Bungalow extensions in Sunbury-on-Thames: design, approvals and build
If you live in Sunbury-on-Thames and want more space without moving, a bungalow extension is one of the most practical ways to get it. We handle the drawings, approvals and the build.
- Guide price in Sunbury-on-ThamesFrom £29,000 inc VAT
- PlanningSingle storey often permitted development
- Build time10–18 weeks on site
- Postcode districtsKT12, TW16, TW17
Extensions in and around Sunbury-on-Thames
Across KT12, TW16, TW17, we can visit, measure and advise. The same team covers Walton-on-Thames (1 mile), West Molesey (2 miles), Ashford, Surrey (3 miles), Weybridge (3 miles), all within easy reach.
Hampton, in Greater London, is roughly 2 miles from Sunbury-on-Thames and also on our list. 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.
Included in a typical project
- Single-storey extension options assessed first
- Level thresholds and accessible layouts
- Roof designs that tie into the existing hipped or gable roof
- Structural survey before any upward extension
Planning and approvals in Sunbury-on-Thames
In England a single-storey extension to a bungalow follows the normal permitted development limits (3 m or 4 m, or 6 m and 8 m through prior approval). Adding a first floor always needs planning permission.
Before any drawing is finalised we check whether the house is listed, in a conservation area or subject to an Article 4 direction.
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).
What should I budget for a bungalow extension in Sunbury-on-Thames?
Labour and material costs vary across the UK, so for Sunbury-on-Thames we use our South East England factor (×1.12). The ranges include VAT and exclude design, structural and council fees.
Typical rates in Sunbury-on-Thames: £1,960 to £3,810 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 3 m × 5 m 15 m² | £29,000 – £35,500 | £34,000 – £45,000 | £43,500 – £57,500 |
| 4 m × 6 m 24 m² | £47,000 – £56,500 | £55,000 – £71,500 | £69,500 – £91,500 |
| L-shape 35 m² | £68,500 – £82,500 | £80,000 – £104,000 | £101,500 – £133,500 |
Try the guide-price tool to see a range for your own size and finish.
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
A designer visits, takes measurements and photos, and discusses layouts, budget and timing with you.
Design and approvals
Drawings are prepared and agreed with you, then submitted for the right planning route and building regulations approval.
Fixed written price
With the design and specification agreed, you get a fixed written price and a start date.
Build and sign-off
We build it with one project manager, book the building control inspections and hand over the completion certificate.
Bungalow extension questions answered
Will my neighbours in Sunbury-on-Thames 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 Sunbury-on-Thames?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
Do you cover all of Sunbury-on-Thames?
Yes. We cover Sunbury-on-Thames and the surrounding parts of Surrey. Site visits are free and there is no obligation.
Is it better to extend sideways or upwards?
Sideways and rearwards is usually simpler, cheaper and keeps single-level living. Upwards saves garden but means stairs, more structure and planning permission.
How much does a bungalow extension cost?
Our guide range for single-storey work is about £1,960 to £3,810 per m² including VAT. Going upwards is priced after a structural survey.
Book a free site visit in Sunbury-on-Thames
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.