A Multiscale Analysis of LEED-Certified Projects in Türkiye: Spatial Distribution and Istanbul Case Study

The LEED certification system, developed by the U.S. Green Building Council (USGBC) and globally recognized, is based on a sustainable approach to buildings. In this study, a multi-scale model was created to first quantitatively analyze—using descriptive statistics—the spatial distribution of LEED-certified projects in Türkiye across its seven geographical regions and 81 provinces. Subsequently, the relationship between the provincial spatial distribution of these projects and factors such as population and the level of socio-economic development was tested using Spearman's rank correlation analysis. Finally, Istanbul—the city with the highest concentration of LEED certifications—was selected for a detailed examination of LEED v4.1 projects. The study aims to reveal the spatial distribution of LEED-certified projects in Türkiye, determine the relationship of this distribution with population and socio-economic development levels, and assess the current status of LEED v4.1 projects in Istanbul. Methodologically, descriptive and inferential statistics were analyzed quantitatively using IBM SPSS Statistics Version 24 software. The findings indicate a total of 723 LEED-certified projects in Türkiye. It was observed that the distribution of LEED-certified projects lacks balance across regions and provinces; Istanbul leads by a wide margin, accounting for 63.35% of the total with 458 projects. A positive, strong, and statistically significant relationship was identified between the number of LEED-certified projects per province and both population size and the level of socio-economic development. Finally, an examination of 41 LEED v4.1 projects in Istanbul revealed that 29 fell under the "Operations and Maintenance: Existing Buildings" (O+M:EB) protocol, while the remaining 12 fell under the "Operations and Maintenance: Interiors" (O+M:Interiors) protocol. Regarding sustainability performance, it was found that 2 projects held Silver certification, 32 held Gold, and 7 held Platinum. It was also determined that the certification processes took approximately 356.54 days