Side return extensions in Becontree
If you live in Becontree and want more space without moving, a side return extension is one of the most practical ways to get it. We handle the drawings, approvals and the build.
- Guide price in BecontreeFrom £23,000 inc VAT
- PlanningOften permitted development; party wall notice usual
- Build time10–14 weeks on site
- Postcode districtsE20, IG3, RM6, RM8, RM9

Who a side return extension suits
- Narrow galley kitchens
- Homes where the garden is too small to lose much depth
- Victorian and Edwardian terraces with a rear outrigger
Will the council need to approve it?
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.
Homes in conservation areas, national parks, National Landscapes (formerly AONBs), the Broads and World Heritage Sites have tighter rules, so we always check the property's status and planning history before design starts.
Building over or within 3 m of a public sewer needs the water company's consent, usually through a build-over agreement, before the foundations go in.
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 should I budget for a side return extension in Becontree?
Prices below are for Becontree, using the London factor of ×1.3. They are guide ranges including VAT for the build only, not a quote.
Typical rates in Becontree: £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 |
Want a range for your exact size? The guide-price tool takes about a minute.
Extensions in and around Becontree
We cover Becontree and the postcode districts E20, IG3, RM6, RM8, RM9, RM10. Neighbouring towns we cover include Dagenham (2 miles), Barking (2 miles), Ilford (2 miles), Romford (3 miles).
For homes towards Essex, South Ockendon is around 7 miles away. 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.
From first visit to completion
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 draw the design, agree it with you and handle planning or permitted development checks and building regulations.
Fixed written price
You receive a written, itemised price and programme. Nothing starts until you are happy with it.
Build and sign-off
We build it with one project manager, book the building control inspections and hand over the completion certificate.
Side return extension questions answered
Who do I contract with for a side return extension in Becontree?
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.
Will my neighbours in Becontree 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.
How long does a side return extension take to build in Becontree?
On site, typically 10 to 14 weeks once approvals are in place. Before that, allow 6–12 weeks design and approvals.
How much does a side return extension cost?
Our guide range is about £2,730 to £4,940 per m² including VAT, so a typical 2 m × 5.5 m infill lands around £34,000 to £43,000 at standard spec in Becontree, more in London.
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 Becontree
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.