House extensions in Brackley
Planning an extension in Brackley? Compare extension types, see guide prices adjusted for Brackley and book a free site visit.
- Postcode districtsNN13
- Price regionEast Midlands (×0.95)
- Planning rulesEngland
- Site visitFree, no obligation
What extensions cost in Brackley
We publish guide prices so you can budget before anyone visits. For Brackley they are adjusted by ×0.95, the factor we use across East Midlands.
| Extension type | Example size | Standard spec (inc VAT) |
|---|---|---|
| Extensions over a garage | 12 m² | £23,500 – £31,000 |
| Orangery extensions | 16 m² | £42,500 – £53,500 |
| Conservatory replacement extensions | 14 m² | £28,500 – £37,000 |
| Wraparound extensions | 25 m² | £54,500 – £69,000 |
| Double-storey extensions | 32 m² | £54,500 – £71,500 |
Where we work near Brackley
Our survey diary covers Brackley, including NN13. We also work in nearby Towcester (9 miles), Daventry (16 miles), Northampton (19 miles), Wellingborough (27 miles), Rushden (29 miles). For homes towards Oxfordshire, Banbury is around 9 miles away.
Planning rules in Brackley
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.
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).
Choosing the right extension in Brackley
The East Midlands has plenty of inter-war and post-war semis and detached houses with room to extend, alongside Victorian terraces in the towns.
The types we would usually look at first for a home in Brackley are double-storey extensions, conservatory replacement extensions and single-storey rear extensions, depending on the garden and how the house is laid out.
All extension types we build in Brackley
- Extension plans and drawings · from £1,100
- Wraparound extensions · from £34,000
- Single-storey rear extensions · from £19,500
- Home office extensions · from £15,000
- Planning permission for extensions · from £300
- Porch extensions · from £3,800
- Bungalow extensions · from £24,500
- Glass box extensions · from £28,500
- Bedroom extensions · from £24,500
- Extensions over a garage · from £22,500
- Double-storey extensions · from £36,000
- Flat roof extensions · from £19,500
- Pitched roof extensions · from £21,000
- Annexe extensions · from £52,000
- Side extensions · from £20,500
- Conservatory replacement extensions · from £19,000
- Orangery extensions · from £28,500
- Timber frame extensions · from £19,500
- Side return extensions · from £17,000
- Kitchen extensions · from £25,500
- Utility and boot room extensions · from £13,000
- Building regulations for extensions · from £850
Free site visit
We visit your Brackley home, measure up, talk through what you want and check the planning position.
Design and approvals
Drawings are prepared and agreed with you, then submitted for the right planning route and building regulations approval.
Fixed written price
With the design and specification agreed, you get a fixed written price and a start date.
Build and sign-off
Our team builds the extension, keeps you updated weekly and finishes with building control sign-off.
Questions about extensions in Brackley
How much does an extension cost in Brackley?
Using our East Midlands factor (×0.95), a standard-spec single-storey extension of 20 m² is a guide £38,500 to £49,500 including VAT, and a 32 m² two-storey extension £54,500 to £71,500. Your written price follows the survey.
Do you handle building regulations?
Yes. We prepare the drawings and calculations, submit them and book inspections, ending with a completion certificate.
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 you cover all of Brackley?
Yes, including the surrounding parts of Northamptonshire. Site visits are free and there is no obligation.
Book a free site visit in Brackley
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.