Shoreham-by-Sea house extensions
From a small utility to a two-storey addition, we take on house extensions throughout Shoreham-by-Sea, starting with a free visit and a planning check.
- Postcode districtsBN42, BN43
- Price regionSouth East England (×1.12)
- Planning rulesEngland
- Site visitFree, no obligation
Approvals for an extension in Shoreham-by-Sea
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 two-storey rear extension is permitted development only if it projects no more than 3 m from the original rear wall, sits at least 7 m from the rear boundary, matches the roof pitch and uses obscure, non-opening side windows upstairs. Most two-storey extensions therefore go through a householder planning application, which costs £548 from 1 April 2026 and normally takes about 8 weeks.
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.
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).
What works best for Shoreham-by-Sea 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.
For many houses here, single-storey rear extensions, double-storey extensions or wraparound extensions gives the most useful space for the budget.
What extensions cost in Shoreham-by-Sea
Every figure below is a guide for Shoreham-by-Sea, adjusted for South East England build costs (×1.12) and including VAT. Design and council fees are shown separately on each page.
| Extension type | Example size | Standard spec (inc VAT) |
|---|---|---|
| Orangery extensions | 16 m² | £50,000 – £63,000 |
| Wraparound extensions | 25 m² | £64,000 – £81,500 |
| Conservatory replacement extensions | 14 m² | £33,500 – £43,500 |
| Kitchen extensions | 20 m² | £47,000 – £59,500 |
| Single-storey rear extensions | 20 m² | £45,500 – £58,500 |
Areas we cover around Shoreham-by-Sea
Site visits are available across Shoreham-by-Sea (BN42, BN43). The same team covers Lancing (2 miles), Worthing (5 miles), Burgess Hill (11 miles), Littlehampton (12 miles), Haywards Heath (14 miles), all within easy reach. Just over the East Sussex border, Portslade is about 3 miles away.
Extension types and starting prices
- Extensions over a garage · from £26,500
- Building regulations for extensions · from £1,000
- Kitchen extensions · from £30,000
- Conservatory replacement extensions · from £22,000
- Utility and boot room extensions · from £15,500
- Pitched roof extensions · from £24,500
- Bedroom extensions · from £29,000
- Extension plans and drawings · from £1,300
- Flat roof extensions · from £23,500
- Bungalow extensions · from £29,000
- Wraparound extensions · from £40,000
- Double-storey extensions · from £42,500
- Orangery extensions · from £33,500
- Side extensions · from £24,500
- Planning permission for extensions · from £350
- Annexe extensions · from £61,500
- Glass box extensions · from £33,500
- Home office extensions · from £17,500
- Timber frame extensions · from £23,500
- Single-storey rear extensions · from £23,500
- Side return extensions · from £20,000
- Porch extensions · from £4,450
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
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.
Questions about extensions in Shoreham-by-Sea
How much does an extension cost in Shoreham-by-Sea?
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.
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 cover all of Shoreham-by-Sea?
Yes, including the surrounding parts of West Sussex. Site visits are free and there is no obligation.
Who do I contract with?
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.
Book a free site visit in Shoreham-by-Sea
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.