Brynmawr · Gwent

Two-storey rear extensions in Brynmawr

For a two-storey rear extension in Brynmawr, the first questions are always the same: how big, which approvals, and what it will cost. This page answers all three for Gwent.

Quick reference for homeowners in Brynmawr.

Postcode districts
NP23
County / area
Gwent, Wales
Price region
Wales
Guide price
£51,500–£69,500 (£1,840–£2,480 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
Ebbw Vale (1.9 miles), Tredegar (3.3 miles), Gilwern (4.2 miles)
Distance to Newport (Gwent)
about 16.7 miles
First visit
Free, no obligation

About a two-storey rear extension

A two-storey rear extension suits you if you need more room on both floors and have a reasonably deep garden. You get one team for the whole job: a measured survey, the design, a check on whether permitted development applies, planning drawings where they are needed, structural design, building regulations approval and the build itself, carried out by vetted teams working under S&K. Every project starts with a free site visit.

Brynmawr sits about 16.7 miles from Newport (Gwent). Closer to home, Ebbw Vale is 1.9 miles away and Tredegar 3.3 miles.

What it costs in Brynmawr

Most of the cost of a two-storey rear extension is set by its size and specification. For Brynmawr and the rest of Wales, our guide is £1,840–£2,480 per m² including VAT, so about £51,500–£69,500 for a 4 m × 3.5 m footprint on two floors (28 m² of new floor space). Professional fees for drawings and the structural engineer are listed separately on our prices page.

SpecPer m²A 4 m × 3.5 m footprint on two floors (28 m² of new floor space)
Essential£1,690–£2,290 per m²£47,500–£64,000
Standard£1,840–£2,480 per m²£51,500–£69,500
Premium£2,210–£2,980 per m²£62,000–£83,500

Planning and building regulations in Brynmawr

In Wales, a two-storey rear extension can 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 at least 10.5 m from the rear boundary. Nothing within 2 m of a boundary can be higher than 4 m. Conservation areas and other protected areas are excluded, and 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 Brynmawr homes

Foundations and drains

Foundations for two storeys carry more load than a single storey and may need to go deeper near trees or on clay. Rear extensions often sit near drains, so we check sewer records early, as building over or near a public sewer may need the water company's agreement.

Upstairs layout and windows

Bedrooms above need a window big enough for escape or a protected route to the stairs. Side-facing upstairs windows normally have to be obscure-glazed and fixed below 1.7 m, so we put the main bedroom windows in the rear wall and use roof lights where extra daylight is needed.

How we'd run your project

  1. Understand the brief

    At your home in Brynmawr we agree what you need: bedroom count, bathroom, kitchen space, and how much garden you want to keep.

  2. Drawings and permission

    Our designers produce plans and elevations, then we take care of planning or permitted development checks with the council covering Brynmawr.

  3. Fixed price in writing

    With approved drawings and calculations, we give you a fixed build price and a programme you can plan around.

  4. Build it

    The new structure goes up first, then we open into the house, finish inside and get the completion certificate.

Questions about two-storey rear extensions in Brynmawr

Which postcodes do you cover around Brynmawr?

We cover Brynmawr (NP23) and nearby places including Ebbw Vale, Tredegar and Gilwern, plus the rest of Gwent. The first site visit is free.

How much does a two-storey rear extension cost in Brynmawr?

Our guide for Wales, which covers Brynmawr, is £1,840–£2,480 per m² including VAT. A typical project with a 4 m × 3.5 m footprint on two floors (28 m² of new floor space) comes to about £51,500–£69,500. Design and approval fees are extra, and we fix the build price in writing once the design is agreed.

Who handles building regulations for a project in Brynmawr?

We handle it as part of the project. What's needed in Wales: building regulations approval under the Welsh Approved Documents, which differ from England's in places (notably energy efficiency). We prepare the drawings and the engineer's calculations, book the inspections and pass you the completion paperwork at the end.

How long does a two-storey rear 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.

Will a two-storey rear extension block my neighbour's light?

It can if it is too deep or too close to the boundary, which is why councils look closely at its effect on neighbouring windows and gardens. We test the design against light and outlook early, keep the first floor shorter or set in where needed, and use a hipped roof to reduce bulk on the boundary side.

Nearby

The same service in neighbouring towns:

Other extensions in Brynmawr

All two-storey extension services in Brynmawr · Two-storey rear extensions across Gwent

Ready to talk it through? Call us or send the form and we'll arrange a visit to your home in Brynmawr.

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