Extension to Grade I-listed library, featuring a new single-storey basement beneath the provost’s garden. A connecting tunnel was excavated beneath the original structure’s historical walls.
RIBA South Award 2018
RIBA South Conservation Award 2018
Oxford Preservation Trust Award 2018
Founded in 1341, The Queen’s College is one of the University of Oxford’s constituent colleges. Its spectacular Grade I-listed library dates from 1692 and is one of the largest of any Oxford college, with a lending collection of 50,000 volumes and nearly 150,000 volumes in the historical collection. Requiring more room, and with surrounding space being limited, the only feasible place to accommodate an extension to the library was beneath the provost’s garden.
Eckersley O’Callaghan designed the structural scheme for this new basement. The basement sits in particularly sensitive surroundings, immediately adjacent to and below the existing library, with fragile historic walls on either side. We used a secant piled perimeter wall, propped during excavation to retain the surrounding ground and to minimise movements of the adjacent foundations.
Movement monitoring helped to control the process. The connection to the existing library was particularly complex, requiring careful underpinning to the old wall.
Key to the design was ensuring that the library’s valuable collection was protected, while at the same time accommodating the needs of its users. A rooflight running from north to south introduces natural light to the reading room, with the historic collection stored away from this light. Our structural glazing experience allowed us to provide key advice for the walk-on rooflight, and also for a glazed lift shaft.
The basement roof supports new planting to reinstate the existing provost’s garden, meaning the rooflight and access stairs are the only evidence of the basement.