Extension plans and drawings across Surrey
We prepare extension plans and drawings for homes across Surrey, on their own or as the first stage of a full design and build project.
- Guide priceFrom £1,300 inc VAT
- PlanningWe find the right route for you
- Towns covered22
- Site visitFree, no obligation

Towns in Surrey
Included in a typical project
- Structural calculations from an engineer (full pack)
- Planning drawings: existing and proposed plans and elevations, site and location plans
- Two or three layout options to compare
- 3D views to check the look and the light (full pack)
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 Surrey
Fees below are our Surrey guide (×1.12, the South East England factor), including VAT. Council and building control fees are extra.
| 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 |
Want a range for your exact size? The guide-price tool takes about a minute.
Extensions in and around Surrey
Towns we cover in Surrey include Woking, Guildford, Esher, Redhill, Staines-upon-Thames, Banstead, Leatherhead, Ewell. In the South East, plenty of houses have already been extended once, which makes checking the remaining permitted development allowance an important early step.
Planning and approvals in Surrey
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.
Building regulations approval is separate from planning. In England you can use the council's building control team or a registered building control approver; a full plans application gets the drawings checked before work starts, and the inspector signs the work off with a completion certificate.
Applications are decided by the local planning authority (your district, borough or unitary council).
Our process, step by step
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
We visit your Surrey home, measure up, talk through what you want and check the planning position.
Design and approvals
We produce the drawings and structural design, and manage the approvals so they are in place before work starts.
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
We build it with one project manager, book the building control inspections and hand over the completion certificate.
Common questions in Surrey
Who do I contract with in Surrey?
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.
Will my neighbours in Surrey be involved?
If a planning application or prior approval is needed, the council notifies neighbours. If the work is on or near a shared boundary, party wall notices may also be needed.
Do I need building regulations approval in Surrey?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
Do I need an architect?
Not necessarily. For most extensions an experienced designer or architectural technologist is enough. For listed buildings or complex sites an architect’s input can help.
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 Surrey
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.