Bungalow extensions across Swanley
If you live in Swanley and want more space without moving, a bungalow extension is one of the most practical ways to get it. We handle the drawings, approvals and the build.
- Guide price in SwanleyFrom £29,000 inc VAT
- PlanningSingle storey often permitted development
- Build time10–18 weeks on site
- Postcode districtsBR8

Planning and approvals in Swanley
In England a single-storey extension to a bungalow follows the normal permitted development limits (3 m or 4 m, or 6 m and 8 m through prior approval). Adding a first floor always needs planning permission.
In a conservation area, national park, National Landscape, the Broads or a World Heritage Site the permitted development limits are tighter (no side or two-storey extensions without an application). Listed homes need listed building consent, and if permitted development rights have been removed, any extension needs an application.
Building regulations approval is separate from planning. In England you can use the council's building control team or a registered building control approver; a full plans application gets the drawings checked before work starts, and the inspector signs the work off with a completion certificate.
If the work involves a shared wall, building on the boundary, or digging foundations within 3 m (sometimes 6 m) of a neighbour's building, the Party Wall etc. Act 1996 applies and notice must be served before work starts: two months for work to a party wall, one month for new walls on the boundary and for excavations.
Applications are decided by the local planning authority (your district, borough or unitary council).
Working in Swanley
Site visits are available across Swanley (BR8). Nearby, we also take on projects in Dartford (4 miles), Sevenoaks (9 miles), Gravesend (9 miles), Strood (13 miles).
In the South East, plenty of houses have already been extended once, which makes checking the remaining permitted development allowance an important early step.
What we take care of
- Level thresholds and accessible layouts
- Roof designs that tie into the existing hipped or gable roof
- Structural survey before any upward extension
- Single-storey extension options assessed first
- Planning application where needed
Bungalow extension prices in Swanley
Prices below are for Swanley, using the South East England factor of ×1.12. They are guide ranges including VAT for the build only, not a quote.
Typical rates in Swanley: £1,960 to £3,810 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 3 m × 5 m 15 m² | £29,000 – £35,500 | £34,000 – £45,000 | £43,500 – £57,500 |
| 4 m × 6 m 24 m² | £47,000 – £56,500 | £55,000 – £71,500 | £69,500 – £91,500 |
| L-shape 35 m² | £68,500 – £82,500 | £80,000 – £104,000 | £101,500 – £133,500 |
Want a range for your exact size? The guide-price tool takes about a minute.
Our process, step by step
Site visits are free and there is no obligation. Where drawings are needed, the design stage is priced in writing before it starts.
Free site visit
It starts with a visit to your house to measure, check access and talk through ideas and budget.
Design and approvals
Once the layout is agreed, we deal with the council: planning permission or written confirmation that none is needed, plus building control.
Fixed written price
With the design and specification agreed, you get a fixed written price and a start date.
Build and sign-off
We build it with one project manager, book the building control inspections and hand over the completion certificate.
Bungalow extension questions answered
Do I need building regulations approval in Swanley?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
Do you cover all of Swanley?
Yes. We cover Swanley and the surrounding parts of Kent. Site visits are free and there is no obligation.
How long does a bungalow extension take to build in Swanley?
On site, typically 10 to 18 weeks once approvals are in place. Before that, allow 6–14 weeks design and approvals.
Is it better to extend sideways or upwards?
Sideways and rearwards is usually simpler, cheaper and keeps single-level living. Upwards saves garden but means stairs, more structure and planning permission.
How much does a bungalow extension cost?
Our guide range for single-storey work is about £1,960 to £3,810 per m² including VAT. Going upwards is priced after a structural survey.
Book a free site visit in Swanley
We will measure up, check the planning position and give you honest guide figures.
- Free, no-obligation site visit
- Planning route checked before you spend on drawings
- Written price once the design is agreed
- Building control sign-off at the end
Prefer to talk? Call 0800 088 6341 or .
Book a free site visit
Tell us a little about the project and we will arrange a time.