Delivering sustainable, high-performance buildings: Influence of project delivery methods on integration and project outcomes

The demand for sustainable buildings in the United States has risen because of accelerated depletion of natural resources, rising energy costs and green house gas emissions, and increased awareness of indoor environmental quality. Recently, this demand expanded from including only low energy strategies and products in buildings to prioritizing maximum energy conservation and occupant well being. All of these characteristics represent aspects of sustainable, high-performance buildings. Project delivery methods - e.g., design-build (DB) and design-bid-build (DBB) - can affect the level of team integration, which has been reported by the industry to result in optimal project outcomes and better value to the owner. However, there is a gap in the literature to examine the relationships among these results. This research studied how project delivery methods influence an owner's ability to achieve its sustainability goals mediated through the level of integration achieved in the delivery process. The research involved 12 in-depth case studies. The results show that the level of integration in the delivery process affects final project outcomes, particularly sustainability goals. Although DB and construction management at risk (CMR) have better chances of facilitating integration, results show that DBB also has the potential to provide higher levels of integration if it informally involves the constructor in the earlier phases of the project. Design charrette, project team member's compatibility, and commitment to project sustainability goals were also found to be crucial in achieving team integration and overall project success.