Extensions in Daventry: design, planning and build
Every type of house extension in Daventry, from single-storey kitchen extensions to two-storey additions, side returns and orangeries. We design, handle the approvals and build.
- Postcode districtsNN11
- Price regionEast Midlands (×0.95)
- Planning rulesEngland
- Site visitFree, no obligation
Choosing the right extension in Daventry
Homes across the East Midlands often have usable side land or a driveway beside the house, which opens up side and wraparound options.
The types we would usually look at first for a home in Daventry are side extensions, double-storey extensions and conservatory replacement extensions, depending on the garden and how the house is laid out.
Planning and building control in Daventry
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).
Areas we cover around Daventry
Across NN11, we can visit, measure and advise. The same team covers Towcester (11 miles), Northampton (12 miles), Brackley (16 miles), Market Harborough (18 miles), Wellingborough (20 miles), all within easy reach. Rugby, in Warwickshire, is roughly 9 miles from Daventry and also on our list.
Daventry extension prices at a glance
Prices on this page use our East Midlands factor of ×0.95, 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) |
|---|---|---|
| Extensions over a garage | 12 m² | £23,500 – £31,000 |
| Double-storey extensions | 32 m² | £54,500 – £71,500 |
| Orangery extensions | 16 m² | £42,500 – £53,500 |
| Side return extensions | 11 m² | £25,000 – £31,500 |
| Single-storey rear extensions | 20 m² | £38,500 – £49,500 |
| Conservatory replacement extensions | 14 m² | £28,500 – £37,000 |
| Wraparound extensions | 25 m² | £54,500 – £69,000 |
Every extension type in Daventry
- Planning permission for extensions · from £300
- Conservatory replacement extensions · from £19,000
- Side return extensions · from £17,000
- Double-storey extensions · from £36,000
- Bungalow extensions · from £24,500
- Side extensions · from £20,500
- Building regulations for extensions · from £850
- Porch extensions · from £3,800
- Bedroom extensions · from £24,500
- Orangery extensions · from £28,500
- Utility and boot room extensions · from £13,000
- Pitched roof extensions · from £21,000
- Single-storey rear extensions · from £19,500
- Flat roof extensions · from £19,500
- Extensions over a garage · from £22,500
- Kitchen extensions · from £25,500
- Wraparound extensions · from £34,000
- Home office extensions · from £15,000
- Glass box extensions · from £28,500
- Extension plans and drawings · from £1,100
- Timber frame extensions · from £19,500
- Annexe extensions · from £52,000
Free site visit
First, a site visit: we look at the house, garden, access and drains and listen to what you need.
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
We build it with one project manager, book the building control inspections and hand over the completion certificate.
Questions about extensions in Daventry
How much does an extension cost in Daventry?
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.
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.
How long does an extension take in Daventry?
Usually 2 to 4 months of design and approvals, then 10 to 16 weeks on site for a single-storey extension or 16 to 24 weeks for two storeys.
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.
Book a free site visit in Daventry
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.