Single and double storey extensions in New Cross. Trusted, professional, 30+ years' hands-on experience.
GS Renovation designs and builds extensions throughout New Cross, working with the bay-fronted Victorian and Edwardian terraces that shape the SE14 streets. With over 30 years across Lewisham, we take on rear, side-return and wrap-around projects, handling the groundworks, steelwork, roof and full fit-out so your enlarged home feels part of the original house.

The classic New Cross extension fills the side return, that narrow strip of open ground beside the original closet wing that so many SE14 terraces still have. Infilling it widens the kitchen dramatically and floods the plan with light through a glazed roof. We dig and pour foundations to suit the local ground, tie the new brickwork into the existing wall, and install the steel that lets us open the rear of the house right up.
A rear extension pushes the ground floor further into the garden, and a wrap-around combines both moves for a generous open-plan kitchen-diner. In terraces this close together the party wall almost always comes into play, so we serve notices on the neighbours early. We build the shell, fit the roof and glazing, then complete the plastering, flooring, electrics and decoration as a single continuous project.
Whether your New Cross extension needs planning permission depends on the property. Many single-storey rear and side-return projects fall under permitted development, which means no full application to Lewisham Council, though we still confirm the size limits and often obtain a lawful development certificate for certainty. Double-storey work, anything unusually large, or a home in a conservation area is more likely to need a full planning application.
Separate from planning, every extension must satisfy building regulations. Building control inspects the foundations, the steel beams, the insulation, the drainage and the structure as the job progresses. We keep planning and building control clearly apart, because they answer different questions, and we manage both with Lewisham Council on your behalf so nothing stalls halfway through your SE14 build.
GS Renovation gives New Cross homeowners one accountable team from foundations to final coat. We handle the structural engineering, the steel, the party wall notices with neighbouring terraces, and the building control inspections, while advising honestly on whether your project is permitted development or needs planning. Thirty years of Lewisham experience keeps your SE14 extension on programme and built to last.
George was brilliant. Lovely bloke, very reasonably priced and a perfectionist to boot. He completed our small kitchen renovation with care and great attention to detail. I've already recommended him to others.
Splendid job on our new kitchen refurb, including new flooring, moving the services, installing RSJ and preparing space for new back doors… George was always friendly, communicative and has an excellent attention to detail, ensuring everything is finished to a high standard.
Giorgio is an excellent and intelligent workman, and with very reasonable prices!… He paid a lot of attention to detail that is not common at all, and the final result was immaculate. Highly recommended!
FAQ
The cost of house extensions in New Cross depends on the size of the property, the specification and the scope of work. GS Renovation provides free, detailed and itemised quotations for every New Cross project. Call 07472 424 226 or email info@gsrenovationltd.co.uk for a no-obligation estimate. As a rough guide, house extensions in London typically starts from roughly £40,000 for a single-storey rear extension and rises with size and specification (indicative London ranges, MyBuilder and Checkatrade, 2026). Your figure depends on the size, specification and condition of the property, which is why we survey before quoting.
How long house extensions takes in New Cross depends on the size of the job, but we always agree a programme before starting and stick to it, keeping you informed from the first day to the last.
GS Renovation's team brings over 30 years of hands-on experience to house extensions and wider building work across New Cross and the surrounding area. We offer free quotes, a dedicated project manager, full insurance, building control compliance where required, and comprehensive aftercare.
Many single-storey rear extensions in New Cross fall under permitted development, but side returns, double-storey extensions and work in conservation areas usually need full planning permission. We assess your property and manage both the planning application and building control.
Yes. A large share of New Cross's homes are Victorian and Edwardian terraced properties, and we renovate them regularly. We plan each house extensions around their particular characteristics, such as solid brick walls, rear closet wings, side returns and original period features, so the result suits the building and meets building control.
Often it will not. Many single-storey side-return and rear extensions in SE14 qualify as permitted development, so no full application to Lewisham Council is required, though a conservation area, a larger footprint or a double storey may change that. Either way, the work still needs building regulations approval, and we confirm the correct route and manage the paperwork before we start on site.
Yes, New Cross is one of our core areas. We work on every street and the SE14 area and across the wider South East London, so wherever your home is, call 07472 424 226 and we will confirm we can help.
Every Service, One Team
The same trusted team, 30+ years' hands-on experience and free, no-obligation quotes apply to every GS Renovation service in New Cross. Explore what else we do locally:
Steel beam installation, RSJ and structural alterations.
Safe load-bearing wall removal with steel beam support.
Structural alterations, new openings and steel support.
Chimney breast removal with gallows bracket or beam support.
Open-plan kitchen, diner and living conversions.
Full refurbishments and whole-house renovations.
Bespoke kitchen design and installation.
Luxury bathroom and wet-room refurbishment.
Same Service, Nearby Areas
We carry out house extensions across New Cross and the surrounding areas. Explore a nearby location:
Contact GS Renovation today for a free, no-obligation quote for house extensions in New Cross.
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