Hexham · Northumberland

Two-storey extensions for detached houses in Hexham

For a two-storey extension for a detached house in Hexham, the first questions are always the same: how big, which approvals, and what it will cost. This page answers all three for Northumberland.

Before you start in Hexham, here's what applies.

Postcode districts
NE45, NE46 and NE47
County / area
Northumberland, England
Price region
North East England
Guide price
£77,500–£104,000 (£1,840–£2,480 per m²)
Approval route
Depends on position: a two-storey rear extension may be permitted development (3 m deep, 7 m from the rear boundary); a two-storey side extension needs planning permission.
Nearest towns
Prudhoe (10 miles), Consett (13.5 miles), Haltwhistle (14 miles)
Distance to Blyth
about 25.9 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.

We cover postcode districts NE45, NE46 and NE47 in and around Hexham, along with neighbouring Prudhoe, Consett and Haltwhistle.

What it costs in Hexham

Our guide for North East England is £1,840–£2,480 per m² including VAT. On a project with a 3 m × 7 m footprint on two floors (42 m² of new floor space), that puts a two-storey extension for a detached house in Hexham at roughly £77,500–£104,000. We'll give you a written design-stage price first, then a fixed build price once the drawings are agreed.

SpecPer m²A 3 m × 7 m footprint on two floors (42 m² of new floor space)
Essential£1,700–£2,280 per m²£71,500–£95,500
Standard£1,840–£2,480 per m²£77,500–£104,000
Premium£2,210–£2,970 per m²£93,000–£124,500

Planning and building regulations in Hexham

In England, a two-storey rear extension on a detached house can be permitted development within 3 m of the original rear wall and at least 7 m from the rear boundary, with matching roof pitch and materials, outside protected areas. Any two-storey side or wraparound extension needs planning permission, costing £548 (or £575 for applications made from 8 December 2026), with a decision due within 8 weeks of validation.

Approval in England: Householder planning application: £548 (or £575 for applications made from 8 December 2026). Lawful development certificate: £274 (about £288 for applications from 8 December 2026). Councils should decide householder applications within 8 weeks of validation.

Building regulations: Building regulations approval (full plans recommended) from the council or a registered building control approver, with a completion certificate at the end.

Design points for Hexham homes

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.

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

  1. Start at your house

    We come to your home in Hexham, measure up, check the ground floor walls and roof structure, and note anything near the boundaries.

  2. Choose the approval route

    Some designs fit permitted development, most need a householder application. We decide which applies in England before drawing in detail.

  3. Detail and price

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

  4. Build and hand over

    We manage the build from groundworks to decoration-ready finish and hand over with the completion paperwork.

Questions about two-storey extensions for detached houses in Hexham

How long does a two-storey extension for a detached house take?

Allow 4 to 8 weeks for survey and design, then the approval period (councils should decide householder applications within 8 weeks of validation), 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 postcodes do you cover around Hexham?

We cover Hexham (NE45, NE46 and NE47) and nearby places including Prudhoe, Consett and Haltwhistle, plus the rest of Northumberland. The first site visit is free.

Who handles building regulations for a project in Hexham?

We handle it as part of the project. What's needed in England: building regulations approval (full plans recommended) from the council or a registered building control approver, with a completion certificate at the end. We prepare the drawings and the engineer's calculations, book the inspections and pass you the completion paperwork at the end.

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.

How big an extension can a detached house take?

It depends on the plot, the boundaries and local design policy rather than a fixed limit. Under permitted development in England, extensions must not cover more than 50% of the land around the original house. With planning permission, the council judges size on proportion, neighbours and the character of the area.

Nearby

We also cover places near Hexham, including:

Other extensions in Hexham

All two-storey extension services in Hexham · Two-storey extensions for detached houses across Northumberland

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

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