The construction industry is a major contributor to global carbon emissions, making the decarbonization of its supply chain a critical goal for sustainable development. This study aims to identify key drivers of decarbonization within the construction supply chain and analyze their interrelationships using causal and structural modeling techniques. A bibliometric analysis is conducted to highlight theoretical gaps in the field, followed by the application of the Fuzzy Decision-Making Trial and Evaluation Laboratory (Fuzzy-DEMATEL) method to identify key decarbonization factors, and the Adversarial Interpretive Structural Modeling (AISM) method to construct a causal model that reveals their interactions. The results identify 17 key factors, categorized into five levels, with low-carbon policy guidance and consumer preferences emerging as the most influential. Based on these findings, a three-tier strategy is proposed to guide decarbonization efforts within the construction supply chain. This research provides theoretical insights into decarbonization and offers actionable recommendations for future industry practices and policy development.

Under China’s dual-carbon strategy, the construction sector still lacks a systematic quantitative view of what drives its shift to a circular economy. This study couples the Decision-Making Trial and Evaluation Laboratory (DEMATEL) with Total Adversarial Interpretive Structural Modeling (TAISM) to build a weighted, multi-layer model of the policy–market–organization–technology chain. DEMATEL measures causal strengths, and TAISM arranges the variables into five levels without subjective thresholds, revealing a five-stage activation pathway. Fiscal incentives and regulations start the cascade; market demand amplifies their effect into a “resonant resilience” mechanism that improves cost performance. Robustness tests show 87% hierarchy stability and causal variation within ±0.6%. Sensitivity checks indicate that policy support must supply at least 30% of total network weight, because market capital alone cannot meet circular-construction costs. A three-tier intervention—policy incentives, financial amplification, and digital decomposition via green finance, BIM, and material passports—is therefore recommended.