First-floor extensions in Steynton
Our first-floor extensions service in Steynton covers everything: measured survey, design, planning or permitted development checks, structural design, building control and the build itself.
Steynton: the key facts for this kind of project.
- Postcode districts
- SA73
- County / area
- Dyfed, 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
- Milford Haven (1.3 miles), Neyland (3.1 miles), Pembroke Dock (4.2 miles)
- Distance to Llanelli
- about 36.8 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.
We cover Steynton (SA73) and the places around it, including Milford Haven (1.3 miles), Neyland (3.1 miles) and Pembroke Dock.
What it costs in Steynton
Expect a first-floor extension in Steynton to land somewhere around £23,000–£33,500 for 4 m × 3.5 m of new first-floor space (14 m²). Our Wales guide rate is £1,660–£2,390 per m², including VAT. 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 Steynton
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 Steynton 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.
Escape and fire safety
A new first-floor bedroom needs an escape window with a clear opening of at least 0.33 m², at least 450 mm wide and 450 mm high, with the bottom no more than 1,100 mm above the floor, unless there is a protected route to the stairs.
How we'd run your project
Understand the brief
At your home in Steynton we agree what you need: bedroom count, bathroom, kitchen space, and how much garden you want to keep.
Drawings, then consent
We draw the scheme, check it against the rules in Wales, and take it through the right consent with the council.
Fixed price in writing
With approved drawings and calculations, we give you a fixed build price and a programme you can plan around.
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 Steynton
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.
How much does a first-floor extension cost in Steynton?
Our guide for Wales, which covers Steynton, 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.
Which postcodes do you cover around Steynton?
We cover Steynton (SA73) and nearby places including Milford Haven, Neyland and Pembroke Dock, plus the rest of Dyfed. The first site visit is free.
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 Steynton
- 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 Steynton · First-floor extensions across Dyfed
Want a figure first? Try our guide price tool, then book a free visit to firm it up.