CASE STUDY ASHRAE set a challenging budget and timetable for the renovation of its new headquarters building | ASHRAE HQ ZERO PRESSURE Turning a leaky old office building into an exemplar net-zero headquarters for a high-profile organisation is always challenging but even more so when that organisation is ASHRAE. Andy Pearson explains the approach Integral took to deliver for its knowledgeable client W e knew the Integral team and architects were going to have to be on their A-game, because we had a very educated client, says Stanton Stafford, principal of Integral Group. He is talking about the renovation of a 6,000m2 office building in Atlanta, Georgia, USA. The task was to turn this energy-consuming, 1970s building into a net zero energy, global headquarters fit for its client ASHRAE, CIBSEs transatlantic sister organisation. In addition to net zero energy consumption, ASHRAE wanted its new HQ to exceed the provisions of its own indoor air quality standards and to deliver a maximum demandside energy use intensity (EUI) of 67.5kWhm-2 per year (21.4kBtuft-2 per year), a figure consistent with the societys Advanced Energy Design Guide for zero energy office buildings. ASHRAE set a challenging construction budget of $8.57m (6.3m) for the works and an even more challenging completion date of October 2020, 18 months after it purchased the building. Our goal was to renovate this building to turn it into a high-performing, net zero-ready facility in a cost-effective method that can be replicated in industry, says Ginger Scoggins, chair of ASHRAEs committee responsible for commissioning the new headquarters. The building ASHRAE purchased was a typical out-of-town office, comprising two rectangular, three-storey blocks to the east and west of a glazed, barrel-vault atrium linking the two. A cast-in-situ concrete frame supports the building above a large basement, which includes plant space, and it was clad in alternate rows of precast concrete and glazing. Stafford, the projects mechanical engineer of record, says the design teams approach to delivering a net zero energy solution was based on the following guiding principles: n Use climate and place to inform the design by focusing on passive solutions n Use daylight as a primary lighting source to minimise reliance on electric light n Expand the width of the thermal comfort temperature band n Assess which mechanical systems are most appropriate to deliver comfort with the least amount of energy in use. 18 February 2021 www.cibsejournal.com CIBSE Feb21 pp18-21 Ashrae HQ.indd 18 22/01/2021 17:49