Single and double storey extensions in St John's Wood. Trusted, professional, 30+ years' hands-on experience.
GS Renovation designs and builds extensions across St John's Wood, working on the bay-fronted Victorian and Edwardian terraces of NW8 as well as the larger detached villas near Hyde Park. With over 30 years of Westminster experience, we take a rear, side-return or wrap-around extension from foundations and steel through to the finished, fitted-out room.

The classic project on a St John's Wood terrace fills in the side return, that narrow strip beside the rear closet wing, to widen a cramped kitchen into a proper family space. We dig and pour foundations to suit the ground and any nearby trees, then install a steel frame so the original rear wall can come out. A glazed roof or rooflights bring light deep into the plan where the terrace was previously dark.
Whether this needs planning permission depends on the property. Many single storey rear and side extensions fall under permitted development, but that right is often removed or restricted in parts of Westminster, and it does not apply where the home is listed or in a conservation area. We check the exact position with Westminster City Council before design, so you know early whether a full planning application is required or not.
On the wider plots around St John's Wood, including the detached and semi-detached villas, there is often room for a double storey rear extension that adds a kitchen-diner below and a bedroom or en-suite above. These carry more load, so the foundations and steel beams are sized accordingly by a structural engineer and signed off under building regulations by building control, which governs the structure regardless of the planning route.
Extensions on a terrace almost always involve the Party Wall etc. Act, because you build up to or along a shared boundary, so we serve the notices in good time. From groundworks to roofing, plastering, electrics and the final kitchen or bathroom fit-out, one team runs the programme, keeps the rest of the house liveable and coordinates every trade so the new space is finished, not just built to shell.
Homeowners in St John's Wood choose GS Renovation because we manage the whole extension, the planning check with Westminster, the party wall notices, the foundations, the steel and the fit-out, under one contract. With 30+ years across NW8, we give honest advice on what your plot and its conservation status will allow, and finish to a standard that suits the area.
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
There is no fixed price for house extensions in St John's Wood, because so much depends on your property and what you want to achieve. We survey first, then provide a transparent written quotation. Contact GS Renovation on 07472 424 226 for a free 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.
Timescales for house extensions in St John's Wood vary with the size and complexity of the job. After our survey we give you a realistic schedule and keep you updated at every stage of the project.
GS Renovation knows St John's Wood's homes and how to renovate them properly. We handle the structure, the services and the finishes, deal with building control for you, and leave you with work that is certified, guaranteed and built to last.
Many single-storey rear extensions in St John's Wood 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 St John's Wood'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.
It depends on the property. Some single storey rear and side-return extensions in NW8 are permitted development, but Westminster often restricts those rights, and they do not apply to listed buildings or homes in a conservation area, both common in St John's Wood. We check your address with Westminster City Council first. Either way, the structure itself needs building regulations approval and building control sign-off.
Yes, St John's Wood is one of our core areas. We work on every street and the NW8 area and across the wider Central 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 St John's Wood. 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 St John's Wood and the surrounding areas. Explore a nearby location:
Contact GS Renovation today for a free, no-obligation quote for house extensions in St John's Wood.
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