Aberdare, South Wales Valleys
Semi-detached rear extension in Aberdare
Thinking about a semi-detached rear extension in Aberdare? Single or two-storey extensions for semi-detached houses, with side access and one party wall. Our team handles the drawings, the planning route and the build, and your contract is with one company throughout.
Aberdare is covered from our South Wales Valleys round, including CF44. Where an Aberdare semi already has a small lean-to at the back, we usually replace it rather than extend it.
Book a free site visit
Tell us about the house and we'll call to arrange a free, no-obligation visit.
How much does a semi-detached rear extension cost in Aberdare?
Guide prices for a semi-detached rear extension in Aberdare start from our Wales rate of £1,770–£2,880 per square metre, including VAT. Prices in Wales sit below our West Midlands baseline; sloping sites are the main variable.
| Size | Guide price inc VAT |
|---|---|
| 3 m wide × 4 m deep (12 m²) | £21,000–£34,500 |
| 4 m wide × 5 m deep (20 m²) | £35,500–£57,500 |
| 4 m wide × 6 m deep (24 m²) | £42,500–£69,000 |
These are guide ranges; the written quote after the survey is the figure that counts.
Do you need planning permission for a semi-detached rear extension in Aberdare?
Whether your semi-detached rear extension in Aberdare needs a planning application depends on its size, your house and any local restrictions.
Welsh permitted development allows a single-storey rear extension of up to 4 metres in depth and 4 metres in height, subject to boundary and garden-coverage limits. There is no larger-extension prior approval scheme in Wales.
Welsh rules allow a two-storey rear extension without an application only where the ground floor is no deeper than 4 metres, the upper floor no deeper than 3 metres and at least 10.5 metres remains to the rear boundary. Most homeowners still apply for householder planning permission.
Conservation areas, National Parks and National Landscapes restrict permitted development in Wales, and listed buildings need listed building consent. We check your house's planning history and any conservation area before drawing, so the route is clear before you spend on plans.
What are homes in Aberdare like to extend?
Stone terraces along the valley floors and post-war semis higher up are typical of Aberdare. Sloping sites are common, so floor levels and retaining walls are designed at the start.
How a semi-detached rear extension in Aberdare comes together
Look round and measure
A free visit to see the back of the house, measure it, check the drains and boundaries and hear what you need.
Options and costs
We draw layout options and price each one, so the budget shapes the design rather than surprising you later.
Paperwork handled
Planning or permitted development, Building Regulations approval, structural design and party wall notices are all handled by us.
Written price, then build
Once the design and approvals are in place, you get a fixed written price and programme, and we build through to sign-off.
Semi-detached rear extensions near Aberdare
We also build rear extensions for semi-detached houses in nearby Mountain Ash (3.6 miles) and Rhondda (3.8 miles).
- Semi-detached rear extension in Mountain Ash
- Semi-detached rear extension in Rhondda
- Semi-detached rear extension in Merthyr Tydfil
- Semi-detached rear extension in Tonypandy
- Semi-detached rear extension in Treharris
Other work in Aberdare:
FAQ
Semi-detached rear extension questions in Aberdare
Do you handle building control in Aberdare?
Yes. We apply to the council or a registered approver under the Welsh regulations and hand over the completion certificate.
Will I need a structural engineer?
Yes for the beam over the new opening and usually the foundations; we arrange them and their calculations go to building control.
Do I need a party wall agreement?
Usually with the attached neighbour, in England and Wales.
Who will build my extension?
Vetted building teams working under contract to us. Your contract is with S&K Property Investments and Improvement Ltd for the design and the build.
Do I need a party wall agreement?
In Wales, usually yes if the extension is on or near a shared boundary or close to a neighbour's foundations. We serve the notices.
Can I live at home while the extension is built?
Usually yes. Most of the work is outside until the back wall is opened near the end, and that stage is screened off.