First-floor extensions in Brecon
For a first-floor extension in Brecon, the first questions are always the same: how big, which approvals, and what it will cost. This page answers all three for Powys.
Quick reference for homeowners in Brecon.
- Postcode districts
- LD3
- County / area
- Powys, 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
- Brynmawr (13.4 miles), Tredegar (13.4 miles), Rhymney (13.6 miles)
- Distance to Newtown
- about 39.6 miles
- First visit
- Free, no obligation
About a first-floor extension
A first-floor extension suits you if your house already has a single-storey extension and you need more space upstairs. You get a structural check of the existing walls and foundations, a design that ties the new floor into the house, the approvals your nation needs, building regulations approval and the build, managed by us and carried out by vetted teams working under S&K.
Around Brecon we also work in Brynmawr, Tredegar and Rhymney, and across the rest of Powys. Postcode district in and near Brecon: LD3.
What it costs in Brecon
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 Brecon at roughly £23,000–£33,500. We'll give you a written design-stage price first, then a fixed build price once the drawings are agreed.
| 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 Brecon
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 Brecon homes
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.
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.
How we'd run your project
Look at the house
We start in Brecon with a free visit: measurements, photos, a look at the loft and drains, and a frank chat about budget.
Plans, then approval
Measured survey, design, then the right approval route for your house. We explain each step before we take it.
Structure and building control
A structural engineer sizes the foundations and steels, and we get building regulations approval before work starts.
Build and hand over
We manage the build from groundworks to decoration-ready finish and hand over with the completion paperwork.
Questions about first-floor extensions in Brecon
Which postcodes do you cover around Brecon?
We cover Brecon (LD3) and nearby places including Brynmawr, Tredegar and Rhymney, plus the rest of Powys. The first site visit is free.
How long does a first-floor extension take?
Allow 4 to 8 weeks for survey and design, then the approval period (councils normally decide householder applications within 8 weeks), then 4 to 8 weeks of technical design, which can overlap. The build itself usually takes 14 to 20 weeks, longer for large or complex designs.
Do I need planning permission for a first-floor extension in Brecon?
Brecon 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.
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
The same service in neighbouring towns:
Other extensions in Brecon
- 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 Brecon · First-floor extensions across Powys
Want a figure first? Try our guide price tool, then book a free visit to firm it up.