Double-storey extensions across South Croydon
From the first sketch to final sign-off, we plan and build double-storey extensions in South Croydon and the surrounding Greater London area.
- Guide price in South CroydonFrom £49,000 inc VAT
- PlanningUsually a householder application
- Build time16–24 weeks on site
- Postcode districtsCR0, CR2, CR7, CR8, CR9

Local to South Croydon
Postcode districts we cover around South Croydon include CR0, CR2, CR7, CR8, CR9, SM6. Neighbouring towns we cover include Croydon (1 mile), Purley (2 miles), Wallington (3 miles), South Norwood (3 miles).
For homes towards Surrey, Caterham is around 6 miles away. Across London, terraced houses with narrow side returns and tight access are the norm, which shapes everything from party wall notices to how materials reach the back garden.
When a double-storey extension makes sense
- Growing families who need a bedroom as well as a bigger kitchen
- Homeowners who would otherwise consider moving
- Houses with enough distance to the rear or side boundary
Double-storey extension prices in South Croydon
Labour and material costs vary across the UK, so for South Croydon we use our London factor (×1.3). The ranges include VAT and exclude design, structural and council fees.
Typical rates in South Croydon: £2,020 to £3,900 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 3 m × 4 m, two floors 24 m² | £49,000 – £59,000 | £56,000 – £73,500 | £71,500 – £94,000 |
| 4 m × 4 m, two floors 32 m² | £64,000 – £77,000 | £74,500 – £98,000 | £95,500 – £125,000 |
| 4 m × 6 m, two floors 48 m² | £96,500 – £115,500 | £112,000 – £147,000 | £143,500 – £187,500 |
Try the guide-price tool to see a range for your own size and finish.
Will the council need to approve it?
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.
Before any drawing is finalised we check whether the house is listed, in a conservation area or subject to an Article 4 direction.
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.
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).
Our process, step by step
Site visits are free and there is no obligation. Where drawings are needed, the design stage is priced in writing before it starts.
Free site visit
First, a site visit: we look at the house, garden, access and drains and listen to what you need.
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
We confirm the build price in writing, based on the approved drawings and the finishes you have chosen.
Build and sign-off
Our team builds the extension, keeps you updated weekly and finishes with building control sign-off.
Common questions in South Croydon
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for South Croydon, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
How long does a double-storey extension take to build in South Croydon?
On site, typically 16 to 24 weeks once approvals are in place. Before that, allow 8–16 weeks design and approvals.
Who do I contract with for a double-storey extension in South Croydon?
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.
Is a two-storey extension cheaper per square metre?
Usually. Our guide range is about £2,020 to £3,900 per m² of new floor area including VAT, compared with £2,280 to £4,420 per m² for single-storey work, because the foundations and roof are shared across two floors.
Does a double-storey extension need planning permission?
Often, yes. In England a two-storey rear extension can be permitted development only if it projects no more than 3 m and sits at least 7 m from the rear boundary, with matching roof pitch and obscure side windows. Side extensions over one storey always need planning permission. We confirm the route at the survey.
Book a free site visit in South Croydon
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.