Development of an assessment methodology for IAQ ventilation performance in residential buildings: An investigation of relevant performance indicators

Abstract

Ventilation of residential buildings is an important area of research, since it addresses crucial issues: providing healthy indoor air to occupants, avoiding condensation risk and damage of the building, as well as ensuring energy efficiency. With regard to regulatory or labeling requirements, performance-based approaches for ventilation should be developed. These must ensure that a ventilation system is designed not only to save energy but also to avoid risks to occupants' health. In order to formulate a performance-based approach, a crucial question has to be addressed: What are the relevant indoor air quality (IAQ) performance indicators to be calculated? In this paper, we present an extensive investigation of the literature on IAQ performance in order to identify a reduced set of relevant indicators. We identified five relevant IAQ performance indicators to be used as output data: maximum cumulative exceeding carbon dioxide (CO2) exposure over 1000 ppm, maximum cumulative occupant formaldehyde (HCHO) and fine particulate matter (PM2.5) exposure, maximum percentage of time with relative humidity (RH) higher than 70% (condensation risk), and maximum percentage of time with RH outside a range of 30–70% (health risk). Importantly, we demonstrate that a performance-based method using these five IAQ indicators is relevant, applying it to a low-energy house.