Leadership in Energy and Environmental Design for LEED Version 4 (LEED-EB v4) Gold Certification Strategies for Existing Buildings in the United States: A Case Study

Identifying factors that influence the choice of Leadership in Energy and Environmental Design (LEED) certification strategies for existing office building projects in the United States is a pressing issue requiring attention as it will help LEED professionals select the optimal certification strategy for each project. In this context, a quantitative research methodology with purposive sampling was used in this study to evaluate the impacts of project/building characteristics in LEED for Existing Buildings version 4 (LEED-EB v4) gold-certified projects in the U.S. LEED-EB v4 project/building characteristics include the project size and the number of buildings built before and after the 1973 energy crisis. LEED-EB-certified projects include a score for Location and Transportation credit (LTc1, “alternative transportation”) and scores for Energy and Atmosphere credits (EAcs) (EAc6, “renewable energy and carbon offsets”, and EAc8, “optimize energy performance”). From 112 LEED-EB v4 projects, the two following groups of projects with specific achievements were selected: Group 1 (n₁ = 13), which included high achievements in LTc1 and low achievements in EAc6 and EAc8, and Group 2 (n₂ = 13), which included high achievements in LTc1, EAc6, and EAc8. Exact Wilcoxon–Mann–Whitney and Fisher’s exact 2 × 2 tests were used to estimate significant differences between the two groups. The results of the selection of LEED-EB-certified projects in Groups 1 and 2 were that Group 2 outperformed Group 1 in EAc6 and EAc8 (p < 0.0001), while there was no significant difference between Groups 1 and 2 in LTc1 (p = 0.199). As a result, Group 1 outperformed Group 2 in LEED-EB v4 project size (p = 0.017). Group 2 outperformed Group 1 in the number of LEED-EB v4 gold-certified projects in buildings constructed after the 1973 US energy crisis (p = 0.005). It is concluded that, when choosing a LEED certification strategy for existing office buildings in the United States, LEED professionals should consider the 1973 energy crisis and the size of the LEED project.