Swanley, Kent
Bungalow rear extension in Swanley
Bungalow rear extension in Swanley: single-storey rear extensions that keep everything on one level. We measure the house, show you what the rules allow, price it in writing and build it.
Swanley is covered from our Kent round, including BR8. For Swanley bungalows we design the roof first, because the low eaves decide the height of the new room.
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 Swanley?
In Swanley, our guide for a bungalow rear extension is £2,070–£3,360 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) | £25,000–£40,500 |
| 4 m wide × 6 m deep (24 m²) | £49,500–£80,500 |
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 bungalow rear extension in Swanley?
Planning for a bungalow rear extension in Swanley 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.
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 Swanley like to extend?
Around Swanley 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 bungalow rear extension in Swanley 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.
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.
Bungalow rear extensions near Swanley
We also build rear extensions for bungalows in nearby Bexley (3.2 miles) and Chelsfield (3.3 miles).
- Bungalow rear extension in Bexley
- Bungalow rear extension in Chelsfield
- Bungalow rear extension in Orpington
- Bungalow rear extension in Sidcup
- Bungalow rear extension in Dartford
Other work in Swanley:
FAQ
Bungalow rear extension questions in Swanley
Is the site visit in Swanley free?
Yes. We visit, measure up and talk through the options with no cost and no obligation.
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 bungalow extension cheaper?
The rates are similar per square metre; roof work can add a little.
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.
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.
Do you handle building control in Swanley?
Yes. We apply to the council or a registered building control approver and hand over the completion certificate.