Unlocking circularity in construction: a cradle-to-cradle assessment of prefabrication vs conventional methods of construction

Purpose The study aims to advance building-level sustainability assessment by employing a cradle-to-cradle framework incorporating closed-loop material flows. It evaluates the environmental and economic performance of prefabricated steel structures (PSS) compared to reinforced cement concrete (RCC) and load-bearing (LB) masonry structures, using extended system boundaries, thereby addressing the literature gap regarding the limited exploration of cradle-to-cradle assessment. Additionally, the study develops a comprehensive understanding of critical lifecycle phases, including end-of-life considerations, for informed decision-making. Design/methodology/approach The study employs an evaluation matrix comprising life cycle assessment (LCA) and life cycle cost analysis (LCCA), supported by inventory analysis, to quantify and compare resource usage, environmental impacts and life cycle costs of selected construction methods within a cradle-to-cradle system boundary. The assessment is structural-system-dominant, excluding identical non-structural and MEP elements. Uncertainty and sensitivity analyses are further incorporated to assess the influence of input parameter uncertainty, end-of-life allocation methods, degree of prefabrication and expected service life on overall performance. Findings Results showed extending the system boundary from cradle-to-operation to cradle-to-cradle altered the relative performance ranking of construction methods, highlighting the need to explicitly account for complete end-of-life stages and circularity potential to enable accurate sustainability assessment. For the case studies, LB emerged as the most preferred option (suitable for low-rise structures), followed by PSS and RCC (suitable for mid/high-rise building typologies). Originality/value The study presents a novel cradle-to-cradle, building-level assessment of PSS in comparison to RCC and LB masonry structures. It underscores the importance of incorporating closed-loop material flows and end-of-life processes in evaluation for accurate and comprehensive assessment of environmental and economic performance. It further reveals environmental and financial implications of selected construction methods across life-cycle stages, aiding sustainability-oriented decision-making.