House extensions in Southend-on-Sea
Planning an extension in Southend-on-Sea? Compare extension types, see guide prices adjusted for Southend-on-Sea and book a free site visit.
- Postcode districtsSS0, SS1, SS2, SS3, SS4, SS9
- Price regionEast of England (×1.06)
- Planning rulesEngland
- Site visitFree, no obligation
Do extensions in Southend-on-Sea need planning permission?
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 return infill is often permitted development if it stays within the height limits and is no wider than half the width of the original house. Conservation areas, listed buildings and flats always need an application, and the boundary wall usually brings in the Party Wall Act.
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).
What extensions cost in Southend-on-Sea
Every figure below is a guide for Southend-on-Sea, adjusted for East of England build costs (×1.06) and including VAT. Design and council fees are shown separately on each page.
| Extension type | Example size | Standard spec (inc VAT) |
|---|---|---|
| Double-storey extensions | 32 m² | £61,000 – £80,000 |
| Single-storey rear extensions | 20 m² | £43,000 – £55,500 |
| Wraparound extensions | 25 m² | £60,500 – £77,000 |
| Orangery extensions | 16 m² | £47,000 – £59,500 |
| Extensions over a garage | 12 m² | £26,500 – £34,500 |
| Side return extensions | 11 m² | £27,500 – £35,000 |
| Kitchen extensions | 20 m² | £44,500 – £56,500 |
Areas we cover around Southend-on-Sea
Our survey diary covers Southend-on-Sea, including SS0, SS1, SS2, SS3, SS4, SS9. Nearby, we also take on projects in Hadleigh (5 miles), Rayleigh (6 miles), Canvey Island (6 miles), Benfleet (7 miles), Wickford (10 miles). For homes towards Kent, Gillingham is around 13 miles away.
What works best for Southend-on-Sea houses?
Across the East of England many houses sit on generous plots, and single-storey and wraparound extensions are a natural fit.
For many houses here, bungalow extensions, wraparound extensions or double-storey extensions gives the most useful space for the budget.
All extension types we build in Southend-on-Sea
- Conservatory replacement extensions · from £21,000
- Annexe extensions · from £58,000
- Wraparound extensions · from £38,000
- Side return extensions · from £19,000
- Bungalow extensions · from £27,500
- Flat roof extensions · from £22,000
- Single-storey rear extensions · from £22,000
- Glass box extensions · from £31,500
- Extensions over a garage · from £25,000
- Kitchen extensions · from £28,500
- Double-storey extensions · from £40,000
- Side extensions · from £23,000
- Porch extensions · from £4,200
- Home office extensions · from £16,500
- Extension plans and drawings · from £1,250
- Building regulations for extensions · from £950
- Bedroom extensions · from £27,500
- Utility and boot room extensions · from £14,500
- Timber frame extensions · from £22,000
- Pitched roof extensions · from £23,500
- Orangery extensions · from £31,500
- Planning permission for extensions · from £350
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
With the design and specification agreed, you get a fixed written price and a start date.
Build and sign-off
Work is carried out to the agreed programme, inspected by building control and signed off at the end.
Questions about extensions in Southend-on-Sea
How much does an extension cost in Southend-on-Sea?
Using our East of England factor (×1.06), a standard-spec single-storey extension of 20 m² is a guide £43,000 to £55,500 including VAT, and a 32 m² two-storey extension £61,000 to £80,000. Your written price follows the survey.
Do you handle building regulations?
Yes. We prepare the drawings and calculations, submit them and book inspections, ending with a completion certificate.
Do I need planning permission for an extension in Southend-on-Sea?
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.
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.
How long does an extension take in Southend-on-Sea?
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.
Book a free site visit in Southend-on-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.