Typical commercial lease agreements in Australia stipulate 22.5 ± 1.5 °C in summer as the acceptable thermal condition that buildings have to meet, even though the overcooling incurs excessive and unnecessary energy use, gas emissions and financial expense. An argument that backs up this practice asserts that office workers' productivity and comfort will be jeopardised outside this temperature range. This paper investigated whether the office environments with a practical higher temperature setpoint can still be cognitively efficient and comfortable for office workers. In a controlled climate chamber, 26 office workers experienced the typical summer indoor temperature condition in Australia (22 °C) followed by the condition with a higher temperature setpoint (25 °C). In both conditions, subjects were required to fulfil Cambridge Brain Science (CBS) cognitive performance tests, NASA Task Load Index (NASA-TLX), and thermal comfort and air quality questionnaires. Meanwhile, participants' electroencephalogram (EEG) and heart rate (HR) were recorded under three different difficulty levels of Paced Auditory Serial Addition Tests (PASAT). Results showed that CBS test scores were not significantly affected by temperature; a higher temperature of 25 °C incurred a significantly reduced cognitive load for subjects, as has been observed by NASA-TLX, but probably due to the learning effect; the comparison between EEG and HR features during different temperatures did not show any significant difference. Participants' thermal comfort was not significantly jeopardized by the 3 °C temperature setback either. Results from this study favourably support a practical setback of temperature setpoints in Australian office buildings during summer

It has become increasingly important to study the urban heat island phenomenon due to the adverse effects on summertime cooling energy demand, air and water quality and most importantly, heat-related illness and mortality. The present article analyses the magnitude and the characteristics of the urban heat island in Sydney, Australia. Climatic data from six meteorological stations distributed around the greater Sydney region and covering a period of 10 years are used. It is found that both strong urban heat island (UHI) and oasis phenomena are developed. The average maximum magnitude of the phenomena may exceed 6 K. The intensity and the characteristics of the phenomena are strongly influenced by the synoptic weather conditions and in particular the development of the sea breeze and the westerly winds from the desert area. The magnitude of the urban heat island varies between 0 and 11°C, as a function of the prevailing weather conditions. The urban heat island mainly develops during the warm summer season while the oasis phenomenon is stronger during the winter and intermediate seasons. Using data from an extended network of stations the distribution of Cooling Degree Days in the greater Sydney area is calculated. It is found that because of the intense development of the UHI, Cooling Degree Days in Western Sydney are about three times higher than in the Eastern coastal zone. The present study will help us to better design and implement urban mitigation strategies to counterbalance the impact of the urban heat island in the city.

Activity-based working (ABW) provides office workers with a variety of indoor workspaces purposively designed to accommodate different tasks. Despite an increased use of ABW, studies focusing on its impact and the resultant office design are yet to follow suit. This paper addresses this knowledge gap by providing empirical evidence from studies conducted before and after relocation from contemporary open-plan offices to ABW spaces. Results from post-occupancy evaluation (POE) surveys (n = 896 responses), spot measurements of indoor environmental quality (IEQ) and step-count monitoring (one case study; n = 20 participants) before and after relocation are reported. A total of 10 workspaces participated (six combi and four ABW) in this study. Design features were documented and analyzed. While there were limited differences in the measured IEQ conditions between office layouts investigated here, ABW workspaces yielded significantly higher satisfaction results on key IEQ dimensions, perceived productivity and health. Office layout was also found as a significant (or nearly significant) predictor of occupants’ lightly active and sedentary time but did not affect occupants’ daily step counts and distance they travelled. These results highlight the significance and impact of office layout and human-centred approach to design on occupants’ satisfaction, perceived productivity and incidental physical activity opportunities.