An integrated system dynamics-AHP-TOPSIS framework for green innovation in sustainable building materials: Application to a rapidly urbanizing economy

• Develops an integrated System Dynamics-AHP-TOPSIS framework for sustainability assessment of building materials. • Simulates 50-year lifecycle interactions among environmental, economic, and social indicators. • Identifies Compressed Earth Block, Structural Bamboo, and Green Roof systems as top-performing alternatives. • Provides a transparent and adaptable decision-support tool for sustainable material selection in construction. • Supports circular-economy principles and contributes to SDGs 9, 11, 12, and 13. The construction sector significantly contributes to some of the most pressing global challenges, including climate change, resource depletion, and environmental degradation, through intensive resource consumption and waste generation. A key pathway to mitigate these impacts is the substitution of conventional materials with sustainable and natural alternatives, whose performance must be evaluated not only technically but also across environmental, economic, and social dimensions of sustainability. This study develops an integrated System Dynamics-AHP-TOPSIS framework to assess the long-term sustainability of building materials used in walls, roofs, and structural frames over a 50-year lifecycle. The model simulates dynamic interactions among five key indicators: life-cycle cost (LCC), health and safety, recyclable material potential, landfill waste, and total waste generation. Expert-derived Analytic Hierarchy Process (AHP) weights were applied in TOPSIS to rank materials across wall, roof, and frame systems. Using Saudi Arabia as a representative case of rapid urbanization and resource intensity, the analysis produced normalized sustainability scores ranging from 0 to 1, where higher values indicate stronger alignment with the ideal sustainability profile. The results reveal that natural and renewable materials consistently achieved the highest sustainability rankings. The top performers in each category were: Compressed Earth Block (0.83) for wall systems, Green Roof (0.59) for roof systems, and Structural Bamboo (0.68) for frame systems. Conventional materials such as autoclaved aerated concrete, structural steel, and insulated panels scored lower due to higher costs, greater waste generation, and limited recyclability. The proposed framework provides a dynamic, transparent, and adaptable decision-support tool aligned with circular-economy principles and the UN Sustainable Development Goals (SDGs 9, 11, 12, and 13).