This study analyses the effectiveness of Integrated Building Management Systems (iBMS) as an option to reduce Greenhouse Gas (GHG), such as carbon emissions and improving energy consumption in a hotel building within the busy urban areas of Sydney, Australia. In this research, a case study approach using quantitative data was employed to provide a comprehensive assessment. By time series analysis, 12-months worth of energy consumption data during pre- and post-implementation of iBMS in the selected hotel has been calculated and analysed using percentage reduction formula to identify whether there is a significant impact of implementing iBMS in reducing energy consumption. Although the system may require a considerable upfront costs, the overall benefits in a longer term fulfill its intended objectives. Since commissioning iBMS, the findings indicate a significant reduction in electricity and gas consumption, as well as carbon (GHG) emissions one year’s time, by around 16, 18 and 21 percent respectively, which is on track in comparison with similar studies in other regions.