A substantial fraction of Australian university buildings are naturally ventilated. These buildings consume a significant amount of energy and frequently suffer from overheating problems, resulting in poor indoor thermal comfort. This paper presents an investigation on the effectiveness of a range of energy conservation measures (ECMs) that can potentially be used to enhance energy performance and thermal comfort of these buildings. The ECMs considered in this study include information technology (IT) equipment and lighting upgrades, and measures focussed on occupant behaviour change. The effectiveness of each ECM was evaluated through modelling of a case study building at the University of Wollongong using the building energy simulation software DesignBuilder™. The thermal comfort of occupants was evaluated using the adaptive thermal comfort standards ASHRAE Standard 55 and EN15251. Results indicated that both adaptive thermal comfort standards can be useful in providing a clear picture of occupant comfort conditions. It was found that office IT equipment and lighting upgrades can potentially result in 50% savings in total office energy consumption, which in turn led to a reduction of up to 50% in overheating hours, compared to the base case condition. It was also found that 40% energy savings and a 50% reduction in overheating hours could be achieved through modelled occupant behaviour changes (i.e. turning off IT equipment and lighting as far as possible and night-purging in summer).