Extensions over a garage in Melksham
A over-garage extension in Melksham 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 MelkshamFrom £24,000 inc VAT
- PlanningHouseholder application needed
- Build time12–18 weeks on site
- Postcode districtsSN12
Guide prices for Melksham
These guide figures apply our South West England adjustment (×1.02) to national rates. They include VAT at 20% and cover the build itself; design and council fees are listed separately.
Typical rates in Melksham: £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.
What is included
- New floor structure, walls and roof
- Strengthening or rebuilding the garage walls if needed
- Opening into the existing first floor
- Structural survey of garage walls and foundations
Working in Melksham
Site visits are available across Melksham (SN12). Nearby, we also take on projects in Trowbridge (5 miles), Chippenham (6 miles), Devizes (7 miles), Calne (8 miles).
Just over the Somerset border, Bath is about 10 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.
Do I need planning permission in Melksham?
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 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.
If the work involves a shared wall, building on the boundary, or digging foundations within 3 m (sometimes 6 m) of a neighbour's building, the Party Wall etc. Act 1996 applies and notice must be served before work starts: two months for work to a party wall, one month for new walls on the boundary and for excavations.
Applications are decided by the local planning authority (your district, borough or unitary council).
How the project works
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 draw the design, agree it with you and handle planning or permitted development checks and building regulations.
Fixed written price
You receive a written, itemised price and programme. Nothing starts until you are happy with it.
Build and sign-off
The build is managed from start to finish, inspected at each stage and signed off on completion.
Over-garage extension questions answered
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Melksham, 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 Melksham?
Yes. We cover Melksham and the surrounding parts of Wiltshire. Site visits are free and there is no obligation.
Who do I contract with for an over-garage extension in Melksham?
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.
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.
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 Melksham
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.