Allerton · Merseyside

Kitchen extensions with bedrooms above in Allerton

Adding a kitchen extension with bedrooms above in Allerton gives you two new rooms stacked on one footprint. Here's how we'd approach it, what it typically costs and the rules that apply in England.

Quick reference for homeowners in Allerton.

Postcode districts
L19
County / area
Merseyside, England
Price region
North West England
Guide price
£53,000–£72,000 (£1,900–£2,560 per m²), kitchen units and worktops priced separately
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
Mossley Hill (1 mile), Woolton (1.1 miles), Hunts Cross (1.4 miles)
Distance to Liverpool
about 4.6 miles
First visit
Free, no obligation

About a kitchen extension with bedrooms above

A kitchen extension with bedrooms above is a two-storey extension designed so the ground floor becomes a larger, usually open-plan kitchen and dining space, with one or two bedrooms or a bathroom on the first floor. It is a natural fit for a two-storey rear extension. The key design issues are the steel beams that open up the house, glazing and ventilation.

We cover postcode district L19 in and around Allerton, along with neighbouring Mossley Hill, Woolton and Hunts Cross.

What it costs in Allerton

For budgeting in Allerton, allow around £53,000–£72,000 (kitchen units and worktops priced separately) for a kitchen extension with bedrooms above with a 4 m × 3.5 m footprint on two floors (28 m² of new floor space). That's based on £1,900–£2,560 per m² including VAT for North West England. We'll give you a written design-stage price first, then a fixed build price once the drawings are agreed.

SpecPer m²A 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 Allerton

In England, a two-storey rear kitchen extension can be permitted development if it goes no more than 3 m beyond the rear wall of the original house and stays at least 7 m from the rear boundary, with matching materials and roof pitch, outside protected areas. No balconies are allowed. Deeper designs need planning permission, costing £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 Allerton homes

Glazing and the Part L 25% rule

In England, new windows, roof lights and glazed doors in an extension are normally limited to 25% of the extension's floor area plus the area of any windows or doors removed. Larger glazing is possible, but needs SAP or compensating calculations, so we plan the rear doors around this from the start.

Steel beams and the open-plan opening

Removing the old rear wall to make one large room means a steel beam, sometimes several, to carry the first floor and roof. The engineer sizes the steel and its supports, and we decide early whether you want a flush ceiling with the beam hidden or a downstand, as this affects ceiling heights.

How we'd run your project

  1. Start at your house

    We come to your home in Allerton, 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. Fixed price in writing

    With approved drawings and calculations, we give you a fixed build price and a programme you can plan around.

  4. Build and sign-off

    Vetted teams working under S&K build the extension, and we arrange the building control completion certificate at the end.

Questions about kitchen extensions with bedrooms above in Allerton

Which postcodes do you cover around Allerton?

We cover Allerton (L19) and nearby places including Mossley Hill, Woolton and Hunts Cross, plus the rest of Merseyside. The first site visit is free.

How much does a kitchen extension with bedrooms above cost in Allerton?

Our guide for North West England, which covers Allerton, 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 (kitchen units and worktops priced separately). 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 Allerton?

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 it cheaper to build a kitchen extension and bedrooms at the same time?

Yes, in most cases. Building both floors at once means one set of foundations, one roof, one scaffold and one set of approvals. Adding a first floor later means removing the original roof, possibly strengthening the foundations and disrupting the kitchen again. If you think you will need the bedroom, build it now.

Can I keep using my kitchen during the build?

For part of it. The new structure can be built while your existing kitchen stays in use, but when the rear wall is opened and the new kitchen is fitted there will be several weeks without one. We plan when this happens and help you set up a temporary kitchen elsewhere in the house.

Nearby

The same service in neighbouring towns:

Other extensions in Allerton

All two-storey extension services in Allerton · Kitchen extensions with bedrooms above across Merseyside

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