry/Londonderry: £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.
Our process, step by step
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
It starts with a visit to your house to measure, check access and talk through ideas and budget.
Design and approvals
Drawings are prepared and agreed with you, then submitted for the right planning route and building regulations approval.
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.
Over-garage extension questions answered
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Derry/Londonderry, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
Who do I contract with for an over-garage extension in Derry/Londonderry?
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.
Will my neighbours in Derry/Londonderry 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.
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 Derry/Londonderry
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.