Evaluation of Existing Green Office Buildings in European and Mediterranean Countries

One of the gaps in green building research in European and Mediterranean countries is the assessment of Leadership in Energy and Environmental Design (LEED)-certified projects in the context of the LEED rating system’s ongoing transition from a prescriptive to a performance-based approach. This study evaluates LEED certification strategies by analyzing the statistical association between five independent performance indicators and the overall LEED score for LEED for Existing Office Buildings version 4.1 (LEED-EB v4.1) gold-certified office projects in Sweden, Italy, Israel, Spain, Germany, and Ireland using simple linear regression. The results showed that each of the six above-mentioned countries demonstrated a unique LEED certification strategy for LEED-EB v4.1 gold-certified office projects. Linear regression revealed an unexpected result: the statistical association between the independent indicator (energy) and the dependent indicator (overall LEED) score was statistically insignificant (R² = 0.04 and p = 0.359; R² = 0.13 and p = 0.112, respectively) in LEED-EB v4.1 gold-certified office projects in Germany and Ireland. However, in Sweden, Italy, Israel, and Spain, this association was statistically significant (R² = 0.38, 0.46, 0.53, and 0.40 at p < 0.001 in all cases, respectively).