A multiple linear regression approach to correlate the Indoor Environmental Factors to the global comfort in a Zero-Energy building

The quality of the indoor environment, in terms of thermal, lighting, air and acoustic quality, grouped in the Indoor Environmental Quality (IEQ) concept, plays a key role in occupants' wellbeing and satisfaction. Only in recent years IEQ has been investigated as a whole. Today, IEQ occupies the same place of energy efficiency in the design of buildings, especially those with high performance level as the Zero-Energy Buildings (ZEB). The research deals with an experimental campaign during the cooling season carried out in a ZEB laboratory that involved 100 participants aimed at evaluating the IEQ and the indoor environments (e.g. thermal and air quality). The test consists in a survey, during which each participant is required to answer a questionnaire about how he feels the indoor environment. The experimental campaign was completed with a monitoring activity aimed at detecting the main environmental variables that can affect the participants' answers. Collected data were treated with regression techniques to highlight possible relationships between them. The results show how in a building with high levels of energy performances the air quality plays a key role on occupants' evaluation.