Extension plans and drawings in Egham
We prepare extension plans and drawings for homes in Egham, as a stand-alone service or as the first stage of a design and build project.
- Guide price in EghamFrom £1,300 inc VAT
- PlanningWe find the right route for you
- Timescale2–6 weeks for drawings
- Postcode districtsGU25, TW18, TW20

Do I need planning permission in Egham?
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.
Homes in conservation areas, national parks, National Landscapes (formerly AONBs), the Broads and World Heritage Sites have tighter rules, so we always check the property's status and planning history before design starts.
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).
What it costs in Egham
Fees below are our Egham 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 |
Try the guide-price tool to see a range for your own size and finish.
Who this service is for
- Anyone who wants fixed designs before getting build prices
- Projects that need a planning application or other approval
- Homeowners at the very start of a project
Extensions in and around Egham
We cover Egham and the postcode districts GU25, TW18, TW20. Nearby, we also take on projects in Staines-upon-Thames (2 miles), Ashford, Surrey (4 miles), Weybridge (6 miles), Sunbury-on-Thames (6 miles).
Windsor, in Berkshire, is roughly 4 miles from Egham and also on our list. In the South East, plenty of houses have already been extended once, which makes checking the remaining permitted development allowance an important early step.
From first visit to completion
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
You receive a written, itemised price and programme. Nothing starts until you are happy with it.
Build and sign-off
Work is carried out to the agreed programme, inspected by building control and signed off at the end.
Questions answered
Do you cover all of Egham?
Yes. We cover Egham and the surrounding parts of Surrey. Site visits are free and there is no obligation.
Do I need building regulations approval in Egham?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Egham, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
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.
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.
Book a free site visit in Egham
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.