Leadership in Energy and Environmental Design Commercial Interior Version 4 (LEED-CI v4) Gold-Certified Office Space Projects: A Pairwise Comparative Analysis between Three Mediterranean Countries

Abstract

Over the past five years, Leadership in Energy and Environmental Design Commercial Interior version 4 (LEED-CI v4)-certified office projects have been intensively studied in the USA and China, but they have not yet been studied in the Mediterranean region. The purpose of this study was to explore office building certification strategies for LEED-CI v4-certified projects in the Mediterranean region. The study design included pairwise comparative analyses between Spain (number of projects (n) n1 = 14), Türkiye (n2 = 13), and Israel (n3 = 11). Cliff’s δ and exact Wilcoxon–Mann–Whitney tests were used to process ordinal and discrete data, while the natural logarithm of the odds ratio and 2 × 2 Fisher’s exact tests were used to handle dichotomous data. It was found that Spain and Türkiye outperformed Israel in the Location and Transportation (LT) category due to their desire to reduce the use of private transport. Spain and Türkiye were ahead of Israel in the LTc5 “reduced parking footprint” credit (p = 0.008 and 0.0005, respectively). Israel outperformed Spain and Türkiye in the Energy and Atmosphere (EA) category due to the sum of all six EA credits (p = 0.086 and 0.010). Spain overtook Türkiye and Israel in the Materials and Resources (MRs) category due to Spain’s increased use of environmental product declarations. Spain and Türkiye were ahead of Israel in the following four MRs credits: MRc1 “long-term commitment” (p = 0.030), MRc2 “interiors life cycle impact reduction” (p = 0.037), MRc3 “building product disclosure and optimization—environmental product declarations” (p = 0.029), and MRc5 “building product disclosure and optimization—material ingredients” (p = 0.034). Spain, Türkiye, and Israel showed similarly low levels of achievement in the Indoor Environmental Quality (EQ) category (p ≥ 0.405). However, Spain and Türkiye outperformed Israel in the following two credits: EQc1 “enhanced indoor air quality strategies” and EQc2 “low-emitting materials” (p = 0.001 and 0.060, respectively). In parallel, Israel outperformed Türkiye in the EQc3 “construction indoor air quality management plan” (p = 0.026), and Israel outperformed Spain in the EQc8 “quality views” credit (p = 0.066). As a result, a pairwise comparison of the three Mediterranean countries showed that each country has a unique LEED certification strategy. Knowledge of the above green building strategies will be helpful for LEED professionals.