Timber frame extensions in Derry/Londonderry: design, approvals and build
From the first sketch to final sign-off, we plan and build timber frame extensions in Derry/Londonderry and the surrounding County Londonderry area.
- Guide price in Derry/LondonderryFrom £18,000 inc VAT
- PlanningNI permitted development (rear 3–4 m) or planning
- Build time8–14 weeks on site
- Postcode districtsBT48

What we take care of
- Cladding, render or brick slip finish
- Frame design and structural calculations
- Breathable wall build-up with insulation
- Fire and acoustic details where needed
- Foundations, often lighter than masonry
Moisture is the enemy of any timber building. We design ventilated cladding cavities, breather membranes and a proper damp-proof course height, and keep the frame dry during construction.
Do I need planning permission 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.
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.
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.
What should I budget for a timber frame extension in Derry/Londonderry?
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 Derry/Londonderry: £1,500 to £2,920 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 3 m × 4 m 12 m² | £18,000 – £22,000 | £21,000 – £27,500 | £26,500 – £35,500 |
| 4 m × 5 m 20 m² | £30,000 – £36,500 | £35,000 – £46,000 | £44,500 – £58,500 |
| 5 m × 6 m 30 m² | £45,000 – £54,500 | £52,500 – £68,500 | £67,000 – £88,000 |
For a figure based on your own dimensions, use our guide-price tool.
Local to Derry/Londonderry
Across BT48, we can visit, measure and advise. We also work in nearby Limavady (15 miles), Coleraine (27 miles), Magherafelt (31 miles).
Just over the County Tyrone border, Strabane is about 13 miles away. In Northern Ireland, extension projects follow the NI planning rules and council building control, which we account for from the first survey.
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
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
With the design and specification agreed, you get a fixed written price and a start date.
Build and sign-off
The build is managed from start to finish, inspected at each stage and signed off on completion.
Your questions about a timber frame extension in Derry/Londonderry
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 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 a timber frame 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.
Is timber frame cheaper than brick?
It is similar overall. The frame can save time on site, but the cladding choice has a big effect on cost. Our guide range is about £1,500 to £2,920 per m² including VAT.
Does a timber frame extension need planning permission?
The same planning rules apply as for any extension. If the cladding looks different from the house, permitted development’s matching-materials condition may mean an application is needed.
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.