AWARDS | BUILDING PERFORMANCE CHAMPION MIRVACS GOLD STANDARD Mirvacs 37-storey building towered over its rivals to win CIBSEs coveted Building Performance Champion Award. Andy Pearson examines the holistic approach to design to deliver both occupant comfort and energy outcomes T he walls of the 37-storey office building at 200 George Street in Sydney, Australia, look as if they are made from gold. Their appearance, however, comes from the hundreds of timber blinds comprising the buildings state-of-theart faade system. Known as the EY Centre, after its anchor tenant, the tower contrasts starkly with the grey, metallic, aluminium-and-glass faades of its neighbours. While its timber aesthetic sets it apart, however, what really differentiates the EY Centre is that it has established a new standard for how workplaces should be created. The 39,000m2 tower was developed and constructed by Mirvac, to an architectural design by Francis-Jones Morehen Thorp and an MEP scheme devised by Arup. At the time of the schemes development, in 2014, Mirvac had just launched its sustainability strategy, This Changes Everything. The development at 200 George Street was an awesome opportunity to walk the talk, says David Palin, Mirvacs sustainability manager, office and industrial. We set a target to be net positive in terms of carbon by 2030. For the first five years of the plan, we said wed reduce our carbon intensity by 20% and we wanted this project to achieve that as a minimum. It was a walk that was all the more significant after Mirvac decided to relocate its head office to six floors in the new building. The environmental performance benchmark for office buildings in Australia is the National Australian Built Environment Rating System (Nabers). Mirvacs sustainability targets were a 5-star Nabers energy rating and a 4-star Nabers water rating. It also set out to achieve a 6-star design rating and 6-star as-built rating under the Green Building Council of Australias (GBCA) Green Star scheme. The GBCA tools are a little more holistic, but they do use Nabers for their energy and water components, explains Palin. In developing the low-energy design, Mirvac took a whole-life approach by incorporating lessons it had learned from recent projects with the early involvement of its operations team in the design process. It was an exercise that resulted in the removal of a proposed tri-generation system and the blackwater (sewage) recycling plant, reducing development costs by approximately AUS$3m (1.66m). We view tri-gen as a liability, because if it goes offline your PROJECT TEAM Developer: Mirvac MEP engineer: Arup Architect: Francis-Jones Morehen Thorp Faade system: Permasteelisa Group 32 March 2019 www.cibsejournal.com CIBSE Mar19 pp32-34, 36 Mirvac v2.indd 32 22/02/2019 16:36