Wimbledon, Greater London
Semi-detached rear extension in Wimbledon
Semi-detached rear extension in Wimbledon: single or two-storey extensions for semi-detached houses, with side access and one party wall. We measure the house, show you what the rules allow, price it in writing and build it.
Wimbledon and its postcode districts SW17, SW19 and SW20 are part of our Greater London coverage. Where a Wimbledon 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 Wimbledon?
Guide prices for a semi-detached rear extension in Wimbledon start from our London rate of £2,470–£4,030 per square metre, including VAT. London prices sit at the top of our range because of labour rates, access through the house, parking suspensions and skip licences.
| Size | Guide 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 |
Your written price follows a measured survey and an agreed design, so it reflects your house, not an average.
Do you need planning permission for a semi-detached rear extension in Wimbledon?
Planning for a semi-detached rear extension in Wimbledon follows the English householder rules.
In England a single-storey rear extension can often be built under permitted development: up to 3 metres beyond the original rear wall of an attached house, or 4 metres on a detached house, no higher than 4 metres, with eaves no higher than 3 metres if any part is 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. We check your house's planning history and any conservation area before drawing, so the route is clear before you spend on plans.
What are homes in Wimbledon like to extend?
Period terraces in Wimbledon sit alongside flats, and the difference matters: houses usually keep permitted development rights, while flats and maisonettes need planning permission for any rear extension.
How a semi-detached rear extension in Wimbledon comes together
Survey visit
We visit free of charge, measure up, check access, drainage and neighbours' extensions, and note what you want the room to do.
Options and costs
We draw layout options and price each one, so the budget shapes the design rather than surprising you later.
Planning and regulations
We take the design through the right planning route, then produce the construction drawings and engineer's calculations for building control.
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 Wimbledon
From Wimbledon, the nearest places we also cover are Wimbledon Park (1.0 miles) and Morden (1.7 miles).
- Semi-detached rear extension in Wimbledon Park
- Semi-detached rear extension in Morden
- Semi-detached rear extension in Earlsfield
- Semi-detached rear extension in Tooting
- Semi-detached rear extension in Mitcham
Other work in Wimbledon:
FAQ
Semi-detached rear extension questions in Wimbledon
What postcode areas do you cover around Wimbledon?
Including SW17, SW19 and SW20, and the surrounding Greater London area.
How long does a rear extension take to build in Wimbledon?
Most single-storey rear extensions take 10 to 16 weeks on site and two-storey extensions 16 to 26 weeks, after design and approvals.
Do I need a party wall agreement?
Usually with the attached neighbour, in England and Wales.
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 Wimbledon free?
Yes. We visit, measure up and talk through the options with no cost and no obligation.
Do you handle building control in Wimbledon?
Yes. We apply to the council or a registered building control approver and hand over the completion certificate.