Amersham on the Hill, Buckinghamshire
Single-storey rear extension in Amersham on the Hill
Ground-floor space across the back of the house, usually for a kitchen, dining or family room. If you live in Amersham on the Hill and want to know what a single-storey rear extension would cost and whether it needs planning, start with the online guide price or a free site visit.
We cover Amersham on the Hill (HP5, HP6 and HP7) as part of our Buckinghamshire work. A single-storey rear extension in Amersham on the Hill 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 Amersham on the Hill?
In Amersham on the Hill, our guide for a single-storey rear extension is £2,130–£3,470 per square metre including VAT for a 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 |
Ground conditions, glazing, the roof and how far the house is opened up move the final figure within the range.
Do you need planning permission for a single-storey rear extension in Amersham on the Hill?
Planning for a single-storey rear extension in Amersham on the Hill 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.
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. 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 Amersham on the Hill like to extend?
Commuter semis and detached houses make up much of Amersham on the Hill, and longer gardens make England's prior approval route for deeper rear extensions worth considering.
How a single-storey rear extension in Amersham on the Hill comes together
Survey visit
We visit free of charge, measure up, check access, drainage and neighbours' extensions, and note what you want the room to do.
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.
Single-storey rear extensions near Amersham on the Hill
We also build single-storey rear extensions in nearby Amersham (0.7 miles) and Chesham (1.8 miles).
- Single-storey rear extension in Amersham
- Single-storey rear extension in Chesham
- Single-storey rear extension in Chorleywood
- Single-storey rear extension in Beaconsfield
- Single-storey rear extension in Chalfont St Peter
Other work in Amersham on the Hill:
FAQ
Single-storey rear extension questions in Amersham on the Hill
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.
Can you match the brick or stone on my Amersham on the Hill house?
We source the closest match and show you samples before ordering; reclaimed materials are often the best match on older houses.
Do I need a structural engineer?
Yes for the beam over the new opening and usually for the foundations. Their calculations go to building control with the drawings.
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.
What postcode areas do you cover around Amersham on the Hill?
Including HP5, HP6 and HP7, and the surrounding Buckinghamshire area.
Do I need planning permission for a rear extension in Amersham on the Hill?
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.