TY - CONF TI - An adaptive WIP controller framework for dynamic buffer management in modular construction C1 - Singapore, Singapore C3 - Proceedings of the 34th Annual Conference of the International Group for Lean Construction (IGLC 34) SP - 811 EP - 823 PY - 2026 DO - 10.24928/2026/0243 AU - Moghimi, Nima AU - Shamaee, Sahar H. AU - Yu, Haitao AU - Mei, Qipei AU - Gonzalez, Vicente A. AU - Hamzeh, Farook AD - Ph.D. Student, Department of Civil and Environmental Engineering, University of Alberta, Canada, nmoghimi@ualberta.ca, orcid.org/0009-0008-4733-1276 AD - Graduate Research Assistant, Department of Civil and Environmental Engineering, University of Alberta, Canada, hamedsha@ualberta.ca AD - R&D Lead, Landmark Homes, Edmonton, Canada, haitaoy@landmarkgroup.ca AD - Assistant Professor, Department of Civil and Environmental Engineering, University of Alberta, Canada, qipei@ualberta.ca AD - Hal Kvisle Professor and Tier 1 Canada Research Chair in Digital Lean Construction, Infrastructure Human Tech (IHT) Lab, Strategic Projects Insight Centre in Engineering (SPICE), Department of Civil and Environmental Engineering, Faculty of Engineering, University of Alberta, Canada, vagonzal@ualberta.ca, orcid.org/0000-0003-3408-3863 AD - Professor, Department of Civil and Environmental Engineering, University of Alberta, Canada, hamzeh@ualberta.ca, orcid.org/0000-0002-3986-9534 ED - Hamzeh, Farook ED - Poshdar, Mani ED - Garcia-Lopez,, Nelly P. AB - Lean construction principles emphasize maintaining production flow and managing variability to eliminate waste. However, in modular construction, high product mix and strict spatial constraints frequently disrupt this flow, rendering static buffering strategies ineffective. To address this challenge, this paper proposes an Adaptive WIP Control Framework structured in three integrated layers: a Digital Twin for stochastic simulation, an optimization layer for policy development, and a real-time execution layer. At the core of this framework is a novel hysteretic "Store-and-Release" control logic that dynamically regulates Work-in-Process (WIP) based on real-time buffer inventory, transforming the buffer from a passive queue into an active decoupling mechanism. The control logic was evaluated through a simulation-based case study of a prefabricated wall assembly line. Results demonstrate that the adaptive controller reduces downstream workload by 22% compared to unbuffered flow, effectively eliminating starvation waste. Unlike static time-buffers which sacrifice upstream speed for downstream stability, the adaptive approach optimizes total system performance without physical footprint expansion. This research contributes to Lean construction theory by establishing dynamic inventory control as a superior alternative to static scheduling for maintaining reliable flow in off-site construction. KW - Lean Construction KW - flow KW - work in progress/process (WIP) KW - buffer/buffer management KW - modular construction. PB - T2 - Proceedings of the 34th Annual Conference of the International Group for Lean Construction (IGLC 34) DA - 2026/06/22 CY - Singapore, Singapore L1 - http://iglc.net/Papers/Details/2538/pdf L2 - http://iglc.net/Papers/Details/2538 N1 - Export Date: 19 June 2026 DB - IGLC.net DP - IGLC LA - English ER -