The scheme provides six floors of workspace floors above a furniture showroom at ground and basement and includes an additional four storeys and new core.
The building has been substantially rebuilt and enlarged with a three-storey upwards extension to the rear and the addition of a set-back rooftop storey, finished in zinc with structural glass dormers.
The internal area has been increased by nearly a half from 706m2 to 943m2. A new lift, level entrance and reconfigured stair have been inserted to improve accessibility to all levels, with the new core carrying the primary loading of the additional four storeys. Combined with the lightweight construction used for new floors, roof and external walls, this has enabled the existing foundations, cast iron columns and masonry walls to carry the increased loading without modification.
To the rear of the building where it faces onto narrow Albemarle Way, the new façade’s articulated details are designed to echo those of adjacent Victorian buildings.
The emissions rate for all new build elements is 15 kgCO2/m²/year, a 34 per cent improvement on the Building Regulations requirement, giving an annual reduction of 3,000kgkgCO2.
In the retained parts, all sash windows have been replaced with triple glazing to provide better U-values and airtightness. New zoned heating systems and low-energy LED lights are specified throughout, with new showers and bike stores provided and, at roof level, an array of PV panels installed.
Architect’s view
Redeveloping this prominent Clerkenwell site required a surgical approach. Situated in a sensitive conservation area adjacent to a locally listed building, the project involved navigating a successful planning appeal while engineering a four-storey upward extension on a remarkably small footprint.
Our dual role as both architects and tenants during the design stage provided a unique advantage; we understood the building’s constraints through daily use, allowing for a highly interrogated design. This hands-on involvement continued through construction, with our practice remaining local to the site.
The project’s primary innovation lies in the blockwork core. To avoid invasive underpinning of the existing foundations under monolithic brick piers, we worked closely with the engineers to develop a new core designed to carry the primary loads of the four-storey extension while optimising the narrow floor plates for high-quality lettable area.
Architecturally, we chose to leave this structural solution exposed, referencing the historic character of Clerkenwell’s Victorian warehouses – a quality highly sought-after in converted buildings. By adapting traditional masonry techniques – specifically a shifted-scale Flemish bond using double headers – the blockwork becomes a decorative, textured feature and allows hollow blocks to be utilised to minimise material use and dead load. This approach successfully fuses modern structural necessity with an aesthetic that celebrates ‘as-built’ materiality, honouring the industrial heritage of its surroundings.
Ben Ridley, founder, Architecture for London
Project data
Location Clerkenwell, London
Completion 2025
Gross internal floor area 940m2
Form of contract JCT SBC
Construction cost Undisclosed
Architect Architecture for London
Client CRC
Structural engineer FORM Structural Design
M&E consultant Illuminous Consulting
QS Quantem
Fire engineer Marshall Fire
Project manager Stewart Watson
Approved building inspector Socotec
Main contractor Copper Projects (shell and core), Oktra (fit-out)
Environmental performance data
On-site energy generation 5%
Annual mains water consumption Not supplied
Airtightness at 50Pa Not supplied
Heating and hot water load 27 kWh/m2/yr
Operational energy 25 kWh/m2/yr
Total energy load Not supplied
Overall area-weighted U-value 0.4 W/m2 K
Predicted design life Not supplied
Embodied carbon Not supplied
Whole-life carbon Not supplied
Annual CO2 emissions 25 kgCO2eq/m2
Energy Performance Certificate rating A/B