What level of design needs to be completed prior to advertising a Design-Build Contract?
While the level of completed design may affect the proposals, clearly defining the project’s scope is critical to the ultimate success of the project. The level of design included in a request for proposals (RFP) will depend on the size and complexity of the project, the degree to which performance specifications are used, and the owner’s desire to allow for design innovation while controlling scope. Both the clarity of the scope and the level of design impact the ability of the proposers to respond to the initial RFP, and the selected design-builder to develop a cost-effective and constructible project design in a timely and competent manner. While each project is unique, no more than 30 percent of preliminary design should be completed before DB contract award. Lower percentages are possible as the contracting agency gains more experience with DB, and as greater reliance is placed on performance-based specifications. Early value engineering and constructability reviews should be part
