House Extensions Becontree

GS Renovation builds extensions across Becontree, where the interwar terraces of the estate were planned with gardens behind them and small kitchens at the back. That garden space in RM8 is where most families grow, and with our founder's 30+ years on the tools, we take on the groundworks, the steel and the full fit-out as one project.

In Becontree, a single-storey rear extension typically starts from £40,000, or £2,000 to £2,800 per m² (indicative London ranges, Architecture for London, Resi, MyBuilder and Checkatrade, 2026). GS Renovation Ltd, a building contractor based in Potters Bar, does the work in Becontree: the structural engineer we appoint designs the structure, we build it, and building control signs it off.

Rear and side extensions on Becontree plots

Because most Becontree houses have their garden at the back, single storey rear extensions, and side extensions on end-of-terrace houses, are some of the most rewarding work we do in RM8. We dig and pour foundations sized to the ground conditions, build the walls and roof, and drop in a steel beam where the extension opens into the existing kitchen or reception to create a bright, open-plan space at the back of the house.

On an end-of-terrace house with land to the side, a wrap-around or two-storey extension can add a bedroom and en-suite above a larger kitchen-diner, subject to planning. We coordinate the structural engineer, the foundations, the drainage and the internal knock-through together, so the new and old parts of the interwar house work as one home rather than a bolt-on.

Housing in Becontree

Becontree has around 19,820 homes on the Council Tax list: 19% post-war, 80% interwar and 1% predate 1919, with 19% flats and 81% houses. Terraced houses make up 74% of homes here, and a rear extension on a terrace in Becontree digs foundations close to both neighbours, so notices to both are normal.

Sizing a Becontree rear extension against the two SPDs

Where a Becontree extension needs planning permission, two lines in the Residential Extensions and Alterations SPD shape it before any design work. A single storey rear extension to a terraced or semi-detached house should not normally exceed 3.65 metres deep from the original rear wall, and an extension should not normally cover more than 50% of your garden space. Because depth is measured from the original rear wall, an earlier addition at the back counts against it. Measure the garden before the kitchen layout is fixed, because on a short plot the garden test can limit the scheme before the depth one does.

On the estate a second document now sits alongside it. Barking and Dagenham Council's Cabinet adopted the Becontree Estate Supplementary Planning Document and Design Code on 16 June 2026, and because the Becontree Estate is a Non-Designated Heritage Asset, that SPD is a material consideration in any application within it. Drawings prepared before that date should be checked against it. For a rear extension, that means showing how its roof, materials and openings relate to your house as it was built, not only to the house next door, which may already have been altered.

Planning and party walls in Barking and Dagenham

An extension in Becontree may fall under permitted development, or it may need a full planning application to Barking and Dagenham Council, and which route applies depends on the size, height and position of what you want to build. We assess your specific house honestly at the survey stage and tell you clearly which path you are on before any drawings are commissioned.

Either way the build itself must meet building regulations, with inspections at foundation, structure and completion. Where a side extension runs up to the boundary or the works affect the shared party wall with a neighbouring RM8 house, the Party Wall Act applies, so you serve notices early as building owner, with the drawings we supply, and the whole project keeps moving.

Kitchen extensions in Becontree

91% of the houses in Becontree are terraced. On a terrace the kitchen extension is built out from the back, into the side return where the house has one or across the full rear width, and a steel beam takes the old back wall so the kitchen and the new room become one space. The fit-out is priced on its own page, kitchen renovation in Becontree; the build figures are in the table above.

Side return extensions in Becontree

Side returns belong to Victorian and Edwardian terraces, and only 1% of homes in Becontree predate 1919, so they are the exception here; most extensions run across the full rear width instead. Our side return extension page covers the build in detail, with build rates of £2,400 to £3,200 per m².

Double storey extensions in Becontree

Under permitted development a two-storey rear extension can go no more than 3 metres beyond the original rear wall and must stay at least 7 metres from the rear boundary, and in a conservation area it is not permitted development at all. Many gardens are too short for the 7 metre rule, so a double storey extension in Becontree often needs planning permission from Barking and Dagenham Council. On the 74% of homes that are terraced, the neighbours' windows usually decide the depth. A Barking and Dagenham Article 4 direction removes permitted development rights for porches for all properties across the Becontree Estate (council source). Our double storey extension page explains the build, at £1,800 to £2,600 per m² across both floors.

• Levels, drainage and landscaping made good around the new build
• Drainage diversion and build-over agreements with the water authority
• Single and double storey extensions

VOA Council Tax stock of properties, March 2025, for all 5 statistical areas in Becontree. Counts rounded by the VOA.

Once you know the scope of the house extensions in Becontree, it helps to read RSJ and steel beam installation in Becontree, house extensions across Barking and Dagenham, double storey extensions, party walls and extensions, house extensions anywhere in London and Garage Conversion Cost.

Why Becontree Homeowners Choose GS Renovation

Becontree owners choose GS Renovation because we build extensions end to end, from the first trial hole to the final coat of paint. We advise whether your project is permitted development or needs a planning application to the council, manage the steel and building control, and draw on our founder's 30+ years on the tools. One accountable team, no gaps between trades.

• Garden levels and access made good where the build meets outside
• Scaffolding and site set-up planned for tight terraced plots
• Paperwork and certificates handed over for when you sell

Checked by Abdelaaziz Saaid, founder and director of GS Renovation Ltd (Companies House no. 14611254). Structural design is by the consulting engineer appointed to your project.