House extensions in Bexley
More space without moving: we plan and build extensions across Bexley, with one team for the drawings, the council and the build.
- Postcode districtsDA5, DA6, DA7, DA14, DA15, DA16
- Price regionLondon (×1.3)
- Planning rulesEngland
- Site visitFree, no obligation
Choosing the right extension in Bexley
London's housing is dominated by Victorian and Edwardian terraces, many with a rear outrigger and a side return, and 1930s semis in the outer boroughs. Conservation areas are common, so the planning check comes first.
Start by comparing wraparound extensions, kitchen extensions and glass box extensions: between them they cover most of the layouts we see requested for houses like these.
Where we work near Bexley
Postcode districts we cover around Bexley include DA5, DA6, DA7, DA14, DA15, DA16. Nearby, we also take on projects in Welling (2 miles), Abbey Wood (4 miles), Chislehurst (4 miles), Plumstead (4 miles), Eltham (4 miles). For homes towards Kent, Dartford is around 3 miles away.
What extensions cost in Bexley
Prices on this page use our London factor of ×1.3, include VAT at 20% and cover the build; your written price follows a survey and agreed drawings.
| Extension type | Example size | Standard spec (inc VAT) |
|---|---|---|
| Orangery extensions | 16 m² | £58,000 – £73,000 |
| Double-storey extensions | 32 m² | £74,500 – £98,000 |
| Side return extensions | 11 m² | £34,000 – £43,000 |
| Single-storey rear extensions | 20 m² | £53,000 – £68,000 |
| Kitchen extensions | 20 m² | £54,500 – £69,000 |
Planning rules in Bexley
In England a single-storey rear extension can usually go up to 3 m beyond the original rear wall of a semi-detached or terraced house, or 4 m on a detached house, without a planning application, provided it is no more than 4 m high, keeps eaves to 3 m within 2 m of a boundary and, with other buildings, covers no more than half the land around the original house. The larger home extension prior approval scheme raises those depths to 6 m and 8 m, with neighbours notified and a 42-day decision.
In England a two-storey rear extension is permitted development only if it projects no more than 3 m from the original rear wall, sits at least 7 m from the rear boundary, matches the roof pitch and uses obscure, non-opening side windows upstairs. Most two-storey extensions therefore go through a householder planning application, which costs £548 from 1 April 2026 and normally takes about 8 weeks.
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.
Applications are decided by the local planning authority (your district, borough or unitary council).
Extension types and starting prices
- Glass box extensions · from £39,000
- Building regulations for extensions · from £1,150
- Porch extensions · from £5,200
- Timber frame extensions · from £27,000
- Side return extensions · from £23,000
- Bungalow extensions · from £34,000
- Planning permission for extensions · from £450
- Kitchen extensions · from £35,000
- Conservatory replacement extensions · from £26,000
- Utility and boot room extensions · from £18,000
- Orangery extensions · from £39,000
- Extensions over a garage · from £31,000
- Side extensions · from £28,500
- Flat roof extensions · from £27,000
- Home office extensions · from £20,500
- Wraparound extensions · from £46,500
- Annexe extensions · from £71,500
- Bedroom extensions · from £33,500
- Pitched roof extensions · from £28,500
- Double-storey extensions · from £49,000
- Extension plans and drawings · from £1,550
- Single-storey rear extensions · from £27,000
Free site visit
It starts with a visit to your house to measure, check access and talk through ideas and budget.
Design and approvals
We produce the drawings and structural design, and manage the approvals so they are in place before work starts.
Fixed written price
With the design and specification agreed, you get a fixed written price and a start date.
Build and sign-off
The build is managed from start to finish, inspected at each stage and signed off on completion.
Questions about extensions in Bexley
How much does an extension cost in Bexley?
Using our London factor (×1.3), a standard-spec single-storey extension of 20 m² is a guide £53,000 to £68,000 including VAT, and a 32 m² two-storey extension £74,500 to £98,000. Your written price follows the survey.
Do I need planning permission for an extension in Bexley?
Not always. It depends on the size, position and your property's history. Many single-storey rear extensions in England are permitted development or can use prior approval.
Who do I contract with?
Your contract is with S&K Property Investments and Improvement Ltd, which designs and manages the project and the build teams who carry it out.
Do you handle building regulations?
Yes. We prepare the drawings and calculations, submit them and book inspections, ending with a completion certificate.
Do you cover all of Bexley?
Yes, including the surrounding parts of Greater London. Site visits are free and there is no obligation.
Book a free site visit in Bexley
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.