The further expansion of the 1960s Grade I listed college designed by Danish architect, Arne Jacobsen, provides a student hall of residence and graduate centre at St Catherine’s College. The project adds to the initial expansion of student accommodation designed by Hodder + Partners in the 1990s. It features 78 additional student bedrooms within a cluster of three pavilions, and a three-storey cylindrical hub building providing a graduate common room and seminar space.
The new accommodation pavilion was designed to merge seamlessly with Hodder’s pavilions, with large external concrete fins cantilevering from the front elevation, precisely matching the existing scheme. The buildings were constructed in blockwork and precast concrete floors, with local in-situ concrete walls to support the external precast concrete fins. The detailing of the projecting precast brise soleil had to be redesigned to prevent cold bridging issues. We reduced the extent of insitu concrete works where possible, so that the construction programme could benefit from offsite production.
Contrasting with the accommodation buildings, the graduate centre is cylindrical in form, of reinforced concrete construction, with a lightweight steel lantern roof. The upper floor slab has a large circular cut out which allows natural light to be drawn in through the lantern clerestory windows to the upper two floors. The graduate centre structure utilises insitu reinforced concrete to form exposed and circular elements and mirrors the simple elegance of other college buildings.
The ‘green corridor’ that runs north to south across the site is an important element of the original Jacobson design. It had to be balanced carefully with the natural storm water storage requirements set by the flood risk analysis at the north end of the site and the archaeological importance of the central ditch, thought to be a civil war battlement. The corridor therefore played a key role in the positioning of the graduate centre building, and how it’s viewed from the south end of the site.
The site sits partially within a floodplain. Price & Myers undertook flood modelling to demonstrate the extent and level of future flooding, taking in to account the changing nature of the climate. The design required compensation measures to prevent flooding of the building and any increase in the local flood risk.
Site investigations identified ground contamination across the site which was mitigated by measures agreed in consultation with the Environment Agency. These included displacement piles to minimise disturbance of the underlying aquifers, and ground water monitoring through the piling operations.