Developing a life cycle assessment model for measuring sustainable performance of buildings in China

The construction industry contributes significantly to environmental pollution. The environmental problems caused by construction range from energy and resource consumption to waste emission throughout the building life cycle. With increasing attention being paid to building sustainability performance, numerous environmental assessment tools occurred. They have been developed and used to assist planning and design of sustainable buildings, and help improve overall environmental awareness and achieve the goal of sustainability in the construction industry. However, with critical reviews on the current tools, they are criticized as being ineffective and inefficient in addressing the building performance issues, as most of them only focus on assessing building performance on environmental criteria and the assessment does not take into consideration economic and social analysis. Sustainability is like a three-legged stool, with each leg representing areas of environment, economy and society. Any leg missing from the 'sustainability stool' will cause instability because the three components are intricately linked together. In addition, most current tools have not considered all the building phases in their assessment. As economic, social and environmental impacts associated with project development will vary at different stages throughout its life cycle, sustainable performance should be assessed and incorporated into the building process. Since the last century, China started to realize the importance of green buildings (CSUS 2012). A national SAT called Evaluation Standards for Green Buildings (ESGB) was launched in 2006 (Ye et al. 2013), and several international tools are adopted in China for assessing building performance. However, sustainable building assessment has significant regional differences and the application of international tools in China still have shortcomings. Moreover, the ESGB is also criticized for not sufficiently taking into consideration of economic and social issues in building life cycle assessment. In this research, different phases of a building life cycle are identified, as well as major activities for each phase in order to investigate how they influence the environmental, economic and social impacts. Both qualitative and quantitative methods are adopted in this research. Questionnaire survey and semi-structure interviews were used for data collection. The assessment indicators are generated by the data collection. An assessment model is established based on the results of data analysis and the literature review. It combines environmental, economic and social assessment to aid decision making. The assessment is integrated into the building life cycle, and the building performance on each stage is also indicated. The assessment details of each indicator are also discussed. The model is tested and verified by case study. Three projects are used as case studies. The sustainable performance of the three cases in every stage of the building life cycle as well as the overall performance will be analyzed. Quantitative methods and qualitative methods are used for assessing the indicators. The results using the developed model, the Building Sustainable Score (BSS), are also compared with the LEED and ESGB for deeper discussion. The value and innovation of this model are also discussed in this research.