Rear extension design, approvals and build across the UKCall 0800 088 6341 · Online guide price
Rear Extensionsrear-extensions.co.uk 0800 088 6341 Get a guide price

Rotherhithe, Greater London

Semi-detached rear extension in Rotherhithe

Thinking about a semi-detached rear extension in Rotherhithe? Single or two-storey extensions for semi-detached houses, with side access and one party wall. Our team handles the drawings, the planning route and the build, and your contract is with one company throughout.

Rotherhithe sits in Greater London, with postcode districts including E1, E1W and SE16. Where a Rotherhithe semi already has a small lean-to at the back, we usually replace it rather than extend it.

Book a free site visit

Tell us about the house and we'll call to arrange a free, no-obligation visit.

How much does a semi-detached rear extension cost in Rotherhithe?

A semi-detached rear extension in Rotherhithe is priced at £2,470–£4,030 per square metre including VAT as a guide, before kitchen fit-out and fees. London prices sit at the top of our range because of labour rates, access through the house, parking suspensions and skip licences.

Semi-detached rear extension prices in Rotherhithe
SizeGuide price inc VAT
3 m wide × 4 m deep (12 m²)£29,500–£48,500
4 m wide × 5 m deep (20 m²)£49,500–£80,500
4 m wide × 6 m deep (24 m²)£59,500–£96,500

These are guide ranges; the written quote after the survey is the figure that counts.

Do you need planning permission for a semi-detached rear extension in Rotherhithe?

Planning for a semi-detached rear extension in Rotherhithe follows the English householder rules.

English permitted development (Class A) allows a single-storey rear extension of 3 metres on a terraced or semi-detached house and 4 metres on a detached one, measured from the original house, with a maximum height of 4 metres and eaves of no more than 3 metres within 2 metres of a boundary.

A two-storey rear extension can be permitted development in England only if it projects no more than 3 metres, stays at least 7 metres from the rear boundary, matches the existing roof pitch and has obscure-glazed upper side windows. In practice most double-storey rear extensions go through a householder planning application.

England also has the larger home extension route: a single-storey rear extension of up to 6 metres on an attached house or 8 metres on a detached house, after prior approval from the council. The council notifies your neighbours and has 42 days to decide; the fee is £249 (£310 for applications made from 8 December 2026). The route is not available on designated land such as conservation areas.

Conservation areas, National Parks, National Landscapes and the Broads restrict permitted development, and listed buildings always need listed building consent. At the first visit we measure what is there now and tell you which route fits: permitted development, prior approval or a planning application.

What are homes in Rotherhithe like to extend?

Much of Rotherhithe is Victorian and Edwardian terraced housing with narrow back additions, which suits side returns, wraparounds and 3 metre rear extensions. Many streets are in conservation areas, gardens are short, and almost everything comes through the house or along a rear alley.

How a semi-detached rear extension in Rotherhithe comes together

  1. Look round and measure

    A free visit to see the back of the house, measure it, check the drains and boundaries and hear what you need.

  2. Options and costs

    We draw layout options and price each one, so the budget shapes the design rather than surprising you later.

  3. Paperwork handled

    Planning, prior approval or permitted development, Building Regulations approval, structural design and party wall notices are all handled by us.

  4. Written price, then build

    Once the design and approvals are in place, you get a fixed written price and programme, and we build through to sign-off.

Semi-detached rear extensions near Rotherhithe

From Rotherhithe, the nearest places we also cover are Whitechapel (1.2 miles) and Limehouse (1.2 miles).

Other work in Rotherhithe:

All rear extensions in Rotherhithe

FAQ

Semi-detached rear extension questions in Rotherhithe

Can I get a price without a visit?

Our online guide-price tool gives a range in a couple of minutes. A written price needs a survey.

Do I need planning permission for a rear extension in Rotherhithe?

Often not for a single-storey rear extension of up to 3 metres (4 metres on a detached house) under permitted development, or up to 6 or 8 metres with prior approval, unless the house is in a conservation area or its rights have been removed.

How far can I extend a semi without planning?

3 metres under permitted development in England, or up to 6 metres with prior approval, outside designated land.

Can you match the brick or stone on my Rotherhithe house?

We source the closest match and show you samples before ordering; reclaimed materials are often the best match on older houses.

Can I live at home while the extension is built?

Usually yes. Most of the work is outside until the back wall is opened near the end, and that stage is screened off.

Is the site visit in Rotherhithe free?

Yes. We visit, measure up and talk through the options with no cost and no obligation.

Next step

See what your rear extension would cost

Get a guide price online in a couple of minutes, or book a free site visit and we'll measure up and talk you through the planning route.

CallGuide price