House extensions in Essex
More space without moving: we plan and build extensions across Essex, with one team for the drawings, the council and the build.
- Towns listed21
- Price regionEast of England (×1.06)
- Planning rulesEngland
- Postcode districts68
Towns we cover in Essex
Towns we cover here include Southend-on-Sea, Basildon, Colchester, Chelmsford.
Approvals for an extension in Essex
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 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.
What extensions cost in Essex
Every figure below is a guide for Essex, 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) |
|---|---|---|
| Wraparound extensions | 25 m² | £60,500 – £77,000 |
| Orangery extensions | 16 m² | £47,000 – £59,500 |
| Kitchen extensions | 20 m² | £44,500 – £56,500 |
| Double-storey extensions | 32 m² | £61,000 – £80,000 |
| Extensions over a garage | 12 m² | £26,500 – £34,500 |
What works best for Essex houses?
Across the East of England many houses sit on generous plots, and single-storey and wraparound extensions are a natural fit.
The types we would usually look at first for a home in Essex are double-storey extensions, single-storey rear extensions and bungalow extensions, depending on the garden and how the house is laid out.
Extension types and starting prices
- Building regulations for extensions · from £950
- Bedroom extensions · from £27,500
- Planning permission for extensions · from £350
- Orangery extensions · from £31,500
- Extension plans and drawings · from £1,250
- Double-storey extensions · from £40,000
- Home office extensions · from £16,500
- Single-storey rear extensions · from £22,000
- Porch extensions · from £4,200
- Flat roof extensions · from £22,000
- Bungalow extensions · from £27,500
- Kitchen extensions · from £28,500
- Side return extensions · from £19,000
- Conservatory replacement extensions · from £21,000
- Wraparound extensions · from £38,000
- Utility and boot room extensions · from £14,500
- Timber frame extensions · from £22,000
- Side extensions · from £23,000
- Annexe extensions · from £58,000
- Glass box extensions · from £31,500
- Pitched roof extensions · from £23,500
- Extensions over a garage · from £25,000
Neighbouring areas
Questions about extensions in Essex
How much does an extension cost in Essex?
With our East of England factor (×1.06), a standard-spec 20 m² single-storey extension is a guide £43,000 to £55,500 including VAT. Prices for every type are linked on this page.
Do you cover all of Essex?
Yes, across the whole of Essex. 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.
Do I need planning permission for an extension in Essex?
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.
Book a free site visit in Essex
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.