Side return extensions across Greenwich
A side return extension in Greenwich starts with the right design and the right approval route. We take care of both, then build it with our own project management.
- Guide price in GreenwichFrom £23,000 inc VAT
- PlanningOften permitted development; party wall notice usual
- Build time10–14 weeks on site
- Postcode districtsSE3, SE4, SE8, SE10, SE13

Local to Greenwich
Across SE3, SE4, SE8, SE10, SE13, SE14, we can visit, measure and advise. We also work in nearby New Cross (1 mile), Blackheath (1 mile), Brockley (1 mile), Catford (2 miles).
For homes towards Kent, Swanley is around 10 miles away. 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.
Who a side return extension suits
- Homes where the garden is too small to lose much depth
- Victorian and Edwardian terraces with a rear outrigger
- Narrow galley kitchens
Planning rules that apply in Greenwich
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.
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.
Applications are decided by the local planning authority (your district, borough or unitary council).
Guide prices for Greenwich
Labour and material costs vary across the UK, so for Greenwich we use our London factor (×1.3). The ranges include VAT and exclude design, structural and council fees.
Typical rates in Greenwich: £2,730 to £4,940 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 1.8 m × 4.5 m 8 m² | £23,000 – £28,000 | £24,500 – £31,500 | £31,000 – £40,000 |
| 2 m × 5.5 m 11 m² | £30,000 – £36,000 | £34,000 – £43,000 | £42,500 – £54,500 |
| 2.2 m × 7 m 15 m² | £40,500 – £49,000 | £46,500 – £58,500 | £58,500 – £74,500 |
Try the guide-price tool to see a range for your own size and finish.
How the project works
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
We visit your Greenwich home, measure up, talk through what you want and check the planning position.
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
Our team builds the extension, keeps you updated weekly and finishes with building control sign-off.
Common questions in Greenwich
How long does a side return extension take to build in Greenwich?
On site, typically 10 to 14 weeks once approvals are in place. Before that, allow 6–12 weeks design and approvals.
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Greenwich, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
Will my neighbours in Greenwich be involved?
If a planning application or prior approval is needed, the council notifies neighbours. If the work is on or near a shared boundary, party wall notices may also be needed.
Will the kitchen be darker?
Not if the roof is designed well. A glazed roof or a line of rooflights along the boundary usually makes the room brighter than before.
Do side return extensions need planning permission?
In England many single-storey side returns fit within permitted development if they stay within the height limits and are no wider than half the width of the original house. Conservation areas, listed buildings and flats need an application. Other UK nations have their own rules, which we check.
Book a free site visit in Greenwich
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.