In recent years, the construction industry has actively embraced circular economy principles in building design and construction, guided by standards like ISO 20887 and EN 15804+A1. This paper explores the integration of Life Cycle Assessment (LCA) and circular economy considerations in the design stage. Building Information Modelling (BIM) is employed to create and assess three building models: wood, concrete, and steel frames. LCA assessments are conducted following EN 15804+A1 and Building Circularity methods. The Best Worst DecisionMaking (BWM) method streamlines decision-making by analysing extensive LCA data to identify critical design factors. The findings underscore the significance of material selection, particularly in the often-neglected A1-A3 (product and transport stage) life cycle stages. Material choices significantly impact embodied carbon and Global Warming Potential (GWP) throughout a building’s life cycle. Reusability and recyclability of materials are crucial considerations in alignment with circular economy goals. BIM facilitates the analysis of material reusability and recyclability during design, offering practical insights. In complex LCA scenarios, BWM proves effective in guiding sustainable construction decisions, outperforming the TOPSIS method. Despite its potential, our literature review reveals that BWM remains underutilized in sustainable building decision-making. This study advances circular economy principles in building design, providing a robust foundation for informed and sustainable decisions. By combining BIM, LCA, and BWM, it underscores the construction industry’s commitment to reducing environmental impact and fostering long-term sustainability and Green Building Design.