Leadership in Energy and Environmental Design for Existing Buildings Version 4.1 (LEED-EB v4.1) Gold-Certified Office Space Projects in European and Mediterranean Countries: A Pairwise Comparative Analysis

There is a gap in the research on LEED-certified projects that has arisen from combining the “old” LEED system and “new” LEED version in green building practice. This study is focused on gold-certified office projects under LEED for Existing Buildings version 4.1 (LEED-EB v4.1). Wilcoxon–Mann–Whitney and Cliff’s δ tests were used to conduct a pairwise comparison of six countries (Sweden, Ireland, Germany, Spain, Italy, and Israel) in terms of five performance indicators (transportation, water, energy, waste, and indoor environmental quality). The results show that Sweden and Germany outperformed Italy (p = 0.002 and 0.018, respectively) in transportation performance. Ireland outperformed Italy and Israel (p = 0.015 and 0.032, respectively), and Germany outperformed Italy and Israel (p = 0.003 and 0.009, respectively) in water performance. Germany outperformed Sweden, Ireland, and Israel (p < 0.001, respectively) and Sweden, Spain, and Italy outperformed Israel (p < 0.001, p = 0.008, and p = 0.009, respectively) in energy performance. Italy outperformed Sweden, Ireland, Germany, and Israel (0.001 < p ≤ 0.013) and Spain outperformed Germany and Israel (p = 0.015 and p < 0.001, respectively) in waste performance. Israel outperformed Sweden, Germany, and Italy (p < 0.001, p < 0.001, and p = 0.006, respectively) and Spain, Ireland, and Italy outperformed Sweden (p < 0.001, p = 0.002, and p = 0.004, respectively) in indoor environmental quality performance. The findings of this study show that each of the six selected countries has an individual LEED-EB v4.1 certification strategy. This study contributes new knowledge that can support LEED professionals in developing LEED certification strategies for each country.