Upstream Problem Solving Under Uncertainty and Ambiguity: Evidence From Airport Expansion Projects

Environmental changes are common during development of large engineering (infrastructure) projects. To accommodate them when they occur, developers design and physically execute the upstream base building with preliminary information about the downstream business-critical fit-out. Base-building subsystems provide service space for occupancy, whereas fit-out subsystems make the space functional. We build theory on design under uncertainty and ambiguity from case study research, drawing on theory of preliminary information exchange in concurrent development. We find that the base-building subsystem shows low sensitivity to incremental changes in fit-out. However, it shows high sensitivity to radical changes, unless the two subsystems interact in a modular fashion. In the face of slow resolution of downstream uncertainty and difficulties in decoupling the physical interfaces (as is the case in modular design for example), upstream developers avoid starvation by making working assumptions at risk and exploring the space of possible design solutions through an early “optioneering” stage. Two patterns for problem-solving upstream stand out: 1) iterate design when preliminary information is either ambiguous or precise, but unstable and 2) build buffers in the design definition to absorb foreseeable changes when the preliminary information lacks precision but is not ambiguous. Buffers can be designed out if downstream uncertainties resolve favorably before the buffers are physically executed.