Energy impact of ventilation in building design - A literature review

The importance of building sector for the environmental concerns is pointed out by energy statistics: in OECD countries, buildings require approximately 40% of the total end energy use mainly for heating and cooling demand. Therefore, a huge amount of initiatives have been performed on a global scale in order to reduce energy consumptions in this sector by policy and technical measures. In Europe, the Energy Performance of Buildings Directive (EPBD) identified the fundamental areas of intervention for energy saving measures with a particular emphasis on the integration of passive strategies (natural lighting and ventilation, shading, thermal mass, etc.). The role of natural ventilation on the total energy savings in buildings becomes more relevant due to the higher thermal efficiency of the envelope and HVAC systems. According to the European guidelines, the minimum requirements and the potential of improvement for natural and mechanical ventilation has been expressed by the definition of new standards, introduction of the energy certifications and implementation of more efficient technologies. The adoption of these measures addresses the research sector and has a crucial impact on the design process for rewarding only selected solutions and for the emerging contrasts within the requirements of different standards involved for certification purposes. In this paper, a state-of-the-art on building ventilation is presented, mainly focusing on energy saving measures for residential and tertiary buildings. National standards, methods and technologies for the integration of natural, mechanical and hybrid ventilation have been analysed and compared. The influence of these measures for the future research needs is discussed.