Assessment of embodied carbon emissions for building construction in China: Comparative case studies using alternative methods

In China, the rapid development of the economy has currently led to the extensive construction work. Therefore, determining the carbon emissions embodied in building construction could contribute to successfully implementing the national policy of reducing greenhouse gas emissions. Accordingly, the purpose of this study is to provide a broad perspective on the carbon footprint of building construction. A comparative study was done on two alternative technics, namely, the process-based and the input-output analytical methods. The primary aim of this comparative study was to enhance the accuracy and detail of the data on the embodied carbon in building construction. Three buildings of differing heights and applications were assessed in the case study. The results indicated that materials manufacturing account for 80–90% of the total building embodied emissions. The main structure and the foundation work of the buildings were the sub-projects that contribute the most to embodied emissions (>60%). As both the process-level and the input-output methods have advantages and limitations, a hybrid approach was proposed that combines the advantages of the two methods. The results of this study could be helpful in the assessment and reduction of the embodied carbon typically associated with buildings.