Purpose - The purpose of this paper is to clarify the CSCW in collaborative 4D modelling and its user interface (UI)/interaction designs for prototyping. Four-dimensional (4D) modelling technology has potentials to integrate geographically dispersed planners to achieve collaborative construction planning. However, applying this technology in teamwork remains a challenge in computer-supported collaborative work (CSCW).Design/methodology/approach - The research adopted user-centred design (UCD) methodology to investigate a usable 4D collaboration prototype through analysis, design and usability testing. By applying CSCW theories, it first clarified the meaning of 4D CSCW to formulate design propositions as design target. By leveraging UCD theories, subsequently, the first-stage research sought an optimal standalone 4D modelling prototype following a parallel design approach. At the second stage, it further investigated into a collaborative 4D modelling prototype using an iterative design. It adopted collaborative task analysis into the UI/interaction design extension for a collaborative prototype based on results obtained from the first stage. The final usability testing was performed on the collaborative prototype to evaluate the designed CSCW and UI in a controlled geographically dispersed teamwork situation.Findings - The test results and user feedback verified their usability. It also disclosed design weaknesses in collaborators' awareness and smooth tasks' transitions for further enhancement.Originality/value - The combination of CSCW and UCD theories is practical for designing collaborative 4D modelling. It can also benefit designs for collaborative modelling in other dimensions like cost analysis, sustainable design, facility management, etc. in building information modelling.Published versio
