St Helier, Greater London
Bungalow rear extension in St Helier
We plan and build rear extensions for bungalows for homeowners in St Helier. Single-storey rear extensions that keep everything on one level. Start with a free site visit, then a written price once the design is agreed.
St Helier and its postcode districts SM1, SM4 and SM5 are part of our Greater London coverage. For bungalows in Greater London, a rear extension is the usual way to add space without adding stairs.
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 bungalow rear extension cost in St Helier?
A bungalow rear extension in St Helier is priced at £2,400–£3,900 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 m deep (12 m²) | £29,000–£47,000 |
| 4 m wide × 6 m deep (24 m²) | £57,500–£93,500 |
We put a fixed price in writing once the design is agreed, and explain any provisional sums such as foundations.
Do you need planning permission for a bungalow rear extension in St Helier?
Whether your bungalow rear extension in St Helier needs a planning application depends on its size, your house and any local restrictions.
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.
If 3 or 4 metres is not enough, England's prior approval route allows 6 metres on a terraced or semi-detached house and 8 metres on a detached house for a single-storey rear extension. Neighbours are consulted, the council decides within 42 days, and the fee is £249, rising to £310 from 8 December 2026.
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?
Much of St Helier is 1920s and 1930s semis and short terraces with longer gardens than inner London, which suit full-width single-storey rear extensions. Parking suspensions, skip licences and controlled hours on residential streets shape the programme more than the build itself.
How a bungalow rear extension in St Helier comes together
Free site visit
We measure the house and garden, look at the back wall, drainage and boundaries, and talk through what you want from the space.
Design and guide price
Two or three layout options with a guide price for each, so you choose the design knowing what it costs.
Planning and regulations
We take the design through the right planning route, then produce the construction drawings and engineer's calculations for building control.
Build and sign-off
We build to the approved drawings with regular updates, then hand over the building control completion certificate and any guarantees from suppliers.
Bungalow rear extensions near St Helier
Neighbouring places we cover include Carshalton (1.2 miles) and Morden (1.3 miles).
- Bungalow rear extension in Carshalton
- Bungalow rear extension in Morden
- Bungalow rear extension in Mitcham
- Bungalow rear extension in Wallington
- Bungalow rear extension in Cheam
Other work in St Helier:
FAQ
Bungalow rear extension questions in St Helier
What postcode areas do you cover around St Helier?
Including SM1, SM4 and SM5, and the surrounding Greater London area.
How much does a bungalow rear extension cost in St Helier?
As a guide, £2,400–£3,900 per square metre including VAT for a standard specification. For example, 3 m wide × 4 m deep (12 m²): about £29,000–£47,000 at that rate. Your written price follows the survey.
Will the roof look odd?
Not if the pitch and tiles match. Where the eaves are low, a flat-roofed section with a lantern is an alternative.
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.
Can you match the brick or stone on my St Helier house?
We source the closest match and show you samples before ordering; reclaimed materials are often the best match on older houses.
How long does a rear extension take to build in St Helier?
Most single-storey rear extensions take 10 to 16 weeks on site and two-storey extensions 16 to 26 weeks, after design and approvals.