Hampshire
Kitchen-diner rear extensions in Hampshire
An open-plan kitchen, dining and family room that opens straight onto the garden. Rear extensions in Hampshire: we cover 34 towns including Southampton, Portsmouth and Basingstoke, with design, approvals and the build under one contract.

A kitchen-diner is often the reason people in Southampton extend: the back kitchen in commuter semis and detached houses is rarely big enough for a table. Commuter semis and detached houses make up much of Hampshire, and longer gardens make England's prior approval route for deeper rear extensions worth considering.
How much does a kitchen-diner rear extension cost in Hampshire?
For Hampshire we work from the South East England rate: £2,130–£3,470 per square metre of new floor, including VAT, standard specification. South East prices run above our West Midlands baseline, mainly on labour rates and clay-soil foundations.
| Size | Guide price inc VAT |
|---|---|
| 3 m wide × 4 m deep (12 m²) | £25,500–£41,500 |
| 4 m wide × 5 m deep (20 m²) | £42,500–£69,500 |
| 4 m wide × 6 m deep (24 m²) | £51,000–£83,500 |
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 in Hampshire?
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.
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.
Where in Hampshire do we work?
FAQ
Questions people ask
Should the sink face the garden?
If the plan allows, an island sink or hob facing the glass is a common choice. It needs a floor-level drain run, which is easy to lay in a new slab.
Can I have underfloor heating?
Yes. Wet underfloor heating in the new screed is the usual choice, often with the old room's radiators kept or replaced.
Where does the cooker extraction go?
Through the new wall or roof, ducted to outside. Recirculating hoods are possible but less effective.
Do you cover all of Hampshire?
We cover 34 towns and districts in Hampshire, including Southampton, Portsmouth and Basingstoke.
Who builds the extension?
Vetted building teams working under contract to us; your contract is with S&K Property Investments and Improvement Ltd.