Performance gap in a multi-storey student accommodation complex built to Passivhaus standard

Although the Passivhaus design is rapidly spreading worldwide, limited studies have examined its actual performance during operation. This study used Australia's first student accommodation built to the Passivhaus standard as a case study to assess the gaps between design prediction and in situ performance. Passivhaus criteria, supplemented with the adaptive thermal comfort approach, were applied to evaluate the discrepancies between design predictions and measurements. This year-long study discovered significant gaps in three indicators, including primary energy renewable, overheating frequency, and space heating energy demand. The simulation was over-optimistic in the first two indicators but conservative in the last. The discrepancies were mainly caused by the default assumptions and inherent restrictions of the simulation platform. Improvements can be achieved by incorporating more advanced datasets for the estimation of appliance energy use, improving the feedback process from measurements to the simulation tool and developing a more integrated simulation package. The results of this study contribute toward a deeper understanding of the magnitude, causes, and solutions of performance gaps between design and operation stages for large Passivhaus projects.