The Warburg Institute is one of the world’s leading centres for the study of cultural history, with an open-stack library, archive and photographic collection at the heart of its work. Its Bloomsbury home, designed by Charles Holden in the 1950s, required extensive refurbishment to meet modern standards and to allow the Institute to grow its public-facing role. The project has delivered a comprehensive renewal of the existing building alongside a major new extension.
Our role was to provide structural and civil engineering design for both the refurbishment and the new-build elements. The most significant intervention was a two-storey courtyard extension, housing a lecture theatre and secure reading room. We developed an elegant exposed concrete frame solution that stands largely independently of the existing structure. Slender double-height columns, and a grillage of downstand beams support the lecture theatre roof, which incorporates a complex elliptical ring beam at its centre. This form referenced Aby Warburg’s own symbolic use of the ellipse and required intricate reinforcement detailing, with layers of small-diameter bars eased into shape on site to achieve the precise geometry.
We worked closely with specialist fabricators to develop CNC-cut formwork for the elliptical beam, coordinated reinforcement detailing with the concrete subcontractors, and trialled self-compacting mixes to achieve the high-quality as-struck finish. The result is a structure where the concrete itself becomes a defining architectural element.
Refurbishment of the original building brought with it further challenges, and was carried out in parallel with a refurbishment of the Slade School of Art on the top floor. We reconfigured the library stacks, reinstating Warburg’s original cataloguing system while improving natural light penetration and providing capacity for 20 years’ growth. We also worked with the design team to coordinate new MEP infrastructure within Holden’s original concrete frame and clay hollow pot floor slabs, supporting upgrades to the reading rooms, classrooms and public gallery spaces.
Two double-height lightwells were introduced between old and new, bringing natural light deep into the plan and offering visual connections into the Institute’s inner workings. The original utilitarian fire escape stair, serving both The Warburg and The Slade, was replaced with a more dynamic design with cantilevered landings which opened out the view into the courtyard.
Sustainability was central to the engineering approach. The concrete incorporated GGBS and recycled aggregates, reducing embodied carbon, while timber was sourced from FSC/PEFC-certified suppliers. The new extension is topped with a green roof, improving thermal performance and surface water management. Together, these measures support the University’s long-term environmental commitments while delivering a robust structure designed for longevity.
