Brecon · Powys

Two-storey extensions for detached houses in Brecon

Want to stay in Brecon but need more space? A two-storey extension for a detached house adds floor area on two levels without giving up much garden. Here's what's involved.

Useful details for planning a two-storey extension for a detached house in Brecon.

Postcode districts
LD3
County / area
Powys, 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
Brynmawr (13.4 miles), Tredegar (13.4 miles), Rhymney (13.6 miles)
Distance to Newtown
about 39.6 miles
First visit
Free, no obligation

About a two-storey extension for a detached house

A two-storey extension for a detached house is a two-floor addition to the side, rear or both of a house that stands on its own plot. Detached houses often have room on more than one side, so there is more choice of layout and fewer shared-wall issues. The design still needs to respect boundaries, neighbours' windows and the look of the house.

Brecon sits about 39.6 miles from Newtown. Closer to home, Brynmawr is 13.4 miles away and Tredegar 13.4 miles.

What it costs in Brecon

A guide price for Brecon: around £79,000–£106,500 for a 3 m × 7 m footprint on two floors (42 m² of new floor space). That works out at £1,890–£2,530 per m² of new floor space, including VAT at 20%. Professional fees for drawings and the structural engineer are listed separately on our prices page.

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 Brecon

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 Brecon homes

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.

Larger spans and steelwork

Bigger extensions often mean wider openings and longer spans, which need more steel and sometimes a steel frame. The engineer designs these early, because the size of the steel affects ceiling heights, floor depths and the cost.

How we'd run your project

  1. Understand the brief

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

  2. Drawings, then consent

    We draw the scheme, check it against the rules in Wales, and take it through the right consent with the council.

  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. 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 Brecon

Who handles building regulations for a project in Brecon?

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

Our guide for Wales, which covers Brecon, 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 Brecon?

Brecon 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.

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

Other towns near Brecon:

Other extensions in Brecon

All two-storey extension services in Brecon · Two-storey extensions for detached houses across Powys

Tell us about your house in Brecon and we'll call you back to arrange a free, no-obligation visit.

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