Parametric simulations to evaluate occupants' behavior incidence on building energy performance - A Passive House case study

The building industry's rising commitment to resource efficiency is influencing the evolution of building design and operation practices. At the same time, built environment decarbonisation is among the most important policy goals at the EU and global scale. High performance building design are emerging and their deployment in practice involves both new and existing buildings. Taking advantage of heat gains (solar and internal) to balance heat losses, as in passive design strategies, is becoming more increasingly relevant, but this must be carefully considered to reduce the risk of overheating during intermediate seasons and an increase of cooling demand during summer. In general, however, optimistic assumptions are frequently made during the design phase; semi-stationary calculation methods also are still widely used, especially for code compliance. Furthermore, the impact on performance of occupant's behaviour and comfort preferences is frequently overlooked. This study investigates the potential variability of simulated performance in a case study building constructed in Italy to the Passive House standard. The study contrasts the initial design hypothesis, which was developed using a semi-stationary model, to a larger set of data created through parametric simulations using a Design of Experiments methodology and a grey-box dynamic model. The modelling approach presented aims to detect potentially problematic assumptions early in the design process, with minimal computational effort. A detailed examination of design solutions from the early design stage can aid in the provision of more robust energy performance assessments, resulting in positive implications for techno-economic optimisation and for the credibility of high performance building design paradigms.