Extensions over a garage in Swanage
Our design and build teams take on over-garage extensions in Swanage, from the first measured survey through planning and building control to the finished room.
- Guide price in SwanageFrom £24,000 inc VAT
- PlanningHouseholder application needed
- Build time12–18 weeks on site
- Postcode districtsBH19
Working in Swanage
Site visits are available across Swanage (BH19). Nearby, we also take on projects in Poole (7 miles), Bournemouth (9 miles), Christchurch (12 miles), Ferndown (14 miles).
Just over the Hampshire border, New Milton is about 17 miles away. In the South West, local stone, render and brick vary from town to town, so matching materials is a big part of designing an extension that looks right.
What should I budget for an over-garage extension in Swanage?
For Swanage we adjust our national guide rates by ×1.02, the factor we use for South West England. Figures include VAT; your written quote after the survey replaces them.
Typical rates in Swanage: £1,840 to £3,470 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| Over a single garage 12 m² | £24,000 – £30,000 | £25,500 – £33,500 | £33,000 – £42,000 |
| Over a large single garage 16 m² | £29,000 – £36,000 | £34,000 – £44,500 | £44,000 – £55,500 |
| Over a double garage 24 m² | £44,000 – £54,000 | £51,000 – £66,500 | £66,000 – £83,500 |
Want a range for your exact size? The guide-price tool takes about a minute.
Will the council need to approve it?
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.
Applications are decided by the local planning authority (your district, borough or unitary council).
When an over-garage extension makes sense
- Families needing a bedroom without losing garden
- Homes where the landing can connect to the new room
- Detached and link-detached houses with an attached garage
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
A designer visits, takes measurements and photos, and discusses layouts, budget and timing with you.
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
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.
Common questions in Swanage
Do I need building regulations approval in Swanage?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
Who do I contract with for an over-garage extension in Swanage?
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 you cover all of Swanage?
Yes. We cover Swanage and the surrounding parts of Dorset. Site visits are free and there is no obligation.
Can I keep using the garage during the build?
Usually not for parking. The garage roof is removed and the space below is used for access and props for part of the build.
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.
Book a free site visit in Swanage
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.