Caerphilly, South Wales Valleys
Terraced house rear extension in Caerphilly
Thinking about a terraced house rear extension in Caerphilly? Rear and side return extensions for terraces, with access through the house and two neighbours. Our team handles the drawings, the planning route and the build, and your contract is with one company throughout.
Caerphilly and its postcode districts CF83 are part of our South Wales Valleys coverage. On a Caerphilly terrace both neighbours usually need party wall notices or agreement, so we talk to them early.
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 terraced house rear extension cost in Caerphilly?
In Caerphilly, our guide for a terraced house rear extension is £1,910–£3,070 per square metre including VAT for a standard specification. Prices in Wales sit below our West Midlands baseline; sloping sites are the main variable.
| Size | Guide price inc VAT |
|---|---|
| 3 m wide × 4.5 m deep (13.5 m²) | £25,500–£41,500 |
| 3 m wide × 6 m deep (18 m²) | £34,500–£55,000 |
We put a fixed price in writing once the design is agreed, and explain any provisional sums such as foundations.
Do you need planning permission for a terraced house rear extension in Caerphilly?
The planning route for a terraced house rear extension in Caerphilly is set by Wales's householder rules and your council.
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.
The Party Wall etc. Act 1996 also applies in Wales: two months' notice for work to a shared wall and one month for foundations dug close to a neighbour's building.
Conservation areas, National Parks and National Landscapes restrict permitted development in Wales, and listed buildings need listed building consent. Before any drawing we look up the property's history with the council, because earlier extensions and removed rights change the answer.
What are homes in Caerphilly like to extend?
Caerphilly is largely terraced streets on sloping ground, where back gardens step up or down from the house. Excavation, retaining walls and drainage are priced at the survey.
How a terraced house rear extension in Caerphilly comes together
Survey visit
We visit free of charge, measure up, check access, drainage and neighbours' extensions, and note what you want the room to do.
Drawings and budget
Floor plans and elevations for the options, each with a guide price.
Approvals
Permitted development check or householder planning application, then Building Regulations drawings to the Welsh Approved Documents and structural calculations, plus party wall notices where they apply.
Fixed price and build
A written price for the agreed design, a start date and a named contact through the build, ending with the building control completion certificate.
Terraced house rear extensions near Caerphilly
We also build rear extensions for terraced houses in nearby Rhiwbina (3.2 miles) and Whitchurch (4.3 miles).
- Terraced house rear extension in Rhiwbina
- Terraced house rear extension in Whitchurch
- Terraced house rear extension in Risca
- Terraced house rear extension in Pontypridd
- Terraced house rear extension in Nelson
Other work in Caerphilly:
FAQ
Terraced house rear extension questions in Caerphilly
Do I need planning permission for a rear extension in Caerphilly?
Often not for a single-storey rear extension of up to 4 metres under Welsh permitted development. Wales has no prior approval route for deeper extensions.
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 you build without side access?
Yes. Materials come through the house in protected runs or over the roof by crane on tight sites.
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 you handle building control in Caerphilly?
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.