Indoor environment quality effects on occupant satisfaction and energy consumption: Empirical evidence from subtropical offices

Abstract

This study examines the impact of indoor environment quality (IEQ) on occupant satisfaction and energy consumption in Australia’s subtropical office buildings. First, Kano’s model was applied to 201 office occupants' satisfaction surveys to understand the influence of each IEQ parameter on overall occupant satisfaction. Then, a quantitative relationship between monitored IEQ parameters and energy consumption in three office buildings was developed during summer, winter and transitional months. Using Kano’s model, IEQ parameters were classified into Basic Factors, Performance Factors, and Bonus Factors based on their impact on occupants’ overall satisfaction. Basic Factors include ‘acoustic environment’, ‘lighting environment’, ‘level of privacy’, and’office cleanliness’, which were deemed a prerequisite for occupant satisfaction. As Performance Factors, ‘thermal environment’, ‘indoor air quality’, ‘furnishing’, ‘available space’ and ‘personal control’ had proportional relationships with overall satisfaction. The only identified Bonus Factor positively impacting overall occupant satisfaction was ‘View from the windows’. In subtropical climates, the relationship between IEQ parameters and energy consumption reveals that artificial lighting is the most energy-intensive IEQ parameter. The findings also suggest that Australian building experts may have over-emphasised the role that achieving thermal comfort plays in the energy consumption of office buildings in Australia’s temperate climates.