Two-storey extensions for semi-detached houses in Newcastle upon Tyne

Before you start in Newcastle upon Tyne, here's what applies.

Postcode districts: NE1, NE2, NE4 and NE99
County / area: Tyne and Wear, England
Price region: North East England
Guide price: £50,500–£68,000 (£1,800–£2,430 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: Gateshead (0.9 miles), Gosforth (1.8 miles), Felling (2.2 miles)
First visit: Free, no obligation

About a two-storey extension for a semi-detached house

A two-storey extension for a semi-detached house is a two-floor addition to the rear, the open side, or both, designed around the attached neighbour on one side. The rear is often the simplest option and can sometimes be permitted development, while a side extension uses the gap on the detached side. Both need care with the shared party wall and the neighbour's light.

Around Newcastle upon Tyne we also work in Gateshead, Gosforth and Felling, and across the rest of Tyne and Wear. Postcode districts in and near Newcastle upon Tyne: NE1, NE2, NE4 and NE99.

What it costs in Newcastle upon Tyne

Expect a two-storey extension for a semi-detached house in Newcastle upon Tyne to land somewhere around £50,500–£68,000 for a 4 m × 3.5 m footprint on two floors (28 m² of new floor space). Our North East England guide rate is £1,800–£2,430 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 4 m × 3.5 m footprint on two floors (28 m² of new floor space)
Essential	£1,660–£2,240 per m²	£46,500–£62,500
Standard	£1,800–£2,430 per m²	£50,500–£68,000
Premium	£2,160–£2,920 per m²	£60,500–£81,500

Planning and building regulations in Newcastle upon Tyne

In England, a two-storey rear extension on a semi can be permitted development if it goes no more than 3 m beyond the original rear wall and stays 7 m from the rear boundary, with matching materials and roof pitch. A two-storey side or wraparound extension always needs planning permission, costing £548 (or £575 for applications made from 8 December 2026). Protected areas such as conservation areas exclude two-storey rear permitted development.

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 Newcastle upon Tyne homes

The attached neighbour's light

A two-storey rear extension next to the party wall can take light from the neighbour's rear windows. Councils often use a 45-degree test, so the first floor may need to be shorter than the ground floor or set in from the shared boundary.

Rear, side or both

On a semi, a rear extension sits against the attached neighbour, while a side extension faces the detached neighbour and the street. We compare the space, cost and approval route for each, and for a wraparound, before you commit to one design.

How we'd run your project

Look at the house
We start in Newcastle upon Tyne with a free visit: measurements, photos, a look at the loft and drains, and a frank chat about budget.
Plans, then approval
Measured survey, design, then the right approval route for your house. We explain each step before we take it.
Structure and building control
A structural engineer sizes the foundations and steels, and we get building regulations approval before work starts.
Build
Foundations, walls, floor, roof, windows, then first and second fix. We break through into the house as late as we can.

Questions about two-storey extensions for semi-detached houses in Newcastle upon Tyne

How long does a two-storey extension for a semi-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 Newcastle upon Tyne?

We cover Newcastle upon Tyne (NE1, NE2, NE4 and NE99) and nearby places including Gateshead, Gosforth and Felling, plus the rest of Tyne and Wear. The first site visit is free.

Do I need planning permission for a two-storey extension for a semi-detached house in Newcastle upon Tyne?

Newcastle upon Tyne is in England, so England planning rules apply. 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. If in doubt, a lawful development certificate or a planning application gives you certainty before you build.

Should I extend my semi to the side or the rear?

It depends on your plot and what you need. A rear extension keeps the side drive and can sometimes be permitted development, but it affects the attached neighbour. A side extension keeps the rear garden but always needs planning permission in England. We compare both at the free site visit.

What if my neighbour has already extended?

That often helps. An existing extension next door can reduce the effect of yours on their light, and may show what the council accepts on your street. It can also mean building alongside their wall, so we check its position, foundations and any windows facing your plot at the survey.

Nearby

We also cover places near Newcastle upon Tyne, including:

Other extensions in Newcastle upon Tyne

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

Send us your postcode and a few details. We'll get back to you to arrange a visit and talk through your options.