Two-storey rear extensions in Liverpool

Quick reference for homeowners in Liverpool.

Postcode districts: L1, L2, L3, L69 and L70
County / area: Merseyside, England
Price region: North West England
Guide price: £53,000–£72,000 (£1,900–£2,560 per m²)
Approval route: It may be permitted development if it goes no more than 3 m beyond the original rear wall (counting any single-storey part) and stays 7 m from the rear boundary; otherwise it needs planning permission.
Nearest towns: Kensington (1 mile), Kirkdale (1.6 miles), Birkenhead (1.9 miles)
First visit: Free, no obligation

About a two-storey rear extension

A two-storey rear extension suits you if you need more room on both floors and have a reasonably deep garden. You get one team for the whole job: a measured survey, the design, a check on whether permitted development applies, planning drawings where they are needed, structural design, building regulations approval and the build itself, carried out by vetted teams working under S&K. Every project starts with a free site visit.

Around Liverpool we also work in Kensington, Kirkdale and Birkenhead, and across the rest of Merseyside. Postcode districts in and near Liverpool: L1, L2, L3, L69 and L70.

What it costs in Liverpool

Our guide for North West England is £1,900–£2,560 per m² including VAT. On a project with a 4 m × 3.5 m footprint on two floors (28 m² of new floor space), that puts a two-storey rear extension in Liverpool at roughly £53,000–£72,000. Keep a contingency of around 10% for things nobody can see until the ground is opened up.

Spec	Per m²	A 4 m × 3.5 m footprint on two floors (28 m² of new floor space)
Essential	£1,750–£2,360 per m²	£49,000–£66,000
Standard	£1,900–£2,560 per m²	£53,000–£72,000
Premium	£2,280–£3,080 per m²	£64,000–£86,000

Planning and building regulations in Liverpool

In England, a two-storey rear extension can be permitted development if it goes no more than 3 m beyond the rear wall of the original house, stays at least 7 m from the rear boundary and matches the house's materials and roof pitch. It is not permitted development in conservation areas, National Landscapes, National Parks, World Heritage Sites or the Broads. Otherwise a householder application costs £548 (or £575 for applications made from 8 December 2026).

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 Liverpool homes

Foundations and drains

Foundations for two storeys carry more load than a single storey and may need to go deeper near trees or on clay. Rear extensions often sit near drains, so we check sewer records early, as building over or near a public sewer may need the water company's agreement.

Opening up the ground floor

Knocking through the old rear wall means steel beams to carry the first floor and roof above. The structural engineer sets the beam sizes, padstones and any posts, and we plan them early so the open-plan layout you want is the one that gets built.

How we'd run your project

Look at the house
We start in Liverpool with a free visit: measurements, photos, a look at the loft and drains, and a frank chat about budget.
Drawings and permission
Our designers produce plans and elevations, then we take care of planning or permitted development checks with the council covering Liverpool.
Detail and price
Construction drawings, engineer's calculations and building control sign-off, then a written fixed price for the build.
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 rear extensions in Liverpool

How much does a two-storey rear extension cost in Liverpool?

Our guide for North West England, which covers Liverpool, is £1,900–£2,560 per m² including VAT. A typical project with a 4 m × 3.5 m footprint on two floors (28 m² of new floor space) comes to about £53,000–£72,000. Design and approval fees are extra, and we fix the build price in writing once the design is agreed.

Who handles building regulations for a project in Liverpool?

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.

Which postcodes do you cover around Liverpool?

We cover Liverpool (L1, L2, L3, L69 and L70) and nearby places including Kensington, Kirkdale and Birkenhead, plus the rest of Merseyside. The first site visit is free.

Will a two-storey rear extension block my neighbour's light?

It can if it is too deep or too close to the boundary, which is why councils look closely at its effect on neighbouring windows and gardens. We test the design against light and outlook early, keep the first floor shorter or set in where needed, and use a hipped roof to reduce bulk on the boundary side.

Can I have a balcony on a two-storey rear extension?

In England, balconies, verandas and raised platforms are not permitted development, so a balcony on a two-storey rear extension needs planning permission. A Juliet balcony, a guard rail across full-height doors with no platform to stand on, is often a practical alternative, but it still needs checking against the rules and the council's approach to overlooking.

Nearby

Nearby towns we cover for two-storey rear extensions:

Other extensions in Liverpool

All two-storey extension services in Liverpool · Two-storey rear extensions across Merseyside

Ready to talk it through? Call us or send the form and we'll arrange a visit to your home in Liverpool.