Abergavenny · Gwent

Two-storey extensions for detached houses in Abergavenny

Thinking about a two-storey extension for a detached house in Abergavenny? We design it, take it through the approvals it needs and build it, with one team responsible from the first visit to the final certificate.

What we'd confirm first for a project in Abergavenny.

Postcode districts
NP7
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
Gilwern (3.3 miles), Blaenavon (4.4 miles), Brynmawr (7.2 miles)
Distance to Newport (Gwent)
about 16.1 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.

Around Abergavenny we also work in Gilwern, Blaenavon and Brynmawr, and across the rest of Gwent. Postcode district in and near Abergavenny: NP7.

What it costs in Abergavenny

In Wales, which includes Abergavenny, 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. Kitchens, bathroom fittings and flooring are priced separately so you can compare like with like.

SpecPer m²A 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 Abergavenny

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 Abergavenny homes

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.

Keeping it subordinate

Large detached houses can take a large extension, but councils still expect it to look secondary to the main house. A lower ridge, a modest set-back at the front and matching materials keep the proportions right, even on a wide plot.

How we'd run your project

  1. Free site visit

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

  2. Plans, then approval

    Measured survey, design, then the right approval route for your house. We explain each step before we take it.

  3. Engineer it

    Foundations sized for two floors, steels for any openings, and building control approval, all before anyone starts on site.

  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 detached houses in Abergavenny

Who handles building regulations for a project in Abergavenny?

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.

Which postcodes do you cover around Abergavenny?

We cover Abergavenny (NP7) and nearby places including Gilwern, Blaenavon and Brynmawr, plus the rest of Gwent. The first site visit is free.

How much does a two-storey extension for a detached house cost in Abergavenny?

Our guide for Wales, which covers Abergavenny, 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.

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

The same service in neighbouring towns:

Other extensions in Abergavenny

All two-storey extension services in Abergavenny · Two-storey extensions for detached houses across Gwent

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