Northampton, Northamptonshire
Kitchen-diner rear extension in Northampton
We plan and build kitchen-diner rear extensions for homeowners in Northampton. An open-plan kitchen, dining and family room that opens straight onto the garden. Start with a free site visit, then a written price once the design is agreed.
Northampton sits in Northamptonshire, with postcode districts including NN1, NN2, NN3 and NN4. For Northampton kitchens we plan the extraction route and the island drainage before the slab is poured, so nothing has to be chased in later.
Book a free site visit
Tell us about the house and we'll call to arrange a free, no-obligation visit.
How much does a kitchen-diner rear extension cost in Northampton?
In Northampton, our guide for a kitchen-diner rear extension is £1,840–£3,010 per square metre including VAT for a standard specification. East Midlands prices sit a little below our West Midlands baseline.
| Size | Guide price inc VAT |
|---|---|
| 3 m wide × 4 m deep (12 m²) | £22,000–£36,000 |
| 4 m wide × 5 m deep (20 m²) | £37,000–£60,000 |
| 4 m wide × 6 m deep (24 m²) | £44,000–£72,000 |
We put a fixed price in writing once the design is agreed, and explain any provisional sums such as foundations.
Do you need planning permission for a kitchen-diner rear extension in Northampton?
Planning for a kitchen-diner rear extension in Northampton follows the English householder rules.
English permitted development (Class A) allows a single-storey rear extension of 3 metres on a terraced or semi-detached house and 4 metres on a detached one, measured from the original house, with a maximum height of 4 metres and eaves of no more than 3 metres within 2 metres of a boundary.
If 3 or 4 metres is not enough, England's prior approval route allows 6 metres on a terraced or semi-detached house and 8 metres on a detached house for a single-storey rear extension. Neighbours are consulted, the council decides within 42 days, and the fee is £249, rising to £310 from 8 December 2026.
Conservation areas, National Parks, National Landscapes and the Broads restrict permitted development, and listed buildings always need listed building consent. Before any drawing we look up the property's history with the council, because earlier extensions and removed rights change the answer.
What are homes in Northampton like to extend?
Northampton has plenty of inter-war semis and bungalows, and single-storey rear extensions suit both.
How a kitchen-diner rear extension in Northampton comes together
Look round and measure
A free visit to see the back of the house, measure it, check the drains and boundaries and hear what you need.
Drawings and budget
Floor plans and elevations for the options, each with a guide price.
Approvals
Permitted development check, prior approval or planning application, then Building Regulations drawings and structural calculations, plus party wall notices where they apply.
Fixed price and build
A written price for the agreed design, a start date and a named contact through the build, ending with the building control completion certificate.
Kitchen-diner rear extensions near Northampton
Close by, we work in Wellingborough, about 8.8 miles away, and Daventry, about 11.7 miles away.
- Kitchen-diner rear extension in Wellingborough
- Kitchen-diner rear extension in Daventry
- Kitchen-diner rear extension in Rushden
- Kitchen-diner rear extension in Kettering
- Kitchen-diner rear extension in Newport Pagnell
Other work in Northampton:
FAQ
Kitchen-diner rear extension questions in Northampton
Do I need planning permission for a rear extension in Northampton?
Often not for a single-storey rear extension of up to 3 metres (4 metres on a detached house) under permitted development, or up to 6 or 8 metres with prior approval, unless the house is in a conservation area or its rights have been removed.
How long does a rear extension take to build in Northampton?
Most single-storey rear extensions take 10 to 16 weeks on site and two-storey extensions 16 to 26 weeks, after design and approvals.
Can I add a utility room?
Often. A narrow utility or boot room along one side keeps the washing machine out of the open-plan space.
Can I live at home while the extension is built?
Usually yes. Most of the work is outside until the back wall is opened near the end, and that stage is screened off.
Who will build my extension?
Vetted building teams working under contract to us. Your contract is with S&K Property Investments and Improvement Ltd for the design and the build.
Do you handle building control in Northampton?
Yes. We apply to the council or a registered building control approver and hand over the completion certificate.