Coupling energy and numerical analyses for evaluating possible ventilation strategies in a NZEB

The revised Energy Performance of Building Directive, introduced in 2018, has drawn major attention on indoor environmental quality, placing the need for optimizing occupants’ comfort and health at the core. Ventilation strategies can strongly influence the indoor conditions, thus asking for a careful study on the most profitable strategies since the design phase. Despite the benefits that a controlled mechanical ventilation could have on air quality and thermal comfort, in Mediterranean buildings the natural ventilation is still predominant. For this reason, the paper aims to compare the two ventilation strategies, based on a set of Key Performance Indicators, belonging to different dimensions (i.e. energy performance, thermal comfort, air quality) for a residential nearly-zero energy building in North-West of Italy. In order to better capture local comfort and air quality conditions, the traditional energy dynamic simulation is coupled with the CFD analyses, using DesignBuilder software.