Comparative Environmental Value-Stream-Assessment of Off-Site and On-Site 3D Construction Printing Processes (2024-11)¶

Extensive research has been conducted to establish a comprehensive understanding of the environmental impact of prefabrication and traditional onsite construction methods. In the case of 3D printing, onsite construction involves the transportation and onsite installation of a huge 3D printing setup, while offsite 3D construction printing (3DCP) requires the movement of bulky printed components. Consequently, the comprehensive environmental impact assessment of offsite and onsite 3DCP from raw material supply to the final construction stage needs to be investigated. This study aims to investigate the impact of onsite and offsite 3DCP processes on the environment considering the raw material production, transportation, printing and assembly processes. Environmental value stream assessment based on life cycle analysis (LCA) has been performed to analyze the impact of different processes on ecosystem, natural resources and human health. The findings show that the onsite 3DCP offers 21%, 19.7% and 27.6% lesser impact in terms of global warming potential (GWP), terrestrial acidification and fossil resource scarcity, respectively, than offsite 3DCP. Raw materials production contributes significantly to human carcinogenic toxicity and mineral resource scarcity, while transportation activities have a significant contribution to fossil resource scarcity and global warming potential. Sensitivity analysis shows that the offsite 3DCP can be preferred for small-scale construction containing concrete materials less than 140 tonnes in terms of transportation. In this case, moving the entire printing setup can have a greater environmental impact than transporting small printed components.