Rotherhithe · Greater London

Two-storey side extensions in Rotherhithe

Thinking about a two-storey side extension in Rotherhithe? 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.

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

Postcode districts
SE16
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
Shadwell (0.8 miles), Whitechapel (1.2 miles), Limehouse (1.2 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.

Around Rotherhithe we also work in Shadwell, Whitechapel and Limehouse, and across the rest of Greater London. Postcode district in and near Rotherhithe: SE16.

What it costs in Rotherhithe

A guide price for Rotherhithe: 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%. 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£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 Rotherhithe

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 Rotherhithe 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. Free site visit

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

  2. Design and approvals

    We draw the extension and check it against the rules for England, then apply for planning permission or a certificate of lawfulness, whichever fits.

  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 Rotherhithe

Who handles building regulations for a project in Rotherhithe?

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.

Which postcodes do you cover around Rotherhithe?

We cover Rotherhithe (SE16) and nearby places including Shadwell, Whitechapel and Limehouse, plus the rest of Greater London. The first site visit is free.

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

Our guide for London, which covers Rotherhithe, 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.

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

Other towns near Rotherhithe:

Other extensions in Rotherhithe

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

Send us your postcode and a few details. We'll get back to you to arrange a visit and talk through your options.

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