Extensions over a garage in Surbiton
A over-garage extension in Surbiton starts with the right design and the right approval route. We take care of both, then build it with our own project management.
- Guide price in SurbitonFrom £31,000 inc VAT
- PlanningHouseholder application needed
- Build time12–18 weeks on site
- Postcode districtsKT1, KT2, KT3, KT5, KT6
Planning and approvals in Surbiton
In England any side extension over one storey, including a room built over a side garage, needs a householder planning application. The fee is £548 from 1 April 2026 and councils aim to decide within 8 weeks.
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.
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 we take care of
- Strengthening or rebuilding the garage walls if needed
- New floor structure, walls and roof
- Insulation, electrics, heating and finish
- Structural survey of garage walls and foundations
Local to Surbiton
We cover Surbiton and the postcode districts KT1, KT2, KT3, KT5, KT6, KT9. Nearby, we also take on projects in Hook (2 miles), New Malden (2 miles), Chessington (2 miles), Worcester Park (2 miles).
For homes towards Surrey, East Molesey is around 2 miles away. In London, space is at a premium and gardens are often short, so side returns, wraparounds and carefully planned rear extensions tend to make the most of every metre.
What should I budget for an over-garage extension in Surbiton?
Prices below are for Surbiton, using the London factor of ×1.3. They are guide ranges including VAT for the build only, not a quote.
Typical rates in Surbiton: £2,340 to £4,420 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| Over a single garage 12 m² | £31,000 – £38,500 | £32,500 – £42,500 | £42,000 – £53,500 |
| Over a large single garage 16 m² | £37,000 – £46,000 | £43,500 – £56,500 | £56,000 – £71,000 |
| Over a double garage 24 m² | £56,000 – £69,000 | £65,500 – £84,500 | £84,000 – £106,500 |
Want a range for your exact size? The guide-price tool takes about a minute.
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
First, a site visit: we look at the house, garden, access and drains and listen to what you need.
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
We build it with one project manager, book the building control inspections and hand over the completion certificate.
Common questions in Surbiton
Do you cover all of Surbiton?
Yes. We cover Surbiton and the surrounding parts of Greater London. Site visits are free and there is no obligation.
Who do I contract with for an over-garage extension in Surbiton?
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.
Do I need building regulations approval in Surbiton?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
Does building over a garage need planning permission?
In England and the rest of the UK, adding a storey over a side garage almost always needs a planning application, because two-storey side extensions are outside permitted development.
Can my garage take the weight of a room on top?
Some can and some cannot. Many garages have a single-skin wall or shallow foundations. Our structural engineer checks this before we give a fixed price.
Book a free site visit in Surbiton
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.