A solution to just-in-time delivery for off-site construction: A conceptual model

Off-site construction is receiving increasing attention as this construction method offers such benefits as improved productivity, shortened duration, greater quality, less whole-life cost, and less environmental impact. The concept of just-in-time has been applied in the manufacturing industry, improving performance and reducing waste; however, it has not been commonly used in the construction industry. When optimal delivery dates of components deviate from the schedule due to unexpected events, contractors and manufacturers tend to comply with contracts instead of seeking coordination to achieve just-in-time, which results in non-optimal solutions. In addressing this issue, the proposed conceptual model incorporates a dynamic and distributed solution: (1) manufacturers provide the surcharges or incentives of potential delivery changes via an information-sharing platform; (2) based on data from manufacturers and on-site resources, contractors carry out automated changes of the delivery plans when their progress deviates from the assembly schedule; (3) contractors make possible automated changes to the assembly schedule when manufacturers offer incentives for delivery delay. This paper investigates the development of just-in-time application in prefabricated building and proposes a solution to reduce the time and storage waste resulted from underutilised resources in component delivery. The proposed model incorporates a data-sharing platform, dynamic resource management system of manufacturers and optimisation system of contractors, which encourages stakeholders to coordinate to reach optimal. The model is expected to contribute to just-in-time delivery with dynamic compensation and offer a solution to balance the benefits of stakeholders.