Extension plans and drawings in Swindon
For Swindon homeowners we handle extension plans and drawings, with fees agreed in writing before any work starts.
- Guide price in SwindonFrom £1,200 inc VAT
- PlanningWe find the right route for you
- Timescale2–6 weeks for drawings
- Postcode districtsSN1, SN2, SN3, SN4, SN5
Extensions in and around Swindon
Across SN1, SN2, SN3, SN4, SN5, SN25, we can visit, measure and advise. Nearby, we also take on projects in Calne (12 miles), Chippenham (16 miles), Devizes (18 miles), Melksham (20 miles).
Cirencester, in Gloucestershire, is roughly 14 miles from Swindon and also on our list. South West homes range from terraced streets in the cities to stone cottages and bungalows in the countryside, and conservation areas are common in historic centres.
What it costs in Swindon
Fees below are our Swindon guide (×1.02, the South West England factor), including VAT. Council and building control fees are extra.
| Option | What it covers | Guide price |
|---|---|---|
| Essential | Measured survey and planning drawings | £1,200 – £2,250 |
| Standard | Planning drawings plus building regulations drawings | £2,200 – £3,900 |
| Premium | Full pack with structural calculations and 3D visuals | £3,450 – £5,650 |
Try the guide-price tool to see a range for your own size and finish.
Planning and approvals in Swindon
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.
The planning position for a specific Swindon address depends on its history and any designations, which is why we check it at the first visit.
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).
When it helps
- 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 happens next
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 Swindon home, measure up, talk through what you want and check the planning position.
Design and approvals
We draw the design, agree it with you and handle planning or permitted development checks and building regulations.
Fixed written price
With the design and specification agreed, you get a fixed written price and a start date.
Build and sign-off
Work is carried out to the agreed programme, inspected by building control and signed off at the end.
Common questions in Swindon
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Swindon, 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 you cover all of Swindon?
Yes. We cover Swindon and the surrounding parts of Wiltshire. Site visits are free and there is no obligation.
Do I need building regulations approval in Swindon?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
Can I use your drawings with another builder?
Yes. Once paid for, the drawings are yours to use for your project.
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.
Book a free site visit in Swindon
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.