Stage-Conditioned Organization–Data Connections in Collaborative Decision Events: Evidence from a Supertall Building Project

Process-oriented BIM research has documented coordination workflows and design decisions, but project records rarely show how technical evidence becomes a basis for joint judgment and how confirmed outcomes become controlled project information for subsequent tasks. This study develops an auditable event-level framework and applies a retrospective explanatory embedded single-case design to a 266 m mixed-use supertall building. It reconstructs 31 collaborative decision events from 266 evidence fragments across 41 archival records. Within the case, scheme decision-making and specialist design centered on establishing a defensible design basis; design development linked joint review, responsibility assignment, and controlled updates of models, drawings, and issue records to establish a shared cross-disciplinary baseline; and construction detailing and implementation emphasized translating site and procurement changes into the current executable project state. Changed conditions could reopen joint judgment before controlled project information was updated. Comparable events revealed distinct evidentiary discontinuities: analytical outputs were sometimes retained without traceable use in joint judgment, decisions without traceable controlled write-back, and updated records without documentation of the preceding judgment process. Separating these transitions clarifies why similar digital tools and organizational arrangements produce different information outcomes and provides a traceable, stage-conditioned basis for design justification, baseline formation, implementation control, and cross-stage continuity.