Design coordination strategies in a 2D and BIM mixed-project environment: social dynamics and productivity

Despite the rapid spread of building information modelling (BIM), the majority of BIM projects are still conducted in a mixed-project environment: two-dimensional (2D) drawing and BIM. The design-coordination productivity and information-exchange patterns are analysed for a unique case where two towers, A and B, of a hospital project deployed two different design coordination strategies in a 2D and BIM mixed-construction environment. The tower A strategy coordinated designs using drawings as the main source of information and confirmed them using BIM (BIM-assisted coordination), whereas the tower B strategy coordinated designs using BIM and confirmed them using drawings (BIM-led coordination). The coordination productivity was 228% faster for tower B than for tower A. The frequency of design changes was much lower for tower B (0.42 times/drawing) than for tower A (2.13 times/drawing). As the result, the design coordination for tower A was delayed by 9.3 months, whereas tower B was completed rapidly and without any delay. A social network analysis revealed that the BIM-led coordination was supported by the relatively even distribution of information, the reduced control of an mechanical, electrical and plumbing (MEP) engineer over a project, and higher accessibility to the information for every project participant.