Extensions over a garage across Worthing
From the first sketch to final sign-off, we plan and build over-garage extensions in Worthing and the surrounding West Sussex area.
- Guide price in WorthingFrom £26,500 inc VAT
- PlanningHouseholder application needed
- Build time12–18 weeks on site
- Postcode districtsBN11, BN12, BN13, BN14, BN15
Planning rules that apply in Worthing
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.
The planning position for a specific Worthing 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.
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).
Over-garage extension prices in Worthing
Labour and material costs vary across the UK, so for Worthing we use our South East England factor (×1.12). The ranges include VAT and exclude design, structural and council fees.
Typical rates in Worthing: £2,020 to £3,810 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| Over a single garage 12 m² | £26,500 – £33,000 | £28,000 – £36,500 | £36,000 – £46,000 |
| Over a large single garage 16 m² | £32,000 – £39,500 | £37,500 – £48,500 | £48,000 – £61,000 |
| Over a double garage 24 m² | £48,000 – £59,500 | £56,000 – £73,000 | £72,500 – £91,500 |
For a figure based on your own dimensions, use our guide-price tool.
Working in Worthing
Postcode districts we cover around Worthing include BN11, BN12, BN13, BN14, BN15. Nearby, we also take on projects in Lancing (2 miles), Shoreham-by-Sea (5 miles), Littlehampton (7 miles), Bognor Regis (14 miles).
For homes towards East Sussex, Portslade is around 7 miles away. 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.
When an over-garage extension makes sense
- Homes where the landing can connect to the new room
- Families needing a bedroom without losing garden
- Detached and link-detached houses with an attached garage
Fitting the new room to the existing landing is the planning puzzle inside the house. We design the connection first, then the roof, so the extension does not end up with awkward steps or a corridor through a bedroom.
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
It starts with a visit to your house to measure, check access and talk through ideas and budget.
Design and approvals
We draw the design, agree it with you and handle planning or permitted development checks and building regulations.
Fixed written price
We confirm the build price in writing, based on the approved drawings and the finishes you have chosen.
Build and sign-off
The build is managed from start to finish, inspected at each stage and signed off on completion.
Your questions about an over-garage extension in Worthing
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Worthing, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
How long does an over-garage extension take to build in Worthing?
On site, typically 12 to 18 weeks once approvals are in place. Before that, allow 8–14 weeks design and approvals.
Do you cover all of Worthing?
Yes. We cover Worthing and the surrounding parts of West Sussex. 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 Worthing
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.