CASE STUDY | LSBU HUB LSBUs cool hub More than half of all UK building services engineers studied at London South Bank University, so BDPs services retrofit of the main building on the campus had to demonstrate best practice in every function. BDPs Laura Smith reports on the steps taken to transform a tired teaching facility into the collegiate LSBU Hub B uilding services engineers who studied at London South Bank University (LSBU) may no longer recognise their old lecture halls, after an extensive refurbishment of the biggest academic building on the universitys Elephant and Castle campus. Making up 20% of the LSBUs teaching and learning space, the London Road building has been given an extensive, sustainable refurbishment and redesign, to increase the amount of flexible teaching and learning space in the heart of the university. Designed by architect Wilkinson Eyre, the LSBU Hub, as it is now known, was overseen by building services engineers, acousticians, lighting designers and sustainability consultants from BDP, who vastly improved the buildingss acoustics, lighting and thermal performance. LSBU has a long-standing connection with the built environment. More than half of the building services engineers in the UK studied there, including many of those working on the project, including three apprentices who worked on it while studying at the university. The existing building suffered from poor ventilation, and poor acoustic and thermal performance, which needed to be overhauled by BDP. The retained structure of deep concrete downstand beams posed several challenges for the project team, so careful coordination of services, and innovative solutions, were required. As well 32 April 2023 www.cibsejournal.com as ensuring the building is accessible and comfortable, the project team had to keep carbon emissions to a minimum. LSBU Hub has a wide range of functions. It is the new home of the Perry Library, which takes up most of the top two floors, while some new catering provision has been added through a grab-and-go caf and a refectory bar. Eight lecture theatres, fitness facilities, teaching rooms, informal learning spaces, and other catering amenities have been refurbished, and small cellular teaching spaces have been replaced with larger classrooms. Redefining the building use A feasibility study, undertaken in 2018, identified the negative impact on building users of the blank external faades, warren-like interiors, and poor accessibility. The university recognised the need to allow the building to work in a communal, cooperative and collaborative way, with larger open-plan spaces. The upgraded envelope achieved U values of between 0.2 and 0.35W m-2K-1 for the opaque elements, and 1.42 and 1.55W m-2K-1 for the glazed bays, and provided improved acoustic and thermal performance, including solar-glare control. Because of the central London location, the majority of spaces are sealed with demand-controlled mechanical ventilation (based on CO2 sensor readings). Displacement ventilation is installed in the double-height library spaces. On the quieter faades, there is natural ventilation, with occupancy control for the small LIGHTING STRATEGY The approach to the lighting design process was to complement the architecture with minimal intervention and ensure bright soffits, particularly in areas where daylight is low. The waffle slabs are exposed in many spaces and now form an integral part of the lighting strategy. A custom suspension luminaire was engineered by Zumtobel (Stratus) to project 100% indirect light to the slabs from a slim profile. This creates an enhanced perception of spaciousness and, through inter-reflection, provides the required illumination in the spaces where it is used. The lit effect is calm and blends well with daylight, with excellent light uniformity to walls, soffits and floors. Warm-white light was used throughout the library areas (with neutral white uplight) to enhance the extensive wood cladding and differentiate the space from other parts of the building. All luminaires are fully dimmable and controlled in response to occupancy and daylight.