Edmonton · Greater London

Two-storey side extensions in Edmonton

Want to stay in Edmonton but need more space? A two-storey side extension adds floor area on two levels without giving up much garden. Here's what's involved.

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

Postcode districts
N9
County / area
Greater London, England
Price region
London
Guide price
£103,500–£138,500 (£2,460–£3,300 per m²)
Approval route
Planning permission is needed: in England, permitted development only allows single-storey extensions to the side.
Nearest towns
Ponders End (1.4 miles), Tottenham (1.6 miles), Southgate (1.9 miles)
First visit
Free, no obligation

About a two-storey side extension

A two-storey side extension is a new two-floor addition built into the space beside your house, often over a driveway or side passage. It typically adds one or two bedrooms upstairs and a utility, study or larger kitchen below, without giving up rear garden.

We cover Edmonton (N9) and the places around it, including Ponders End (1.4 miles), Tottenham (1.6 miles) and Southgate.

What it costs in Edmonton

Most of the cost of a two-storey side extension is set by its size and specification. For Edmonton and the rest of London, our guide is £2,460–£3,300 per m² including VAT, so about £103,500–£138,500 for a 3 m × 7 m footprint on two floors (42 m² of new floor space). Keep a contingency of around 10% for things nobody can see until the ground is opened up.

SpecPer m²A 3 m × 7 m footprint on two floors (42 m² of new floor space)
Essential£2,260–£3,040 per m²£95,000–£127,500
Standard£2,460–£3,300 per m²£103,500–£138,500
Premium£2,950–£3,960 per m²£124,000–£166,500

Planning and building regulations in Edmonton

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 Edmonton homes

Access and services

Side extensions often cover the only route to the back garden, a gas meter, soil pipes or a drain run. We plan bin and bike access, move meters and pipes where needed and check drains early, because these items affect both cost and layout.

Set-down and set-back

Councils usually want a two-storey side extension to look subordinate to the house. Setting the front wall back from the main front and dropping the ridge slightly below the main roof helps it read as an addition, and is often expected in local design guidance.

How we'd run your project

  1. Understand the brief

    At your home in Edmonton we agree what you need: bedroom count, bathroom, kitchen space, and how much garden you want to keep.

  2. Drawings, then consent

    We draw the scheme, check it against the rules in England, and take it through the right consent with the council.

  3. Engineer it

    Foundations sized for two floors, steels for any openings, and building control approval, all before anyone starts on site.

  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 two-storey side extensions in Edmonton

Which postcodes do you cover around Edmonton?

We cover Edmonton (N9) and nearby places including Ponders End, Tottenham and Southgate, plus the rest of Greater London. The first site visit is free.

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 Edmonton?

Our guide for London, which covers Edmonton, is £2,460–£3,300 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 £103,500–£138,500. 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 Edmonton?

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 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

Close to Edmonton? We work across the area, including:

Other extensions in Edmonton

All two-storey extension services in Edmonton · Two-storey side extensions across Greater London

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

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