Evaluating Decision Bias in Green Building Rating Systems: Evidence from Malaysia

The construction sector faces increasing pressure to demonstrate sustainability, with Green Building Rating Systems (GBRSs) increasingly functioning as decision-support tools that influence design prioritization, investment decisions, and certification outcomes. Sustainability in the built environment is commonly understood as the balanced consideration of environmental protection, economic viability, and social equity. However, limited empirical attention has been given to whether credit weighting structures in the rating systems reflect the balance in shaping sustainability decision priorities. This study examines whether GBRSs embed imbalanced decision logics that privilege specific sustainability dimensions over others. Using content analysis of technical manuals and normalized scoring of credit weightings, Malaysian GBRSs of Green Building Index (GBI), GreenRE, and MyCREST are compared with the international Leadership in Energy and Environmental Design (LEED) tool. Credit allocations are mapped across environmental, economic, and social pillars to examine their relative emphasis. The results reveal a pronounced environmental criteria dominance (61–85%), alongside modest attention to social aspects (11–28%) and minimal representation of economic considerations (0–5%). The findings indicate that current GBRSs embed implicit decision biases that systematically prioritize environmental performance while underrepresenting economic viability and social outcomes. By revealing how sustainability assessment frameworks structure decision priorities through credit weighting mechanisms, this study contributes to a more critical understanding of how GBRSs influence sustainability decision-making.