Extension plans and drawings across Amersham
We prepare extension plans and drawings for homes in Amersham, as a stand-alone service or as the first stage of a design and build project.
- Guide price in AmershamFrom £1,300 inc VAT
- PlanningWe find the right route for you
- Timescale2–6 weeks for drawings
- Postcode districtsHP6, HP7

Planning rules that apply in Amersham
In England the main routes are permitted development (ideally confirmed with a lawful development certificate, £274), larger home extension prior approval (£249, 42 days) and a householder planning application (£548, normally 8 weeks), with council fees as set from 1 April 2026.
In a conservation area, national park, National Landscape, the Broads or a World Heritage Site the permitted development limits are tighter (no side or two-storey extensions without an application). Listed homes need listed building consent, and if permitted development rights have been removed, any extension needs an application.
Building over or within 3 m of a public sewer needs the water company's consent, usually through a build-over agreement, before the foundations go in.
Applications are decided by the local planning authority (your district, borough or unitary council).
Who this service is for
- Homeowners at the very start of a project
- Anyone who wants fixed designs before getting build prices
- Projects that need a planning application or other approval
The most expensive changes are the ones made after the steel is ordered. A good design stage settles layout, heights, glazing and services on paper, so the build price is firm.
What it costs in Amersham
Guide fees for Amersham including VAT, using our South East England factor of ×1.12. Council and building control charges are not included.
| Option | What it covers | Guide price |
|---|---|---|
| Essential | Measured survey and planning drawings | £1,300 – £2,500 |
| Standard | Planning drawings plus building regulations drawings | £2,450 – £4,300 |
| Premium | Full pack with structural calculations and 3D visuals | £3,800 – £6,200 |
For a figure based on your own dimensions, use our guide-price tool.
Working in Amersham
We cover Amersham and the postcode districts HP6, HP7. We also work in nearby Chesham (2 miles), Chalfont St Peter (5 miles), Gerrards Cross (6 miles), High Wycombe (6 miles).
Just over the Hertfordshire border, Rickmansworth is about 6 miles away. Homes across the South East range from Victorian terraces in the older town centres to large detached houses on the edges, so the right extension type varies street by street.
How the project works
Site visits are free and there is no obligation. Where drawings are needed, the design stage is priced in writing before it starts.
Free site visit
It starts with a visit to your house to measure, check access and talk through ideas and budget.
Design and approvals
Once the layout is agreed, we deal with the council: planning permission or written confirmation that none is needed, plus building control.
Fixed written price
The price is fixed in writing once the design is settled, with a clear programme and payment stages.
Build and sign-off
The build is managed from start to finish, inspected at each stage and signed off on completion.
Questions answered
Who do I contract with in Amersham?
Your contract is with S&K Property Investments and Improvement Ltd, which designs and manages the project and the build teams who carry it out.
How long does this take for a Amersham home?
2–6 weeks for drawings, depending on the council and the complexity of the project.
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Amersham, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
How much do extension plans cost?
Our design packs range from about £1,300 to £6,200 including VAT, from planning drawings only to a full pack with building regulations drawings, structural calculations and 3D views. Council fees are separate.
Can I use your drawings with another builder?
Yes. Once paid for, the drawings are yours to use for your project.
Book a free site visit in Amersham
We will measure up, check the planning position and give you honest guide figures.
- Free, no-obligation site visit
- Planning route checked before you spend on drawings
- Written price once the design is agreed
- Building control sign-off at the end
Prefer to talk? Call 0800 088 6341 or .
Book a free site visit
Tell us a little about the project and we will arrange a time.