Cost and Incentive Analysis of Green Building Label Upgrades in Taiwan’s Residential Sector: A Case Study of Silver to Gold EEWH Certification

In response to the global push for sustainable development, green building certification systems have become a key policy instrument for reducing carbon emissions in the construction sector. In Taiwan, the EEWH (Ecology, Energy Saving, Waste Reduction, and Health) system serves as the primary framework for evaluating building sustainability. However, while government incentives such as floor area ratio (FAR) bonuses aim to encourage adoption, private sector participation remains limited, especially in the residential sector. This study investigates the cost implications and incentive benefits of upgrading green building certification from the Silver level to the Gold level under the EEWH system, using eight collective housing projects in the Taipei metropolitan area as case studies. Through a detailed analysis of certification components, upgrade strategies, and construction cost estimates, this research quantifies the additional costs required for each sustainability indicator and evaluates the alignment between upgrade investments and incentive rewards. The findings reveal that the average cost increase associated with the Silver-to-Gold upgrade ranges between 1% and 3% of total construction costs, with certain design strategies offering high cost-effectiveness. Moreover, the study examines whether the current FAR bonus policy provides adequate motivation for developers to pursue higher certification levels. The results provide valuable insights for policymakers seeking to optimize incentive structures and for developers considering sustainable building investments.