Appraising the effects of window opening behaviour in an office building in different climates

There is extensive pressure on sustainable buildings to deliver energy efficiency, but in practice, designs often fail to achieve the expected level of in-use energy consumption. One of the main factors behind this discrepancy between designed and real total energy use in buildings is the window opening behaviour. Towards nearly zero energy building (NZEB), building performance simulation is being increasingly deployed beyond the building design phase. With the aim to investigate how the climate affects the probabilistic model of window behaviour, the case study is simulated in different locations, i.e. Continental (Turin) and Mediterranean (Athens). Moreover, each simulated model refers to three comfort category heating and cooling set point conditions (Category I, II, III) as defined in Standard EN 15251:2006. Comparing the results, the influence of window behaviour on energy consumption in different climates generates energetically different outcomes. The present study highlights the importance of users’ interaction with window control systems in order to design sustainable and energy-efficient office buildings in a more realistic way.