Disaggregated I-O LCA model for building product chain energy quantification: A case from China

• We developed disaggregated I-O LCA models to calculate the product chain energy of buildings in China.
• The construction sector in Chinese I-O tables was disaggregated into fourteen sub-sectors.
• Aggregation in the construction sector causes a 15–225% overestimate for the product chain energy of buildings.
• Public buildings have high product chain energy due to intensive use of steel and concrete.
• Product chain energy of urban residential buildings is 2.9–3.3 GJ m−2, 87–94% higher than rural residential buildings.

Input–output life cycle assessment (I-O LCA) is a tool for calculating the product chain impacts of goods and services in an economic system. However, specificity and accuracy of model results is compromised by sectoral aggregation in I-O tables. Based on the 135- and 42-sector 2007 Chinese economic benchmark data, this study developed two disaggregated I-O LCA models for construction. The construction sector in Chinese I-O tables was disaggregated into fourteen sub-sectors, including thirteen building types and civil engineering projects. Results show that aggregation in the construction sector causes a 15–225% overestimate for the product chain energy of buildings. The disaggregated 148-sector I-O model yields results that are 10–14% higher than the 55-sector model. Public buildings such as cultural, sports and entertainment, research, and hotel and restaurant, have high product chain energy due to intensive use of steel and concrete. The product chain energy of urban residential buildings is similar, and ranges from 2.9 to 3.3 GJ m−2. However, this is 87–94% higher than rural residential buildings, which in China are primarily low-rise structures. This study enhanced the capacity of I-O LCA models for calculating the product chain energy of different building types in China.