Home extensions in Leatherhead
From a small utility to a two-storey addition, we take on house extensions throughout Leatherhead, starting with a free visit and a planning check.
- Postcode districtsKT21, KT22, KT23
- Price regionSouth East England (×1.12)
- Planning rulesEngland
- Site visitFree, no obligation

What extensions cost in Leatherhead
We publish guide prices so you can budget before anyone visits. For Leatherhead they are adjusted by ×1.12, the factor we use across South East England.
| Extension type | Example size | Standard spec (inc VAT) |
|---|---|---|
| Conservatory replacement extensions | 14 m² | £33,500 – £43,500 |
| Extensions over a garage | 12 m² | £28,000 – £36,500 |
| Wraparound extensions | 25 m² | £64,000 – £81,500 |
| Double-storey extensions | 32 m² | £64,500 – £84,500 |
| Kitchen extensions | 20 m² | £47,000 – £59,500 |
| Side return extensions | 11 m² | £29,500 – £37,000 |
Areas we cover around Leatherhead
Site visits are available across Leatherhead (KT21, KT22, KT23). Nearby, we also take on projects in Epsom (4 miles), Ewell (5 miles), Esher (5 miles), Banstead (6 miles), Reigate (7 miles). Chessington, in Greater London, is roughly 5 miles from Leatherhead and also on our list.
Planning rules in Leatherhead
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.
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 Leatherhead houses?
Homes across the South East range from Victorian terraces in the older town centres to large detached houses on the edges, so the right extension type varies street by street.
Depending on the plot, double-storey extensions and wraparound extensions are often the strongest options, with orangery extensions worth considering where there is room.
Every extension type in Leatherhead
- Pitched roof extensions · from £24,500
- Extensions over a garage · from £26,500
- Porch extensions · from £4,450
- Wraparound extensions · from £40,000
- Kitchen extensions · from £30,000
- Single-storey rear extensions · from £23,500
- Extension plans and drawings · from £1,300
- Utility and boot room extensions · from £15,500
- Bungalow extensions · from £29,000
- Bedroom extensions · from £29,000
- Flat roof extensions · from £23,500
- Double-storey extensions · from £42,500
- Home office extensions · from £17,500
- Conservatory replacement extensions · from £22,000
- Glass box extensions · from £33,500
- Side return extensions · from £20,000
- Orangery extensions · from £33,500
- Side extensions · from £24,500
- Building regulations for extensions · from £1,000
- Planning permission for extensions · from £350
- Timber frame extensions · from £23,500
- Annexe extensions · from £61,500
Free site visit
A designer visits, takes measurements and photos, and discusses layouts, budget and timing with you.
Design and approvals
Drawings are prepared and agreed with you, then submitted for the right planning route and building regulations approval.
Fixed written price
You receive a written, itemised price and programme. Nothing starts until you are happy with it.
Build and sign-off
Our team builds the extension, keeps you updated weekly and finishes with building control sign-off.
Questions about extensions in Leatherhead
How much does an extension cost in Leatherhead?
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 Leatherhead?
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 Leatherhead?
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.
Book a free site visit in Leatherhead
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.