Timber frame extensions across Castlereagh
A timber frame extension in Castlereagh starts with the right design and the right approval route. We take care of both, then build it with our own project management.
- Guide price in CastlereaghFrom £18,000 inc VAT
- PlanningNI permitted development (rear 3–4 m) or planning
- Build time8–14 weeks on site
- Postcode districtsBT1, BT2, BT4, BT5, BT6
Planning and approvals in Castlereagh
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 Castlereagh 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.
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.
When a timber frame extension makes sense
- Sites where weight or speed matters
- Homeowners who want strong energy performance
- Contemporary designs with timber or board cladding
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.
What should I budget for a timber frame extension in Castlereagh?
For Castlereagh 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 Castlereagh: £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.
Working in Castlereagh
Postcode districts we cover around Castlereagh include BT1, BT2, BT4, BT5, BT6, BT7. We also work in nearby Belfast (2 miles), Newtownabbey (6 miles), Lisburn (7 miles), Carrickfergus (10 miles).
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 happens next
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 draw the design, agree it with you and handle planning or permitted development checks and building regulations.
Fixed written price
The price is fixed in writing once the design is settled, with a clear programme and payment stages.
Build and sign-off
Our team builds the extension, keeps you updated weekly and finishes with building control sign-off.
Timber frame extension questions answered
How long does a timber frame extension take to build in Castlereagh?
On site, typically 8 to 14 weeks once approvals are in place. Before that, allow 4–12 weeks design and approvals.
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Castlereagh, 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 Castlereagh?
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.
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.
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.
Book a free site visit in Castlereagh
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.