Extensions in Hornchurch: design, planning and build
From a small utility to a two-storey addition, we take on house extensions throughout Hornchurch, starting with a free visit and a planning check.
- Postcode districtsRM1, RM2, RM11, RM12, RM14
- Price regionLondon (×1.3)
- Planning rulesEngland
- Site visitFree, no obligation
Guide prices for Hornchurch
We publish guide prices so you can budget before anyone visits. For Hornchurch they are adjusted by ×1.3, the factor we use across London.
| Extension type | Example size | Standard spec (inc VAT) |
|---|---|---|
| Wraparound extensions | 25 m² | £74,500 – £94,500 |
| Orangery extensions | 16 m² | £58,000 – £73,000 |
| Conservatory replacement extensions | 14 m² | £39,000 – £50,500 |
| Single-storey rear extensions | 20 m² | £53,000 – £68,000 |
| Double-storey extensions | 32 m² | £74,500 – £98,000 |
Approvals for an extension in Hornchurch
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.
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 works best for Hornchurch houses?
In London, space is at a premium and gardens are often short, so side returns, wraparounds and carefully planned rear extensions tend to make the most of every metre.
The types we would usually look at first for a home in Hornchurch are wraparound extensions, glass box extensions and side return extensions, depending on the garden and how the house is laid out.
Where we work near Hornchurch
Postcode districts we cover around Hornchurch include RM1, RM2, RM11, RM12, RM14. Nearby, we also take on projects in Romford (2 miles), Dagenham (2 miles), Becontree (4 miles), Thamesmead (6 miles), Barking (6 miles). Just over the Essex border, South Ockendon is about 4 miles away.
Choose an extension type
- Bungalow extensions · from £34,000
- Side extensions · from £28,500
- Conservatory replacement extensions · from £26,000
- Wraparound extensions · from £46,500
- Home office extensions · from £20,500
- Extensions over a garage · from £31,000
- Side return extensions · from £23,000
- Porch extensions · from £5,200
- Pitched roof extensions · from £28,500
- Orangery extensions · from £39,000
- Double-storey extensions · from £49,000
- Timber frame extensions · from £27,000
- Planning permission for extensions · from £450
- Extension plans and drawings · from £1,550
- Single-storey rear extensions · from £27,000
- Annexe extensions · from £71,500
- Glass box extensions · from £39,000
- Kitchen extensions · from £35,000
- Building regulations for extensions · from £1,150
- Bedroom extensions · from £33,500
- Utility and boot room extensions · from £18,000
- Flat roof extensions · from £27,000
Free site visit
It starts with a visit to your house to measure, check access and talk through ideas and budget.
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
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 Hornchurch
How much does an extension cost in Hornchurch?
Using our London factor (×1.3), a standard-spec single-storey extension of 20 m² is a guide £53,000 to £68,000 including VAT, and a 32 m² two-storey extension £74,500 to £98,000. Your written price follows the survey.
Do you cover all of Hornchurch?
Yes, including the surrounding parts of Greater London. Site visits are free and there is no obligation.
Do I need planning permission for an extension in Hornchurch?
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.
Book a free site visit in Hornchurch
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.