Single and double storey extensions in Belgravia. Trusted, professional, 30+ years' hands-on experience.
GS Renovation builds extensions on Belgravia properties, from the grand stucco townhouses to the compact mews houses tucked behind SW1's main terraces. Given how much of the area is listed or within a Westminster conservation area, every extension starts with the planning position. With over 30 years of experience, we manage groundworks, steel and fit-out as one project.

Extensions in Belgravia are rarely straightforward permitted development. Because so many townhouses are listed and the whole neighbourhood sits within Westminster conservation areas, permitted development rights are usually restricted or removed, and a full planning application to Westminster City Council is often needed. We assess your property's exact status early, so you know whether you are looking at permitted development, planning permission, or listed building consent before any design is finalised.
Where a rear or side-return extension is feasible, we prepare the design, foundations and structural scheme to satisfy both the council and building control. On listed properties we work sympathetically with the original fabric, and we coordinate the drawings, applications and party wall matters so the approval process is handled properly from the outset.
Belgravia's mews houses offer real potential for careful extension and remodelling, whether adding to the rear, reworking the roof or opening up the ground floor. These smaller SW1 properties often need steel beams to create the open living space owners want, all sized by a structural engineer and signed off by building control. We handle the groundworks, foundations and full fit-out under one team.
On the larger townhouses, rear extensions must respect the shared party walls, so we serve Party Wall Act notices before excavating or building against a neighbour's structure. From foundations and steelwork to roofing, plastering, electrics and the final decoration, we deliver a finished extension that suits the period character and the standards expected on a Belgravia address.
GS Renovation understands that a Belgravia extension is shaped as much by listing and conservation rules as by construction. We establish the planning position with Westminster City Council first, then deliver foundations, steel, roofing and fit-out as one accountable team. With 30+ years in SW1, you get a compliant, well-built extension and no surprises.
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
Every Belgravia project is priced on its own merits, as the cost of house extensions varies with the size, specification and condition of the home. We give a clear, itemised quote up front with no obligation. Call 07472 424 226 for an estimate tailored to your property. 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.
Most house extensions projects in Belgravia take between two and eight weeks depending on the scope and whether structural work is involved. We provide a clear programme before work begins so you know exactly what to expect.
GS Renovation knows Belgravia'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 Belgravia 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 Belgravia's homes are period, Georgian and listed properties, and we renovate them regularly. We plan each house extensions around their particular characteristics, such as conservation and listed-building rules, solid walls and original period features, so the result suits the building and meets building control.
It depends on the property. Because Belgravia is a Westminster conservation area with many listed buildings, permitted development rights are usually restricted or removed, so most extensions need a full planning application and often listed building consent too. We check your property's status with the council first, then design and build to whatever consent applies, alongside building control sign-off for the structure.
Absolutely. Our team works right across Belgravia and the SW1 area and neighbouring parts of Central London. Get in touch on 07472 424 226 to check coverage for your address.
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 Belgravia. 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 Belgravia and the surrounding areas. Explore a nearby location:
Contact GS Renovation today for a free, no-obligation quote for house extensions in Belgravia.
Get Your Free Quote