Performance indicators

The increasing severity and duration of climate change is that extremes – notably heatwaves, increases the risk of human thermal stress in indoor environments where people spend most of their times. Recent field measurements have demonstrated significant overheating in the EU building stock in the EU, characterized by well-insulated and air-tight envelopes. This exposes vulnerable communities to increases mortality risks that is bound to only get worse with an ever-worsening climate warming.

Smart ventilation in residential buildings has gained rising attention recently for the benefits of reducing energy consumption and improving indoor environmental quality. This paper presents a review of the smart ventilation in residential buildings papers published from January 2017 to August 2023, as a continuation of (Guyot, Sherman, and Walker 2018) who reviewed the publications in this area up to 2016. A systematic approach was used following the PRISMA protocol.

Night-time ventilation is a natural cooling technology, in which cold ambient air is used to cool indoor spaces. This literature review analyses how recent studies have defined the effectiveness or efficiency of night-time ventilation. Most studies used the similar indicators related to heat removal, energy saving, cooling demand reduction, and thermal comfort. However, there were significant differences between the definitions of performance of night-time ventilation, both in terms of criteria of judgement and methods of analysis.

The lack of indicators assessing ventilative cooling effectiveness in a way to compare it with active cooling technics, makes its acceptance more difficult. Practitioners, norms, standards and guidelines are used to design and evaluate cooling systems in terms of Cooling Power (CP) or Seasonal Energy Efficiency Ratio (SEER). What could be the CP of a passive technique based on a day to night offset of the cooling process? What could be the SEER of mechanical night ventilation for summer cooling?

Residential ventilation standards, especially in Europe are slowly but substantially moving away from their usual prescriptive approach towards performance based specifications. While academics and policy makers argue about the relevant IAQ indicators, housing developers and end users need to make a choice between the different ventilation system options they are faced with in the market. Although several IAQ rating systems have emerged, a comprehensive assessment method to rate the inherent qualities of the ventilation system itself is not available [6].