St Leonards-on-Sea, East Sussex
Single-storey rear extension in St Leonards-on-Sea
Thinking about a single-storey rear extension in St Leonards-on-Sea? Ground-floor space across the back of the house, usually for a kitchen, dining or family room. Our team handles the drawings, the planning route and the build, and your contract is with one company throughout.
St Leonards-on-Sea sits in East Sussex, with postcode districts including TN34, TN37 and TN38. On inter-war semis and 1960s estates like those around St Leonards-on-Sea, a single-storey rear extension is usually the simplest way to fix a small back kitchen without touching the bedrooms.
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 single-storey rear extension cost in St Leonards-on-Sea?
In St Leonards-on-Sea, our guide for a single-storey rear extension is £2,130–£3,470 per square metre including VAT for a standard specification. South East prices run above our West Midlands baseline, mainly on labour rates and clay-soil foundations.
| Size | Guide price inc VAT |
|---|---|
| 3 m wide × 4 m deep (12 m²) | £25,500–£41,500 |
| 4 m wide × 5 m deep (20 m²) | £42,500–£69,500 |
| 4 m wide × 6 m deep (24 m²) | £51,000–£83,500 |
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 single-storey rear extension in St Leonards-on-Sea?
Here is how the rules in England apply to a single-storey rear extension in St Leonards-on-Sea.
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.
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 St Leonards-on-Sea like to extend?
Around St Leonards-on-Sea the housing ranges from inter-war semis to 1960s and 1970s estates with good-sized gardens. Many of the newer estates had permitted development rights removed by condition, so we check the planning history before anything is drawn.
How a single-storey rear extension in St Leonards-on-Sea 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.
Paperwork handled
Planning, prior approval or permitted development, Building Regulations approval, structural design and party wall notices are all handled by us.
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.
Single-storey rear extensions near St Leonards-on-Sea
From St Leonards-on-Sea, the nearest places we also cover are Hastings (1.5 miles) and Bexhill-on-Sea (3.3 miles).
- Single-storey rear extension in Hastings
- Single-storey rear extension in Bexhill-on-Sea
- Single-storey rear extension in Hailsham
- Single-storey rear extension in Eastbourne
- Single-storey rear extension in Seaford
Other work in St Leonards-on-Sea:
FAQ
Single-storey rear extension questions in St Leonards-on-Sea
How long does a rear extension take to build in St Leonards-on-Sea?
Most single-storey rear extensions take 10 to 16 weeks on site and two-storey extensions 16 to 26 weeks, after design and approvals.
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.
Is a flat roof or a pitched roof better?
A warm flat roof keeps the extension low under first-floor windows and suits a roof lantern; a pitched or lean-to roof gives a vaulted ceiling. Both last for decades when built properly.
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 you handle building control in St Leonards-on-Sea?
Yes. We apply to the council or a registered building control approver and hand over the completion certificate.
Can you match the brick or stone on my St Leonards-on-Sea house?
We source the closest match and show you samples before ordering; reclaimed materials are often the best match on older houses.