The new initiatives and regulations towards nearly zero energy buildings forces designers to exploit the cooling potential of the climate to reduce the overheating occurrence and to improve thermal comfort indoors. Climate analysis is particularly useful at early design stages to support decision making towards cost-effective passive cooling solution e.g. ventilative cooling.

There is an expanding literature on the value of sustainability features in buildings (European Commission, 2013; World GBC, 2013; World GBC, 2014). While several publications focus on the price differentiation between buildings with sustainability credentials and buildings with no sustainability credentials (Eichholtz et al., 2010; etc.), others examine the costs and benefits of sustainability features individually referring to both monetary and intangible values (Heerwagen, 2000).

The role of ventilation in achieving acceptable indoor air quality is examined in the light of emerging challenges, alternative mitigation strategies and performance indices within the spatial and time matrix of the indoor environment. By considering the source of contaminants, their nature, transportation mechanism and participation in source-sink relationships, several studies have shown that it may not be feasible nor adequate to rely on ventilation alone to attain the desired level of exposure, especially with respect to airborne aerosolised droplets with infectious potential.

This key note presents the objectives, approaches and expected results of the on-going annexes relevant for ventilation and air infiltration in buildings and illustrate the importance of and expectations to an increased cross-annex coordination and cooperation.

In the definition of the nZEB, the use of only one requirement is misleading. Different requirements are combined to a coherent assessment of an nZEB and to fit the definition given by the EPBD (2010/31 /EU) in article 2. In this presentation, we focus on the first requirement reflecting the performance of the building envelope characterised by the energy needs for heating and cooling.

The current regulation in Spain regarding Indoor Air Quality (IAQ) provisions is Building Code (Código Técnico de la Edificación) for dwellings and Regulations on Building Heating Installations (Reglamento de las Instalaciones Térmicas en los Edificios. RITE) for other kind of buildings.

According to past researches, most people spend 80%-90% of their time indoors. The ventilation is very important to people’s health and the comfortable surroundings around us. From the viewpoint of energy saving, mechanical ventilation will consume a large amount of additional energy. So variety of ways measuring natural ventilation is worth considering. In fact, in real life, many people tend to have their windows shut rather than open, and the reasons are complex.

The quality of indoor environments influences satisfaction, health, and work performance of occupants. Additional understanding of the theoretical and practical value of individual indoor parameters in relation to health and performance aids indoor climate designers to obtain desired outcomes. This also results in expenditure savings and increased revenue as well as health care and improved productivity. This paper reports on two experiments that investigated how heat, cooling strategy and background noise influence performance in a full-scale classroom mockup setting.