Hackney · Greater London

Two-storey side extensions in Hackney

Want to stay in Hackney 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.

What we'd confirm first for a project in Hackney.

Postcode districts
E5, E8 and E9
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
Bethnal Green (1.3 miles), Canonbury (1.5 miles), Stamford Hill (1.8 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.

We cover postcode districts E5, E8 and E9 in and around Hackney, along with neighbouring Bethnal Green, Canonbury and Stamford Hill.

What it costs in Hackney

A guide price for Hackney: around £103,500–£138,500 for a 3 m × 7 m footprint on two floors (42 m² of new floor space). That works out at £2,460–£3,300 per m² of new floor space, including VAT at 20%. We'll give you a written design-stage price first, then a fixed build price once the drawings are agreed.

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 Hackney

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 Hackney 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. Visit and first ideas

    One of our team visits your house in Hackney, checks the walls, roof and drains, and sketches out options with you.

  2. Plans, then approval

    Measured survey, design, then the right approval route for your house. We explain each step before we take it.

  3. Technical design

    We prepare the building regulations drawings, structural calculations and specification so the build price can be fixed.

  4. Build it

    The new structure goes up first, then we open into the house, finish inside and get the completion certificate.

Questions about two-storey side extensions in Hackney

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

Our guide for London, which covers Hackney, 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.

Which postcodes do you cover around Hackney?

We cover Hackney (E5, E8 and E9) and nearby places including Bethnal Green, Canonbury and Stamford Hill, plus the rest of Greater London. The first site visit is free.

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

Hackney 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.

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.

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 Hackney? We work across the area, including:

Other extensions in Hackney

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

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

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