Holistic LCA evaluation of the carbon footprint of prefabricated concrete stairs

Abstract

The construction industry accounts for a large proportion of the direct and indirect carbon emissions in China. The traditional cast-in-place method, still rather common, can no longer meet contemporary green buildings requirements. Prefabricated concrete components can reduce carbon footprint, especially the materialization stage that generates the bulk of the carbon emissions. A computational method to assess carbon footprint could inform emission reduction strategy. This study investigated prefabricated concrete (PC) stairs products and their carbon footprint at the materialization stage, divided into the production, transportation, and construction substages. Based on the life cycle assessment (LCA) method, the carbon emission calculation model was established and applied to compute carbon emissions of five representative case studies in Fuzhou City in China. The results indicated that: (1) the carbon emissions of PC stairs were mainly generated by raw-material consumption in the production stage; (2) the carbon emission intensity per unit height fluctuated around 811.40 kgCO2/m, per unit cost around 1670.89 kgCO2/10,000 Yuan, and per unit cubic quantity around 857.48 kgCO2/m3; and (3) A strong and significant linear relationship existed between total carbon emissions and three key attributes of project building height, cubic quantity of prefabricated stairs, and cost of prefabricated stairs. This study has developed a standard method to calculate the carbon footprint of a key prefabricated component in buildings. The findings have a reference value for assessing carbon emissions of other prefabricated components and developing sustainable strategies to reduce carbon emissions and energy consumption to align with green construction.