House extensions in Worthing
We design and build house extensions for homes in Worthing and the surrounding West Sussex area, with guide prices adjusted for the region.
- Postcode districtsBN11, BN12, BN13, BN14, BN15
- Price regionSouth East England (×1.12)
- Planning rulesEngland
- Site visitFree, no obligation
Planning rules in Worthing
In England a single-storey rear extension can usually go up to 3 m beyond the original rear wall of a semi-detached or terraced house, or 4 m on a detached house, without a planning application, provided it is no more than 4 m high, keeps eaves to 3 m within 2 m of a boundary and, with other buildings, covers no more than half the land around the original house. The larger home extension prior approval scheme raises those depths to 6 m and 8 m, with neighbours notified and a 42-day decision.
In England a single-storey side extension can be permitted development if it is no more than 4 m high and no wider than half the width of the original house. Two-storey side extensions, and any side extension on designated land such as a conservation area, need a householder planning application.
In a conservation area, national park, National Landscape, the Broads or a World Heritage Site the permitted development limits are tighter (no side or two-storey extensions without an application). Listed homes need listed building consent, and if permitted development rights have been removed, any extension needs an application.
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).
Where we work near Worthing
Across BN11, BN12, BN13, BN14, BN15, we can visit, measure and advise. We also work in nearby Lancing (2 miles), Shoreham-by-Sea (5 miles), Littlehampton (7 miles), Bognor Regis (14 miles), Burgess Hill (14 miles). For homes towards East Sussex, Portslade is around 7 miles away.
What extensions cost in Worthing
Use these Worthing guide prices to sense-check a budget; the guide-price tool narrows them to your own size, and the site visit turns them into a written figure.
| Extension type | Example size | Standard spec (inc VAT) |
|---|---|---|
| Wraparound extensions | 25 m² | £64,000 – £81,500 |
| Side return extensions | 11 m² | £29,500 – £37,000 |
| Conservatory replacement extensions | 14 m² | £33,500 – £43,500 |
| Kitchen extensions | 20 m² | £47,000 – £59,500 |
| Double-storey extensions | 32 m² | £64,500 – £84,500 |
What works best for Worthing houses?
In the South East, plenty of houses have already been extended once, which makes checking the remaining permitted development allowance an important early step.
The types we would usually look at first for a home in Worthing are wraparound extensions, double-storey extensions and single-storey rear extensions, depending on the garden and how the house is laid out.
Every extension type in Worthing
- Annexe extensions · from £61,500
- Glass box extensions · from £33,500
- Bedroom extensions · from £29,000
- Wraparound extensions · from £40,000
- Orangery extensions · from £33,500
- Extension plans and drawings · from £1,300
- Home office extensions · from £17,500
- Single-storey rear extensions · from £23,500
- Porch extensions · from £4,450
- Building regulations for extensions · from £1,000
- Bungalow extensions · from £29,000
- Side extensions · from £24,500
- Timber frame extensions · from £23,500
- Pitched roof extensions · from £24,500
- Side return extensions · from £20,000
- Utility and boot room extensions · from £15,500
- Extensions over a garage · from £26,500
- Conservatory replacement extensions · from £22,000
- Double-storey extensions · from £42,500
- Flat roof extensions · from £23,500
- Kitchen extensions · from £30,000
- Planning permission for extensions · from £350
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
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.
Questions about extensions in Worthing
How much does an extension cost in Worthing?
Using our South East England factor (×1.12), a standard-spec single-storey extension of 20 m² is a guide £45,500 to £58,500 including VAT, and a 32 m² two-storey extension £64,500 to £84,500. Your written price follows the survey.
Do I need planning permission for an extension in Worthing?
Not always. It depends on the size, position and your property's history. Many single-storey rear extensions in England are permitted development or can use prior approval.
How long does an extension take in Worthing?
Usually 2 to 4 months of design and approvals, then 10 to 16 weeks on site for a single-storey extension or 16 to 24 weeks for two storeys.
Will my neighbours need to be told?
If you apply for planning or prior approval the council notifies them, and in England party wall notices may be needed for work near a shared boundary.
Do you handle building regulations?
Yes. We prepare the drawings and calculations, submit them and book inspections, ending with a completion certificate.
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.