Bargoed, South Wales Valleys
Single-storey rear extension in Bargoed
Single-storey rear extension in Bargoed: ground-floor space across the back of the house, usually for a kitchen, dining or family room. We measure the house, show you what the rules allow, price it in writing and build it.
Bargoed is covered from our South Wales Valleys round, including CF81. A depth of 3 to 4 metres keeps many single-storey rear extensions in Bargoed within permitted development, subject to the house's planning history.
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 single-storey rear extension cost in Bargoed?
For Bargoed we work from the Wales rate: £1,770–£2,880 per square metre of new floor, including VAT, 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 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 |
Ground conditions, glazing, the roof and how far the house is opened up move the final figure within the range.
Do you need planning permission for a single-storey rear extension in Bargoed?
Planning for a single-storey rear extension in Bargoed follows the Welsh householder rules.
The Welsh Government's householder rules let many homes add a single-storey rear extension up to 4 metres deep and 4 metres high without a planning application. Deeper projects go through a householder application, because Wales has no prior approval route.
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 Bargoed like to extend?
Stone terraces along the valley floors and post-war semis higher up are typical of Bargoed. Sloping sites are common, so floor levels and retaining walls are designed at the start.
How a single-storey rear extension in Bargoed 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.
Options and costs
We draw layout options and price each one, so the budget shapes the design rather than surprising you later.
Planning and regulations
We take the design through the right planning route, then produce the construction drawings and engineer's calculations for building control.
Build and sign-off
We build to the approved drawings with regular updates, then hand over the building control completion certificate and any guarantees from suppliers.
Single-storey rear extensions near Bargoed
Neighbouring places we cover include Blackwood (1.5 miles) and Gelligaer (1.6 miles).
- Single-storey rear extension in Blackwood
- Single-storey rear extension in Gelligaer
- Single-storey rear extension in Nelson
- Single-storey rear extension in Treharris
- Single-storey rear extension in Abercarn
Other work in Bargoed:
FAQ
Single-storey rear extension questions in Bargoed
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.
Do you handle building control in Bargoed?
Yes. We apply to the council or a registered approver under the Welsh regulations and hand over the completion certificate.
Does it add value to the house?
Nationwide's October 2025 house price research found that a 10% increase in floor area is linked to about 5% higher value on average. It is a guide, not a promise; local agents can tell you what extended homes on your street sell for.
Can you match the brick or stone on my Bargoed house?
We source the closest match and show you samples before ordering; reclaimed materials are often the best match on older houses.
How long does a rear extension take to build in Bargoed?
Most single-storey rear extensions take 10 to 16 weeks on site and two-storey extensions 16 to 26 weeks, after design and approvals.
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.