Single and double storey extensions in Clerkenwell. Trusted, professional, 30+ years' hands-on experience.
GS Renovation builds extensions across Clerkenwell, working with the warehouse conversions and new-build riverside apartments that define this EC1 corner of Islington. Over 30-plus years we have learned that space here is won cleverly rather than easily, whether that means a rear addition to a period workshop or a considered reconfiguration within a leasehold shell.

Clerkenwell is not a borough of generous rear gardens, so extensions here take different forms to the classic side-return you see further into Islington. Where a converted workshop retains a yard or lightwell, a single-storey rear addition can transform a cramped ground floor. We handle the groundworks, foundations, steel beams and roof works, then the full fit-out, all sequenced so you keep as much of the building usable as possible.
Whether your project is permitted development or needs a full planning application to Islington Council depends entirely on the property. Many EC1 flats and conversions have permitted development rights removed or restricted by leasehold terms and local planning designations, so a change that would be automatic on a suburban house is not here. We assess your title and the council's position before committing to a route.
Building against or near a shared structure in Clerkenwell almost always brings the Party Wall Act into play. The dense EC1 street pattern means your extension or new opening frequently touches a wall held in common with the unit next door, so we serve the right notices and agree the schedule before excavation begins. Getting this settled early keeps neighbours onside and stops the programme stalling.
For flats within a warehouse conversion or a new-build block, structural change is limited by the lease. You will need the freeholder's licence to alter, and the managing agent will set conditions on working hours, access and protecting common parts. We coordinate that paperwork alongside the building control applications, and we detail the acoustic and fire separation that regulations demand between one Islington home and the next.
Extensions in Clerkenwell reward a builder who understands leasehold reality and tight EC1 plots, not just bricks and mortar. GS Renovation manages the planning or permitted development question, the party wall notices, the freeholder's licence and the full build under one roof, backed by 30+ years across Islington and the surrounding Angel and Old Street streets.
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
We price each Clerkenwell project individually, because the cost of house extensions depends on far more than floor area. After a free survey you receive a clear written breakdown with no hidden extras. Call 07472 424 226 or email info@gsrenovationltd.co.uk. 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.
We will give you an honest timescale for house extensions in Clerkenwell after surveying your home. Most projects run on a clear weekly programme, and we tell you up front about any lead times on materials or approvals.
With more than three decades of hands-on trade experience behind us, GS Renovation is a trusted choice for house extensions in Clerkenwell. You get one accountable team, transparent pricing, fully insured tradespeople and genuine aftercare on every project.
Many single-storey rear extensions in Clerkenwell 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 Clerkenwell's homes are warehouse-conversion and new-build properties, and we renovate them regularly. We plan each house extensions around their particular characteristics, such as concrete or steel frames, building-management rules and modern services, so the result suits the building and meets building control.
It depends on the property. Some Clerkenwell homes keep permitted development rights, but many EC1 flats, conversions and buildings within planning designations have those rights removed, so you would need a full application to Islington Council. Leasehold terms can restrict change further. We check your title and the council's position first, then handle whichever route applies alongside building regulations and party wall matters.
Yes. We work throughout Clerkenwell and the EC1 area, as well as the surrounding parts of North London. Contact us on 07472 424 226 to confirm we cover your street.
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 Clerkenwell. 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 Clerkenwell and the surrounding areas. Explore a nearby location:
Contact GS Renovation today for a free, no-obligation quote for house extensions in Clerkenwell.
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