House extensions in Banbury
More space without moving: we plan and build extensions across Banbury, with one team for the drawings, the council and the build.
- Postcode districtsOX16
- Price regionSouth East England (×1.12)
- Planning rulesEngland
- Site visitFree, no obligation
Choosing the right extension in Banbury
The South East has a broad mix of 1930s semis, post-war estates, newer developments and period cottages, and many houses have enough garden for a generous rear extension.
Start by comparing double-storey extensions, single-storey rear extensions and wraparound extensions: between them they cover most of the layouts we see requested for houses like these.
Planning rules in Banbury
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).
Banbury extension prices at a glance
We publish guide prices so you can budget before anyone visits. For Banbury they are adjusted by ×1.12, the factor we use across South East England.
| Extension type | Example size | Standard spec (inc VAT) |
|---|---|---|
| Single-storey rear extensions | 20 m² | £45,500 – £58,500 |
| Double-storey extensions | 32 m² | £64,500 – £84,500 |
| Side return extensions | 11 m² | £29,500 – £37,000 |
| Orangery extensions | 16 m² | £50,000 – £63,000 |
| Extensions over a garage | 12 m² | £28,000 – £36,500 |
| Conservatory replacement extensions | 14 m² | £33,500 – £43,500 |
Covering Banbury and nearby
Site visits are available across Banbury (OX16). We also work in nearby Bicester (14 miles), Witney (20 miles), Oxford (22 miles), Carterton (23 miles), Abingdon (27 miles). Brackley, in Northamptonshire, is roughly 9 miles from Banbury and also on our list.
All extension types we build in Banbury
- Extensions over a garage · from £26,500
- Annexe extensions · from £61,500
- Double-storey extensions · from £42,500
- Conservatory replacement extensions · from £22,000
- Single-storey rear extensions · from £23,500
- Wraparound extensions · from £40,000
- Kitchen extensions · from £30,000
- Glass box extensions · from £33,500
- Home office extensions · from £17,500
- Side extensions · from £24,500
- Orangery extensions · from £33,500
- Building regulations for extensions · from £1,000
- Porch extensions · from £4,450
- Bungalow extensions · from £29,000
- Pitched roof extensions · from £24,500
- Flat roof extensions · from £23,500
- Side return extensions · from £20,000
- Planning permission for extensions · from £350
- Utility and boot room extensions · from £15,500
- Timber frame extensions · from £23,500
- Bedroom extensions · from £29,000
- Extension plans and drawings · from £1,300
Free site visit
A designer visits, takes measurements and photos, and discusses layouts, budget and timing with you.
Design and approvals
We draw the design, agree it with you and handle planning or permitted development checks and building regulations.
Fixed written price
The price is fixed in writing once the design is settled, with a clear programme and payment stages.
Build and sign-off
Work is carried out to the agreed programme, inspected by building control and signed off at the end.
Questions about extensions in Banbury
How much does an extension cost in Banbury?
Using our South East England factor (×1.12), a standard-spec single-storey extension of 20 m² is a guide £45,500 to £58,500 including VAT, and a 32 m² two-storey extension £64,500 to £84,500. Your written price follows the survey.
Do you cover all of Banbury?
Yes, including the surrounding parts of Oxfordshire. Site visits are free and there is no obligation.
Will my neighbours need to be told?
If you apply for planning or prior approval the council notifies them, and in England party wall notices may be needed for work near a shared boundary.
Do I need planning permission for an extension in Banbury?
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.
Book a free site visit in Banbury
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.