Two-storey extensions for detached houses in Crumlin (Gwent)

Crumlin (Gwent): the key facts for this kind of project.

Postcode districts: NP11
County / area: Gwent, Wales
Price region: Wales
Guide price: £79,000–£106,500 (£1,890–£2,530 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: Newbridge (0.8 miles), Abercarn (2.1 miles), Blackwood (3.2 miles)
Distance to Newport (Gwent): about 8.6 miles
First visit: Free, no obligation

About a two-storey extension for a detached house

This service suits you if you own a detached house and want a substantial amount of extra space, whether a side extension over a drive, a rear extension into the garden or a wraparound. You get a survey of the whole plot, options that compare layouts and costs, the approvals your nation needs, structural design and the build, carried out by vetted teams working under S&K.

Crumlin (Gwent) sits about 8.6 miles from Newport (Gwent). Closer to home, Newbridge is 0.8 miles away and Abercarn 2.1 miles.

What it costs in Crumlin (Gwent)

In Wales, which includes Crumlin (Gwent), we'd expect a two-storey extension for a detached house to cost around £79,000–£106,500 for a 3 m × 7 m footprint on two floors (42 m² of new floor space), or £1,890–£2,530 per m² including VAT. The fastest way to a firmer number is a free site visit, after which we price the design stage in writing.

Spec	Per m²	A 3 m × 7 m footprint on two floors (42 m² of new floor space)
Essential	£1,740–£2,330 per m²	£73,000–£98,000
Standard	£1,890–£2,530 per m²	£79,000–£106,500
Premium	£2,260–£3,040 per m²	£95,000–£127,500

Planning and building regulations in Crumlin (Gwent)

In Wales, detached houses are more likely to meet the permitted development tests for a two-storey side extension: 10.5 m to the boundary opposite the side wall, a 1 m set-back from the front and no more than 50% added width. Rear permitted development allows 4 m on the ground floor and 3 m on the first floor. 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 Crumlin (Gwent) homes

Gaps to boundaries

Detached houses are often defined by the space around them. Keeping a gap to the side boundary at first floor maintains that character, helps planning and leaves access to the rear garden. In Wales the 10.5 m side distance decides whether permitted development applies.

Choosing the best side

On a detached house you can often extend on either side or the rear. We look at orientation for daylight, where the stairs and landing are, the distance to each boundary, drains and trees, so the extension goes where it adds the most useful space.

How we'd run your project

Measure and listen
A visit to Crumlin (Gwent) to understand how you live in the house now and what the extra rooms need to do, plus a first look at the structure.
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.
Price it properly
Once the engineer's calculations are in, we fix the build price in writing, with a clear list of what's included.
On site
One project lead runs the job, keeps you updated and arranges inspections at each stage until completion.

Questions about two-storey extensions for detached houses in Crumlin (Gwent)

How much does a two-storey extension for a detached house cost in Crumlin (Gwent)?

Our guide for Wales, which covers Crumlin (Gwent), is £1,890–£2,530 per m² including VAT. A typical project with a 3 m × 7 m footprint on two floors (42 m² of new floor space) comes to about £79,000–£106,500. Design and approval fees are extra, and we fix the build price in writing once the design is agreed.

Do I need planning permission for a two-storey extension for a detached house in Crumlin (Gwent)?

Crumlin (Gwent) is in Wales, so Wales planning rules apply. 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. If in doubt, a lawful development certificate or a planning application gives you certainty before you build.

Which postcodes do you cover around Crumlin (Gwent)?

We cover Crumlin (Gwent) (NP11) and nearby places including Newbridge, Abercarn and Blackwood, plus the rest of Gwent. The first site visit is free.

Is a detached house extension a better investment than moving?

It often costs less than the gap between your house and a larger one nearby, once property tax, legal fees and removal costs are counted, but that depends on your area. Extending also has limits: every street has a ceiling price. We give you build costs so you can compare them with local asking prices.

Can I extend a detached house on both sides?

Sometimes. With planning permission, a council may accept extensions on both sides if the house stays well proportioned and keeps gaps to the boundaries. It is more common to extend on one side and the rear, or with a wraparound. We look at the plot as a whole before suggesting more than one extension.

Nearby

Close to Crumlin (Gwent)? We work across the area, including:

Other extensions in Crumlin (Gwent)

All two-storey extension services in Crumlin (Gwent) · Two-storey extensions for detached houses across Gwent

Book a free site visit in Crumlin (Gwent) and we'll tell you what's possible, what approvals you need and what the design stage would cost.