Northamptonshire
Two-storey rear extensions in Northamptonshire
A larger kitchen downstairs and an extra bedroom or bathroom upstairs, under one roof. Rear extensions in Northamptonshire: we cover 8 towns including Northampton, Corby and Kettering, with design, approvals and the build under one contract.
In Northamptonshire we check the neighbours' rear windows first, because the upper floor is where most two-storey schemes win or lose planning. Northamptonshire has plenty of inter-war semis and bungalows, and single-storey rear extensions suit both.
How much does a two-storey rear extension cost in Northamptonshire?
Guide prices for a two-storey rear extension in Northamptonshire start from our East Midlands rate of £1,750–£2,620 per square metre, including VAT. East Midlands prices sit a little below our West Midlands baseline.
| Size | Guide price inc VAT |
|---|---|
| 3 m × 5 m footprint, two floors (30 m²) | £52,500–£78,500 |
| 4 m × 6 m footprint, two floors (48 m²) | £84,000–£125,500 |
Your written price follows a measured survey and an agreed design, so it reflects your house, not an average.
Do you need planning permission in Northamptonshire?
England's rules allow a rear extension of more than one storey without an application only when it is no deeper than 3 metres and at least 7 metres from the boundary opposite the rear wall, and never on designated land. Most two-storey schemes need householder planning permission.
Conservation areas, National Parks, National Landscapes and the Broads restrict permitted development, and listed buildings always need listed building consent.
Where in Northamptonshire do we work?
FAQ
Questions people ask
Does a two-storey rear extension need planning permission?
Almost always. England and Northern Ireland allow 3 metres without an application only if at least 7 metres remains to the rear boundary; Wales and Scotland are similar or stricter.
Is two-storey cheaper per square metre than single-storey?
Usually yes, because the foundations and roof are shared across twice the floor area. The total cost is higher.
Can I add an en-suite upstairs?
Yes. We plan the soil pipe route early so the bathroom sits where drainage works without boxing through the room below.
Do you cover all of Northamptonshire?
We cover 8 towns and districts in Northamptonshire, including Northampton, Corby and Kettering.
Who builds the extension?
Vetted building teams working under contract to us; your contract is with S&K Property Investments and Improvement Ltd.