Hoare Lea devises environmental strategy for new university building
Faced with a brief for the new Student Services Building at the University of Leeds that included the harmonisation of building and services to reduce energy usage and lower the carbon impact, Hoare Lea Consulting Engineers combined a range of measures. The 6-storey 6750 m2 building, designed by architects Farrell & Clark, will accommodate the student services ‘one stop shop’, Internet café, academic departments with open-plan and cellular office and teaching space, together with breakout areas, meeting rooms and conference rooms for the university’s senior management team. The site at the main entrance to the campus heavily influenced the building’s oblique triangular footprint. The varying shallow to deep-plan format presented a number of space planning challenges, which generated the deployment of a spine wall and central atrium. The north-south orientation of the main elevations presents diametrically opposed environmental issues. Dynamic modelling has enabled optimum application of passive-solar-shading techniques to the curved south façade and appropriate selection of mixed-mode ventilation and cooling technologies. The curved spine wall, raised access floor, exposed concrete soffit and central atrium further promote the discreet application of sustainable technologies to achieve a comfortable, quality environment with low capital and operating costs. The proposed HVAC systems include mixed-mode ventilation using natural ventilation, mechanical displacement ventilation, static-chilled-beam water cooling and limited direct-expansion cooling. Thermal demands will be met by waste heat from the university’s central CHP plant supplying steam to plate heat exchangers serving independent heating and hot-water systems. To minimise energy consumption, the BMS will provide the ability to zone the HVAC systems to react to varying occupancy patterns and solar gains on the opposed north-south façades. Lighting levels and operation will have supplementary control linked to daylight availability and PIR detectors to minimise the use of electrical energy. Diverse sub-metering is provided across all energy and utilities demands, enabling consumption to be monitored and targeted. Total construction cost is £11 million, with M&E services costing about £3 million — excluding fees fit-out and VAT.