Berkshire
Rear extensions for detached houses in Berkshire
Wider, deeper rear extensions with room for vaulted roofs and big glazing. Rear extensions in Berkshire: we cover 14 towns including Reading, Slough and Bracknell, with design, approvals and the build under one contract.
Detached houses in Berkshire often have room for a deeper rear extension under England's prior approval route or a full-width design. Commuter semis and detached houses make up much of Berkshire, and longer gardens make England's prior approval route for deeper rear extensions worth considering.
How much does a detached house rear extension cost in Berkshire?
For Berkshire we work from the South East England rate: £2,180–£3,580 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 |
|---|---|
| 4 m wide × 6 m deep (24 m²) | £52,500–£86,000 |
| 5 m wide × 8 m deep (40 m²) | £87,500–£143,500 |
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 Berkshire?
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.
A two-storey rear extension can be permitted development in England only if it projects no more than 3 metres, stays at least 7 metres from the rear boundary, matches the existing roof pitch and has obscure-glazed upper side windows. In practice most double-storey rear extensions go through a householder planning application.
Conservation areas, National Parks, National Landscapes and the Broads restrict permitted development, and listed buildings always need listed building consent.
Where in Berkshire do we work?
FAQ
Questions people ask
How deep can I extend a detached house?
4 metres under permitted development in England, or 8 metres with prior approval, outside designated land.
Can I have a vaulted ceiling?
Yes, with a pitched roof and exposed or boxed rafters, subject to the height limits.
Is an oak frame worth it?
It is a premium finish with a long life; it costs more than blockwork with a plain roof.
Do you cover all of Berkshire?
We cover 14 towns and districts in Berkshire, including Reading, Slough and Bracknell.
Who builds the extension?
Vetted building teams working under contract to us; your contract is with S&K Property Investments and Improvement Ltd.