Goodmayes · Greater London

Two-storey side extensions in Goodmayes

If you live in Goodmayes and need more room without moving, a two-storey side extension is worth a serious look. We handle the drawings, approvals, structure and build.

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

Postcode districts
IG3
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
Becontree (1 mile), Chadwell Heath (1.1 miles), Ilford (1.7 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.

Around Goodmayes we also work in Becontree, Chadwell Heath and Ilford, and across the rest of Greater London. Postcode district in and near Goodmayes: IG3.

What it costs in Goodmayes

Most of the cost of a two-storey side extension is set by its size and specification. For Goodmayes 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). Professional fees for drawings and the structural engineer are listed separately on our prices page.

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 Goodmayes

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 Goodmayes homes

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.

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. Free site visit

    We visit your home in Goodmayes, look at the structure, access and boundaries, and talk through what you want the new rooms to do.

  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. Structure and building control

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

  4. 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 side extensions in Goodmayes

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.

Which postcodes do you cover around Goodmayes?

We cover Goodmayes (IG3) and nearby places including Becontree, Chadwell Heath and Ilford, plus the rest of Greater London. The first site visit is free.

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

Our guide for London, which covers Goodmayes, 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 Goodmayes?

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

The same service in neighbouring towns:

Other extensions in Goodmayes

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

The quickest next step is a visit. We'll look at your house in Goodmayes and give you an honest view of the options.

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