Cwmbran, South Wales Valleys
Two-storey rear extension in Cwmbran
A larger kitchen downstairs and an extra bedroom or bathroom upstairs, under one roof. We design, get the approvals for and build two-storey rear extensions in Cwmbran and the surrounding area, with one contract from the first survey to building control sign-off.
Cwmbran is covered from our South Wales Valleys round, including NP44. In Cwmbran, a two-storey rear extension is worth comparing with the cost of moving once stamp duty, agents' and legal fees are counted.
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 two-storey rear extension cost in Cwmbran?
In Cwmbran, our guide for a two-storey rear extension is £1,670–£2,510 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 × 5 m footprint, two floors (30 m²) | £50,000–£75,500 |
| 4 m × 6 m footprint, two floors (48 m²) | £80,500–£120,500 |
Your written price follows a measured survey and an agreed design, so it reflects your house, not an average.
Do you need planning permission for a two-storey rear extension in Cwmbran?
Here is how the rules in Wales apply to a two-storey rear extension in Cwmbran.
In Wales a rear extension of more than one storey can be permitted development if the ground floor projects no more than 4 metres and the upper floor no more than 3 metres, with at least 10.5 metres to the rear boundary. It is not permitted development in conservation areas, National Parks or National Landscapes, so many double-storey schemes need a householder application.
Conservation areas, National Parks and National Landscapes restrict permitted development in Wales, and listed buildings need listed building consent. At the first visit we measure what is there now and tell you which route fits: permitted development or a householder planning application.
What are homes in Cwmbran like to extend?
Cwmbran 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 two-storey rear extension in Cwmbran comes together
Free site visit
We measure the house and garden, look at the back wall, drainage and boundaries, and talk through what you want from the space.
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.
Two-storey rear extensions near Cwmbran
Neighbouring places we cover include Pontypool (3.4 miles) and Caerleon (4.3 miles).
- Two-storey rear extension in Pontypool
- Two-storey rear extension in Caerleon
- Two-storey rear extension in Risca
- Two-storey rear extension in Newport
- Two-storey rear extension in Abercarn
Other work in Cwmbran:
FAQ
Two-storey rear extension questions in Cwmbran
Do you handle building control in Cwmbran?
Yes. We apply to the council or a registered approver under the Welsh regulations and hand over the completion certificate.
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 add an en-suite upstairs?
Yes. We plan the soil pipe route early so the bathroom sits where drainage works without boxing through the room below.
How much does a two-storey rear extension cost in Cwmbran?
As a guide, £1,670–£2,510 per square metre including VAT for a standard specification. For example, 3 m × 5 m footprint, two floors (30 m²): about £50,000–£75,500 at that rate. Your written price follows the survey.
What postcode areas do you cover around Cwmbran?
Including NP44, and the surrounding South Wales Valleys area.
How long does a rear extension take to build in Cwmbran?
Most single-storey rear extensions take 10 to 16 weeks on site and two-storey extensions 16 to 26 weeks, after design and approvals.