Extensions in New Cross: design, planning and build
Every type of house extension in New Cross, from single-storey kitchen extensions to two-storey additions, side returns and orangeries. We design, handle the approvals and build.
- Postcode districtsSE4, SE8, SE10, SE14, SE15, SE16
- Price regionLondon (×1.3)
- Planning rulesEngland
- Site visitFree, no obligation
Planning rules in New Cross
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 works best for New Cross houses?
London's housing is dominated by Victorian and Edwardian terraces, many with a rear outrigger and a side return, and 1930s semis in the outer boroughs. Conservation areas are common, so the planning check comes first.
The types we would usually look at first for a home in New Cross are wraparound extensions, kitchen extensions and glass box extensions, depending on the garden and how the house is laid out.
New Cross and surrounding towns
Postcode districts we cover around New Cross include SE4, SE8, SE10, SE14, SE15, SE16. We also work in nearby Brockley (1 mile), Greenwich (1 mile), Peckham (1 mile), Blackheath (2 miles), Catford (2 miles). For homes towards Kent, Swanley is around 11 miles away.
New Cross extension prices at a glance
Use these New Cross guide prices to sense-check a budget; the guide-price tool narrows them to your own size, and the site visit turns them into a written figure.
| Extension type | Example size | Standard spec (inc VAT) |
|---|---|---|
| Conservatory replacement extensions | 14 m² | £39,000 – £50,500 |
| Orangery extensions | 16 m² | £58,000 – £73,000 |
| Side return extensions | 11 m² | £34,000 – £43,000 |
| Single-storey rear extensions | 20 m² | £53,000 – £68,000 |
| Extensions over a garage | 12 m² | £32,500 – £42,500 |
| Double-storey extensions | 32 m² | £74,500 – £98,000 |
| Wraparound extensions | 25 m² | £74,500 – £94,500 |
All extension types we build in New Cross
- Wraparound extensions · from £46,500
- Orangery extensions · from £39,000
- Timber frame extensions · from £27,000
- Utility and boot room extensions · from £18,000
- Side extensions · from £28,500
- Porch extensions · from £5,200
- Planning permission for extensions · from £450
- Bedroom extensions · from £33,500
- Annexe extensions · from £71,500
- Extensions over a garage · from £31,000
- Flat roof extensions · from £27,000
- Building regulations for extensions · from £1,150
- Side return extensions · from £23,000
- Extension plans and drawings · from £1,550
- Glass box extensions · from £39,000
- Bungalow extensions · from £34,000
- Conservatory replacement extensions · from £26,000
- Double-storey extensions · from £49,000
- Single-storey rear extensions · from £27,000
- Home office extensions · from £20,500
- Kitchen extensions · from £35,000
- Pitched roof extensions · from £28,500
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
The price is fixed in writing once the design is settled, with a clear programme and payment stages.
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 New Cross
How much does an extension cost in New Cross?
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.
Can I get a price before anyone visits?
Yes. This page shows guide prices adjusted for New Cross, and the guide-price tool gives a range for your own size and finish in about a minute.
How long does an extension take in New Cross?
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.
Do you cover all of New Cross?
Yes, including the surrounding parts of Greater London. 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 New Cross
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.