Two-storey extensions for detached houses in Gosforth

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

Postcode districts: NE3, NE7, NE12 and NE13
County / area: Tyne and Wear, 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: Newcastle upon Tyne (1.8 miles), Gateshead (2.7 miles), Wallsend (3.3 miles)
Distance to Newcastle upon Tyne: about 1.8 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.

We cover Gosforth (NE3, NE7, NE12 and NE13) and the places around it, including Newcastle upon Tyne (1.8 miles), Gateshead (2.7 miles) and Wallsend.

What it costs in Gosforth

Guide prices for two-storey extensions for detached houses in North East England are around £1,840–£2,480 per m² of new floor space, including VAT. For a typical project with a 3 m × 7 m footprint on two floors (42 m² of new floor space), that's roughly £77,500–£104,000. Keep a contingency of around 10% for things nobody can see until the ground is opened up.

Spec	Per m²	A 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 Gosforth

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 Gosforth 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

Start at your house
We come to your home in Gosforth, measure up, check the ground floor walls and roof structure, and note anything near the boundaries.
Get it approved
Once you're happy with the design we submit it to the council for Gosforth and deal with any questions from the planning officer.
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 Gosforth

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 Gosforth?

We cover Gosforth (NE3, NE7, NE12 and NE13) and nearby places including Newcastle upon Tyne, Gateshead and Wallsend, plus the rest of Tyne and Wear. The first site visit is free.

Who handles building regulations for a project in Gosforth?

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.

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.

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

Nearby towns we cover for two-storey extensions for detached houses:

Other extensions in Gosforth

All two-storey extension services in Gosforth · Two-storey extensions for detached houses across Tyne and Wear

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