Mechanical, Electrical, and Plumbing (MEP) systems construction is one of the most resource-intensive and coordination-critical components of building projects. However, many digital transformation efforts in construction remain fragmented, technology-driven, and weakly connected to process improvement and sustainability outcomes. This study addresses this gap by developing an Industry 4.0–enabled Lean–Green framework that explicitly links digital technologies to MEP process optimisation and environmental performance. Rather than viewing Industry 4.0 tools as isolated solutions, the research examines how key digital technologies—Building Information Modelling (BIM), Industrial Internet of Things (IIoT), Digital Twins, and Artificial Intelligence (AI)—interact with Lean principles such as flow stabilisation, waste elimination, and right-first-time execution, and how they relate to Green construction objectives including energy efficiency, material optimisation, and carbon reduction. The study adopts a structured methodology combining systematic literature synthesis, technology–process mapping, industrial benchmarking, pilot case study integration, and design science–based framework development to identify where digital technologies create measurable Lean–Green synergies across MEP workflows. The primary contribution is a tri-layer Industry 4.0–enabled Lean–Green framework (I4LGF–MEP) consisting of: (1) a Lean process optimisation layer, (2) a Green sustainability performance layer reflecting environmental impacts, and (3) a digital intelligence layer supported by cyber-physical feedback loops. At the centre of the framework is a Cyber-Physical Lean–Green Loop (CPLGL), where real-time data from MEP activities is used to continuously evaluate and improve both process efficiency and environmental performance. The findings indicate that digitalisation delivers value only when technologies are clearly aligned with Lean mechanisms and sustainability metrics, providing a structured foundation for advancing Lean and sustainable MEP construction.

Keywords

Industry 4.0, Lean Construction, Green Construction, MEP Systems, Cyber-Physical Systems, Digital Twins