University of Sheffield Heartspace

The University of Sheffield’s Heartspace embodies the realization of a true urban transformation – a neglected, utilitarian courtyard has been transformed into a quadruple-height atrium under a striking roof. Beyond the physical transformation, a formerly passive, empty space has been transformed into a thriving, state-of-the-art center for learning and research. ... The ambitious project brings together two of the University of Sheffield’s most historic buildings that were separate and under-utilized (the Grade II listed Frederick Mappin Building and the 1885 Central Wing). The result is a remarkable space that solves a fundamental problem of disconnectedness. The outdated and fragmented facilities have been a barrier to collaboration between departments and the student experience. Now, two historically significant buildings are sympathetically merged to house new laboratories, offices and social spaces. The precisely constructed 1,400m² undulating atrium roof makes the new combined building a striking feature on the skyline of Sheffield, a city renowned worldwide for its engineering expertise. Fittingly, Heartspace is home to the Faculty of Engineering, whose students can now be inspired daily by the innovative architecture above them. The engineering teams worked intensively together to formulate a strategy for supporting the new roof that made it structurally independent of the existing historic structures and avoided overloading them, so that the historic integrity of the project was neither damaged nor overshadowed. The preservation and appreciation of the existing cultural heritage was a key element of the design vision. The roof is supported vertically by a series of ‘tree columns’ that characterize the atrium space. The connections between the trees and branches are strategically positioned to frame the existing classical elements and not obscure the historic details of the existing facades. The trees are constructed from tapering triangular sections that delicately reflect the ‘Star of David’ vents that are a recurring motif on the historic building facades. This also provides a sharp aesthetic that avoids the unsightly welded joints present in traditional CHS-derived tree designs, and allows for a unique tapered form in an economical and elegant manner. The newly constructed concrete courtyard apartment blocks continue this clean aesthetic, using the visually lighter slab edges tapering to 150mm to create thin, exposed structural planes for each of the two glass-wrapped blocks. Constructing the 1,370m² double curved roof on a limited listed site close to the city center was a daunting challenge, requiring imaginative logistical techniques and early consideration of crane strategies and plant access. In-depth studies were carried out on the optimal size of the glass panes and the relationship between number of pieces, element spacing and glass thickness were investigated, which enabled the holistic design to be optimized. The result was a refined, lighter steel frame that facilitates assembly. Roof slope and edge angle analyses were performed to understand the structural engineering aspects of the structural steel nodes and glass-to-glass interfaces to address drainage issues and determine the maintenance access strategy. The roof was designed as a prefabricated ladder to reduce the number of parts on site and minimize on-site welding. The tree supports were designed to be freestanding during installation to further reduce the number of temporary works. The steel diagram is connected via machined nodes that were designed in 3D and laser cut from thick plates. Laser cutting allowed for a smooth radius transition between the steel elements while being cost effective and easy to construct. In line with Waagner Biro’s sustainability approach, the structure was optimized. This allowed the weight of the steel structure to be reduced, resulting in a reduction in embodied carbon, transportation weight and the number of trucks required to transport materials to site. It is estimated that this optimization alone saved over 53,600 kg of CO2 emissions.