Ebbw Vale · Gwent

Two-storey extensions for semi-detached houses in Ebbw Vale

We cover Ebbw Vale and the rest of Gwent for two-storey extensions for semi-detached houses. Start with a free site visit and a plain-English view of what your house and plot can take.

Useful details for planning a two-storey extension for a semi-detached house in Ebbw Vale.

Postcode districts
NP23
County / area
Gwent, Wales
Price region
Wales
Guide price
£51,500–£69,500 (£1,840–£2,480 per m²)
Approval route
Depends on position: rear (3 m first floor, 10.5 m to the boundary) and some side extensions (10.5 m, 1 m set-back) can be permitted development in Wales.
Nearest towns
Tredegar (1.7 miles), Brynmawr (1.9 miles), Rhymney (3.5 miles)
Distance to Newport (Gwent)
about 15.9 miles
First visit
Free, no obligation

About a two-storey extension for a semi-detached house

A two-storey extension for a semi-detached house is a two-floor addition to the rear, the open side, or both, designed around the attached neighbour on one side. The rear is often the simplest option and can sometimes be permitted development, while a side extension uses the gap on the detached side. Both need care with the shared party wall and the neighbour's light.

Around Ebbw Vale we also work in Tredegar, Brynmawr and Rhymney, and across the rest of Gwent. Postcode district in and near Ebbw Vale: NP23.

What it costs in Ebbw Vale

Most of the cost of a two-storey extension for a semi-detached house is set by its size and specification. For Ebbw Vale 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). The fastest way to a firmer number is a free site visit, after which we price the design stage in writing.

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 Ebbw Vale

In Wales, a semi can take a two-storey rear extension under permitted development with the ground floor up to 4 m and the first floor up to 3 m beyond the original rear wall, 10.5 m from the rear boundary. A side extension can also be permitted development if it is 10.5 m from the side boundary, set back 1 m and adds no more than 50% width. Otherwise the fee is £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 Ebbw Vale homes

Keeping the pair balanced

Semis are designed as matching pairs, and a side extension changes that balance. Setting the side extension back from the front wall and keeping its ridge lower helps the pair still read as a pair, which councils' design guides commonly ask for.

Rear, side or both

On a semi, a rear extension sits against the attached neighbour, while a side extension faces the detached neighbour and the street. We compare the space, cost and approval route for each, and for a wraparound, before you commit to one design.

How we'd run your project

  1. Free site visit

    We visit your home in Ebbw Vale, look at the structure, access and boundaries, and talk through what you want the new rooms to do.

  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. Finish and certify

    Second fix, plastering and making good, then building control's final inspection and the completion paperwork.

Questions about two-storey extensions for semi-detached houses in Ebbw Vale

How much does a two-storey extension for a semi-detached house cost in Ebbw Vale?

Our guide for Wales, which covers Ebbw Vale, 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.

Which postcodes do you cover around Ebbw Vale?

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

How long does a two-storey extension for a semi-detached house 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.

What if my neighbour has already extended?

That often helps. An existing extension next door can reduce the effect of yours on their light, and may show what the council accepts on your street. It can also mean building alongside their wall, so we check its position, foundations and any windows facing your plot at the survey.

Will a side extension make my semi look like a terrace?

It can if it fills the whole gap to the boundary at first floor and the neighbour does the same. Many councils ask for a first-floor gap to the side boundary or a set-back for this reason. We design the extension to keep the semi reading as one of a pair.

Nearby

Other towns near Ebbw Vale:

Other extensions in Ebbw Vale

All two-storey extension services in Ebbw Vale · Two-storey extensions for semi-detached houses across Gwent

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

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