Greasby · Merseyside

Two-storey side extensions in Greasby

Thinking about a two-storey side extension in Greasby? We design it, take it through the approvals it needs and build it, with one team responsible from the first visit to the final certificate.

Quick reference for homeowners in Greasby.

Postcode districts
CH48 and CH49
County / area
Merseyside, England
Price region
North West England
Guide price
£82,000–£109,500 (£1,950–£2,610 per m²)
Approval route
Planning permission is needed: in England, permitted development only allows single-storey extensions to the side.
Nearest towns
Moreton (1.9 miles), Prenton (2.8 miles), Heswall (3.3 miles)
Distance to Liverpool
about 6.5 miles
First visit
Free, no obligation

About a two-storey side extension

A two-storey side extension suits a detached or semi-detached house with a side garden, driveway or garage wide enough to build on. You get a design that sits comfortably on the street, a planning application or permitted development check depending on your nation, structural design, building regulations approval and the build itself. We manage the whole process, and the work is carried out by vetted teams working under S&K.

Greasby sits about 6.5 miles from Liverpool. Closer to home, Moreton is 1.9 miles away and Prenton 2.8 miles.

What it costs in Greasby

Using our North West England rates, a two-storey side extension with a 3 m × 7 m footprint on two floors (42 m² of new floor space) comes to about £82,000–£109,500, including VAT. Bigger or more glazed designs cost more per m². Kitchens, bathroom fittings and flooring are priced separately so you can compare like with like.

SpecPer m²A 3 m × 7 m footprint on two floors (42 m² of new floor space)
Essential£1,790–£2,400 per m²£75,500–£101,000
Standard£1,950–£2,610 per m²£82,000–£109,500
Premium£2,340–£3,130 per m²£98,000–£131,500

Planning and building regulations in Greasby

In England, a two-storey side extension always needs householder planning permission, because permitted development only allows single-storey extensions beyond a side wall. The fee is £548 (or £575 for applications made from 8 December 2026), and councils should decide within 8 weeks of validation. Expect them to look at set-back, roof height, gaps to the boundary and the effect on neighbours.

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 Greasby homes

Side windows, boundaries and gutters

Upstairs windows in the side wall face the neighbour, so they are usually obscure-glazed and fixed, or left out. Building close to the boundary also raises questions about foundations, overhanging gutters and access for maintenance, so we design the eaves and gutter to stay within your land.

Avoiding a terracing effect

Where semi-detached houses sit close together, side extensions on neighbouring houses can join up and turn a row of pairs into a terrace. Many councils ask for a gap to the boundary at first floor to stop this, so we check local guidance before fixing the width.

How we'd run your project

  1. Look at the house

    We start in Greasby with a free visit: measurements, photos, a look at the loft and drains, and a frank chat about budget.

  2. Drawings and permission

    Our designers produce plans and elevations, then we take care of planning or permitted development checks with the council covering Greasby.

  3. Structure and building control

    A structural engineer sizes the foundations and steels, and we get building regulations approval before work starts.

  4. Finish and certify

    Second fix, plastering and making good, then building control's final inspection and the completion paperwork.

Questions about two-storey side extensions in Greasby

Who handles building regulations for a project in Greasby?

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.

How long does a two-storey side extension 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.

How much does a two-storey side extension cost in Greasby?

Our guide for North West England, which covers Greasby, is £1,950–£2,610 per m² including VAT. A typical project with a 3 m × 7 m footprint on two floors (42 m² of new floor space) comes to about £82,000–£109,500. Design and approval fees are extra, and we fix the build price in writing once the design is agreed.

Do I need planning permission for a two-storey side extension in Greasby?

Greasby is in England, so England planning rules apply. Planning permission is needed: in England, permitted development only allows single-storey extensions to the side. If in doubt, a lawful development certificate or a planning application gives you certainty before you build.

Can I build a two-storey side extension over my driveway?

Yes, if the drive is wide enough for a useful room and the council accepts the design. You may lose off-road parking, which some councils weigh up, and the foundations need to suit the ground below. We check parking, drains and meter positions at the free site visit before any drawings are prepared.

Nearby

We also cover places near Greasby, including:

Other extensions in Greasby

All two-storey extension services in Greasby · Two-storey side extensions across Merseyside

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

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