St Helier, Greater London
Terraced house rear extension in St Helier
Rear and side return extensions for terraces, with access through the house and two neighbours. If you live in St Helier and want to know what a terraced house rear extension would cost and whether it needs planning, start with the online guide price or a free site visit.
We cover St Helier (SM1, SM4 and SM5) as part of our Greater London work. Terraced streets make up much of the housing in parts of Greater London, and most rear extensions here go in without side access.
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 terraced house rear extension cost in St Helier?
A terraced house rear extension in St Helier is priced at £2,660–£4,290 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.
| Size | Guide price inc VAT |
|---|---|
| 3 m wide × 4.5 m deep (13.5 m²) | £36,000–£58,000 |
| 3 m wide × 6 m deep (18 m²) | £48,000–£77,000 |
These are guide ranges; the written quote after the survey is the figure that counts.
Do you need planning permission for a terraced house rear extension in St Helier?
The planning route for a terraced house rear extension in St Helier is set by England's householder rules and your council.
Under England's householder permitted development rules you can usually add 3 metres at the back of an attached house, or 4 metres on a detached house, without a planning application, as long as the extension stays under 4 metres high and its eaves stay under 3 metres where it is within 2 metres of a boundary.
Because rear extensions often sit on or near the boundary, the Party Wall etc. Act 1996 usually applies in England. Notices go out one or two months before work depending on the type of work, and a surveyor's award is only needed if a neighbour does not consent.
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 St Helier like to extend?
St Helier is mostly 1930s semis, short terraces and post-war houses, so full-width single-storey and two-storey rear extensions are realistic on many plots. Some later estates had permitted development rights removed by condition, so we check the planning history first.
How a terraced house rear extension in St Helier 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.
Design and guide price
Two or three layout options with a guide price for each, so you choose the design knowing what it costs.
Approvals
Permitted development check, prior approval or planning application, then Building Regulations drawings and structural calculations, plus party wall notices where they apply.
Fixed price and build
A written price for the agreed design, a start date and a named contact through the build, ending with the building control completion certificate.
Terraced house rear extensions near St Helier
From St Helier, the nearest places we also cover are Carshalton (1.2 miles) and Morden (1.3 miles).
- Terraced house rear extension in Carshalton
- Terraced house rear extension in Morden
- Terraced house rear extension in Mitcham
- Terraced house rear extension in Wallington
- Terraced house rear extension in Cheam
Other work in St Helier:
FAQ
Terraced house rear extension questions in St Helier
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.
Will I need a structural engineer?
Yes for the beam over the new opening and usually the foundations; we arrange them and their calculations go to building control.
Can a terrace have a two-storey rear extension?
It is possible but harder to get through planning because of the effect on both neighbours.
Who will build my extension?
Vetted building teams working under contract to us. Your contract is with S&K Property Investments and Improvement Ltd for the design and the build.
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.
Do I need a party wall agreement?
In England, usually yes if the extension is on or near a shared boundary or the foundations are close to a neighbour's building. We serve the notices.