Initial findings of a study commissioned by the Charles Pankow Foundation and Design-Build Institute of America show that integrated delivery methods,
Initial findings of a study commissioned by the Charles Pankow Foundation and Design-Build Institute of America show that integrated delivery methods, such as design-build and construction manager at risk, are superior in meeting or exceeding Leadership in Energy and Environmental Design (LEED) certification goals. Among procurement procedures impacting achieved sustainability level, qualifications-based selection was favored in the study results.
Released in October, Sustainable, High Performance Projects and Project Delivery Methods: A State of Practice Report is the first study addressing the impact of ÎgreenÌ building project delivery methods and procurement procedures on achievement of sustainable design and construction goals. It constitutes the initial phase of an ongoing study conducted by a team of researchers from the University of Colorado, University of Oklahoma, Pennsylvania State University, and Michigan State University. A full report of the first phase is available (as a pdf document) on the DBIA website.
Researchers evaluated the three most common delivery methods: 1) design-bid-build (DBB), i.e., an owner contracts separately for design and construction phases, often awarding construction contracts to the lowest bidder; 2) construction manager-at-risk (CMR), i.e., the owner contracts separately, but almost simultaneously, with a designer and a contractor, who provides construction management services as well as significant input during the design phase; and, 3) design-build (DB), a fully competitive project-delivery system that awards contracts for both design and construction to a single entity comprising one or several firms. Five procurement procedures sampled in the study included low bid, best value, competitive negotiation, qualifications-based selection, and sole source.
To determine the state of practice, researchers employed a three-tiered research approach encompassing industry survey, content analysis, and structured interviews. The industry survey elicited 230 responses from LEED Accredited Professionals (APs), addressing project delivery methods, procurement procedures, and certification level on specific LEED-certified projects. The content analysis was based on solicitation documents from 92 public and private projects representing over $2.2 billion in building investment. Structured interviews conducted with industry professionals and owners aided interpretation of results. Responses were elicited from 47 of 50 states and the District of Columbia.
While the study found that all project-delivery methods and all procurement procedures had been used to achieve each LEED certification level [certified, silver, gold, and platinum], some were more effective than others. Integrated delivery methods (DB, CMR) were used in 75 percent of LEED projects surveyed, and qualifications-based selection (QBS) was the most successful procurement procedure, according to ratings based on LEED AP evaluations and review of projects meeting or exceeding initial LEED rating goals.
Strong preferences among LEED APs for integrated delivery methods on LEED projects reflects their knowledge that the ability to integrate construction knowledge early in design is essential to maximizing sustainability. Integrated project delivery methods either eliminate price competition or include price as one of several factors that determine the contract award. Sustainable, High Performance Projects and Project Delivery Methods: A State of Practice Report provides insights for owners seeking to achieve specific sustainability goals.