First-floor extensions in Abercarn
Our first-floor extensions service in Abercarn covers everything: measured survey, design, planning or permitted development checks, structural design, building control and the build itself.
Useful details for planning a first-floor extension in Abercarn.
- Postcode districts
- NP11
- County / area
- Gwent, Wales
- Price region
- Wales
- Guide price
- £23,000–£33,500 (£1,660–£2,390 per m²)
- Approval route
- It may be permitted development if the ground floor goes no more than 4 m and the first floor no more than 3 m beyond the original rear wall, with the first floor 10.5 m from the rear boundary.
- Nearest towns
- Newbridge (1.3 miles), Crumlin (Gwent) (2.1 miles), Risca (3.1 miles)
- Distance to Newport (Gwent)
- about 7.2 miles
- First visit
- Free, no obligation
About a first-floor extension
A first-floor extension is a new upstairs room built on top of an existing single-storey part of your house, such as a rear kitchen extension, a utility or a side annexe. It adds a bedroom, bathroom or study without enlarging the footprint. Whether it works depends mainly on whether the walls and foundations below can carry the extra load.
Abercarn sits about 7.2 miles from Newport (Gwent). Closer to home, Newbridge is 1.3 miles away and Crumlin (Gwent) 2.1 miles.
What it costs in Abercarn
Our guide for Wales is £1,660–£2,390 per m² including VAT. On a project with 4 m × 3.5 m of new first-floor space (14 m²), that puts a first-floor extension in Abercarn at roughly £23,000–£33,500. Kitchens, bathroom fittings and flooring are priced separately so you can compare like with like.
| Spec | Per m² | 4 m × 3.5 m of new first-floor space (14 m²) |
|---|---|---|
| Essential | £1,520–£2,200 per m² | £21,500–£31,000 |
| Standard | £1,660–£2,390 per m² | £23,000–£33,500 |
| Premium | £1,990–£2,870 per m² | £28,000–£40,000 |
Planning and building regulations in Abercarn
In Wales, a first floor over a rear extension can be permitted development if it goes no more than 3 m beyond the original rear wall and stays at least 10.5 m from the rear boundary, with the ground floor within 4 m. Over a side extension, the 10.5 m, 1 m set-back and 50% width tests apply. Otherwise a householder application costs £585.
Approval in Wales: Householder planning application: £585. Councils normally decide householder applications within 8 weeks.
Building regulations: Building regulations approval under the Welsh Approved Documents, which differ from England's in places (notably energy efficiency).
Design points for Abercarn homes
Tying into the house
The new floor and walls must line up with the existing first floor, often through a new opening in the rear wall above the old one. Floor levels, the position of upstairs windows and the existing roof all affect where the opening can go, so we survey both floors carefully.
Can the existing structure take it?
Many single-storey extensions were built with foundations, walls and lintels sized for one storey. We find out what is there with trial holes and, where available, the original building control drawings. The engineer then decides whether to reuse, strengthen or rebuild parts of the structure.
How we'd run your project
Free site visit
We visit your home in Abercarn, look at the structure, access and boundaries, and talk through what you want the new rooms to do.
Design and approvals
We draw the extension and check it against the rules for Wales, then apply for planning permission or a certificate of lawfulness, whichever fits.
Structure and building control
A structural engineer sizes the foundations and steels, and we get building regulations approval before work starts.
On site
One project lead runs the job, keeps you updated and arranges inspections at each stage until completion.
Questions about first-floor extensions in Abercarn
Which postcodes do you cover around Abercarn?
We cover Abercarn (NP11) and nearby places including Newbridge, Crumlin (Gwent) and Risca, plus the rest of Gwent. The first site visit is free.
Do I need planning permission for a first-floor extension in Abercarn?
Abercarn is in Wales, so Wales planning rules apply. It may be permitted development if the ground floor goes no more than 4 m and the first floor no more than 3 m beyond the original rear wall, with the first floor 10.5 m from the rear boundary. If in doubt, a lawful development certificate or a planning application gives you certainty before you build.
How much does a first-floor extension cost in Abercarn?
Our guide for Wales, which covers Abercarn, is £1,660–£2,390 per m² including VAT. A typical project with 4 m × 3.5 m of new first-floor space (14 m²) comes to about £23,000–£33,500. Design and approval fees are extra, and we fix the build price in writing once the design is agreed.
What happens to the room below while the first floor is built?
The old roof is removed, so the room below is exposed for a short period. We fit temporary weather protection, plan the work so the roof comes off only when the new structure is ready, and agree with you which rooms will be out of use and for roughly how long.
Can I build on top of my existing single-storey extension?
Often yes, but only after the structure has been checked. Foundations, walls and lintels built for one storey may not carry two. We dig trial holes, look for the original building control approval and ask the structural engineer to confirm what can stay, what needs strengthening and what must be rebuilt.
Nearby
We also cover places near Abercarn, including:
Other extensions in Abercarn
- Rear
- Side
- Wraparound
- Part two-storey
- Over a garage
- Semi-detached
- Detached
- Kitchen and bedrooms
- Bedroom and en-suite
All two-storey extension services in Abercarn · First-floor extensions across Gwent
Want a figure first? Try our guide price tool, then book a free visit to firm it up.