Brynmawr · Gwent

Part single, part two-storey extensions in Brynmawr

Adding a part single, part two-storey extension in Brynmawr gives you two new rooms stacked on one footprint. Here's how we'd approach it, what it typically costs and the rules that apply in Wales.

Quick reference for homeowners in Brynmawr.

Postcode districts
NP23
County / area
Gwent, Wales
Price region
Wales
Guide price
£66,000–£91,000 (£1,840–£2,530 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 part single, part two-storey extension

A part single, part two-storey extension suits you if you want a generous ground floor but only need one extra room upstairs, or if a full two-storey design would affect a neighbour too much. You get design options that test where the two-storey part works best, the approvals your nation needs, structural design, building regulations approval and the build, carried out by vetted teams working under S&K.

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

A guide price for Brynmawr: around £66,000–£91,000 for a 6 m × 4 m ground floor and a first floor over half of it (36 m² in total). That works out at £1,840–£2,530 per m² of new floor space, including VAT at 20%. The fastest way to a firmer number is a free site visit, after which we price the design stage in writing.

SpecPer m²A 6 m × 4 m ground floor and a first floor over half of it (36 m² in total)
Essential£1,690–£2,330 per m²£61,000–£84,000
Standard£1,840–£2,530 per m²£66,000–£91,000
Premium£2,210–£3,040 per m²£79,500–£109,500

Planning and building regulations in Brynmawr

In Wales, a part two-storey rear extension can be permitted development if the first floor goes no more than 3 m and the ground floor no more than 4 m beyond the original rear wall, with the first floor at least 10.5 m from the rear boundary. Conservation areas and other protected areas are excluded. If the design falls outside these limits, 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

Structure at the step

The first-floor wall above often sits over the new open-plan space, so it needs a steel beam or frame to carry it. Loads come down at different points than in a full two-storey design, and the engineer sizes the foundations to suit each part.

Where to put the two-storey part

The two-storey section usually works best away from the closest neighbour, with the single-storey part on that boundary side. We test a few positions against neighbours' windows, the upstairs layout and the roof shape before choosing the one to take forward.

How we'd run your project

  1. Look at the house

    We start in Brynmawr with a free visit: measurements, photos, a look at the loft and drains, and a frank chat about budget.

  2. 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.

  3. Detail and price

    Construction drawings, engineer's calculations and building control sign-off, then a written fixed price for the build.

  4. On site

    One project lead runs the job, keeps you updated and arranges inspections at each stage until completion.

Questions about part single, part two-storey extensions in Brynmawr

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.

Do I need planning permission for a part single, part two-storey extension in Brynmawr?

Brynmawr 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 long does a part single, part two-storey 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.

Which side should the two-storey part go on?

Usually the side furthest from the nearest neighbour's windows, so the single-storey part sits nearest them and keeps their light. Other factors are where the stairs land upstairs, which room needs the extra space and where drains run. We sketch options at the design stage and explain which is most likely to be approved.

Can the single-storey part be deeper than the two-storey part?

With planning permission, yes, and that is often the point of the design: the ground floor projects further into the garden while the first floor stays back from neighbours. Under permitted development, the depth limits for extensions of more than one storey can apply to the whole extension, so we confirm which route applies before drawings are finalised.

Nearby

Close to Brynmawr? We work across the area, including:

Other extensions in Brynmawr

All two-storey extension services in Brynmawr · Part single, part two-storey extensions across Gwent

The quickest next step is a visit. We'll look at your house in Brynmawr and give you an honest view of the options.

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