Kettering, Northamptonshire
Single-storey rear extension in Kettering
For homes in Kettering, a single-storey rear extension is often the simplest way to gain space without moving. Ground-floor space across the back of the house, usually for a kitchen, dining or family room. We take it from survey to completion certificate.
Kettering is covered from our Northamptonshire round, including NN15 and NN16. A single-storey rear extension in Kettering is mostly built from the garden side, so the house stays usable for most of the job.
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 single-storey rear extension cost in Kettering?
For Kettering we work from the East Midlands rate: £1,840–£3,010 per square metre of new floor, including VAT, 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 |
Your written price follows a measured survey and an agreed design, so it reflects your house, not an average.
Do you need planning permission for a single-storey rear extension in Kettering?
Planning for a single-storey rear extension in Kettering follows the English householder rules.
In England a single-storey rear extension can often be built under permitted development: up to 3 metres beyond the original rear wall of an attached house, or 4 metres on a detached house, no higher than 4 metres, with eaves no higher than 3 metres if any part is within 2 metres of a boundary.
England also has the larger home extension route: a single-storey rear extension of up to 6 metres on an attached house or 8 metres on a detached house, after prior approval from the council. The council notifies your neighbours and has 42 days to decide; the fee is £249 (£310 for applications made from 8 December 2026). The route is not available on designated land such as conservation areas.
Conservation areas, National Parks, National Landscapes and the Broads restrict permitted development, and listed buildings always need listed building consent. At the first visit we measure what is there now and tell you which route fits: permitted development, prior approval or a planning application.
What are homes in Kettering like to extend?
Red-brick terraces and semis are typical of Kettering. Coal-mining legacy areas in parts of the East Midlands can need a Coal Authority check before foundations are designed.
How a single-storey rear extension in Kettering 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.
Paperwork handled
Planning, prior approval or permitted development, Building Regulations approval, structural design and party wall notices are all handled by us.
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.
Single-storey rear extensions near Kettering
We also build single-storey rear extensions in nearby Desborough (5.0 miles) and Wellingborough (6.7 miles).
- Single-storey rear extension in Desborough
- Single-storey rear extension in Wellingborough
- Single-storey rear extension in Corby
- Single-storey rear extension in Rushden
- Single-storey rear extension in Market Harborough
Other work in Kettering:
FAQ
Single-storey rear extension questions in Kettering
Do I need a party wall agreement?
In England, usually yes if the extension is on or near a shared boundary or the foundations are close to a neighbour's building. We serve the notices.
Can I get a price without a visit?
Our online guide-price tool gives a range in a couple of minutes. A written price needs a survey.
Will the extension make the room behind it dark?
Not if it is designed well. Rooflights or a lantern over the old back room, and a wide opening into it, keep daylight reaching the middle of the house.
Do I need planning permission for a rear extension in Kettering?
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.
Will I need a structural engineer?
Yes for the beam over the new opening and usually the foundations; we arrange them and their calculations go to building control.
How much does a single-storey rear extension cost in Kettering?
As a guide, £1,840–£3,010 per square metre including VAT for a standard specification. For example, 3 m wide × 4 m deep (12 m²): about £22,000–£36,000 at that rate. Your written price follows the survey.