What impedes stakeholders from implementing nearly zero-energy buildings in China? A multi-stage perspective based on transaction cost theory

Nearly Zero Energy Buildings (NZEB) are widely seen as a key pathway to achieving energy efficiency and decarbonization in the building sector. Although subsidies in some regions of China cover most explicit costs, large-scale adoption remains limited. The main reason lies in the significant hidden costs borne by stakeholders due to multi-stage certification systems, emerging technologies, and complex policies. Despite their impact, these costs are underexplored in current research. To address this, this study applies transaction cost theory and interviews 23 NZEB experts to identify hidden costs, then develops mitigation strategies validated by 12 experts and a focus group, yielding a three-tier roadmap. It makes three contributions: 1) It introduces a replicable “stage–stakeholder–cost” framework to analyze hidden costs in NZEB practices; 2) It identifies 36 transaction cost items and maps cost flows across 11 stakeholder groups, providing a model for visualizing procedural frictions in complex building environments; 3) It targets major transaction cost bottlenecks and, drawing on international experience, proposes and validates strategies to reduce hidden costs, offering a roadmap for China and other emerging markets.