Quantifying the Impact of Lean Construction Practices on Sustainability Performance in Chinese EPC Projects: A PLS-SEM Approach

Abstract

This study assesses the performance impact of lean construction practices in Engineering, Procurement, and Construction (EPC) projects in China. While lean methods have demonstrated substantial benefits in conventional construction, their implementation in the EPC context—characterized by higher complexity and integration—remains underexplored, particularly within the Chinese infrastructure sector. This research develops a structured framework that classifies lean practices into five functional categories: planning and scheduling (PS), process and workflow optimization (PWO), quality and safety enhancement (QSE), resource and maintenance (RM), and visualization and communication (VC). This study evaluates the influence of these practices on four key performance indicators: efficiency and resource management, quality and safety, stakeholder satisfaction, and organizational and market impact. Data were collected from 456 EPC stakeholders via a structured questionnaire and analyzed using Partial Least Squares Structural Equation Modeling (PLS-SEM). The findings reveal that PS, PWO, and QSE exert the strongest positive effects on performance, while RM and VC contribute in more context-specific ways. The results highlight the value of lean practices for improving operational performance, stakeholder engagement, and sustainability in complex project delivery systems and underscore the need for policy support and digital integration to enhance lean adoption in Chinese EPC sector.

1. Introduction

Improving project management efficiency, cost control, and sustainability has emerged as a core challenge in the global construction industry, particularly in Engineering, Procurement, and Construction (EPC) projects [1]. Traditional construction methods often fall short in meeting the increasing complexity of modern construction demands [2]. In response, lean construction, originating from innovative management practices in the manufacturing sector, aims to reduce waste, optimize construction processes, and enhance productivity while promoting efficient resource utilization and environmentally sustainable practices [3,4].

Numerous studies have shown that lean construction, through methods such as the final planning system (LPS) and just-in-time (JIT) delivery, significantly improves project delivery efficiency, reduces costs, improves quality, enhances stakeholder satisfaction, and supports environmental performance [5,6]. Furthermore, systematic reviews have confirmed that lean practices contribute to sustainable construction by promoting efficient resource utilization and minimizing environmental impacts [7]. These advantages have been widely recognized in different countries, highlighting the potential of lean construction in addressing key industry challenges [8,9,10]. However, despite its global success, the implementation of lean practices in certain contexts, such as China’s EPC sector, remains limited and faces unique challenges.

In China, lean construction is still in its early stages, with limited understanding and research mostly centered on public infrastructure, not EPC projects [11,12]. While some case studies have demonstrated potential benefits, such as improved efficiency and reduced emissions [13,14], most existing research focuses on public infrastructure, not the EPC delivery model. China’s construction sector, while vital to economic growth, contributes significantly to resource consumption and carbon emissions [15]. To this end, the government has introduced a number of policies since 2016 to vigorously promote EPC projects [16,17,18]. However, challenges such as cost overruns, schedule delays, and regulatory pressures persist [19], especially given the increasing technical and environmental complexity of EPC projects [20].

Compared with traditional delivery methods, EPC projects integrate design, procurement, and construction under a single contract, increasing management difficulty and process synchronization requirements [21,22]. Effective management of EPC projects requires advanced strategies and tools to ensure coordination across all phases and to reduce uncertainty [22], such as LPS for collaborative scheduling, JIT for process synchronization, and Total Quality Management (TQM) for continuous improvement [6]. However, most EPC projects continue to rely on target cost control and investment-focused strategies, with insufficient emphasis on value management and client-centered planning [23].

While a few studies have explored methods such as Building Information Modeling (BIM) and Target Value Design (TVD) in EPC contexts [23,24], the current literature lacks a comprehensive empirical analysis of how lean construction practices affect performance outcomes in Chinese EPC projects. This gap underlines the need for further investigation.

There is a clear need to investigate the applicability and benefits of lean practices in EPC projects within the Chinese context. This study seeks to address this gap by providing practical guidance for EPC project managers in China and laying the groundwork for further exploration of lean construction in complex engineering projects. The objectives of this research are as follows:

• To categorize lean construction practices in Chinese EPC projects into five groups and examine the extent to which they are adopted by project stakeholders.
• To evaluate the impact of different categories of lean practices on EPC project performance, considering four key performance indicators: efficiency and resource management, quality and safety, stakeholder satisfaction, and organizational and market influence.
• To apply Partial Least Squares Structural Equation Modeling (PLS-SEM) to test the relationship between lean construction practices and EPC project performance.

Using a structured approach, this study systematically examines the classification, adoption, and performance impact of lean construction practices in Chinese EPC projects. PLS-SEM analysis identifies critical relationships, offering insights for selecting effective lean strategies.

This paper is organized into five sections. Following the Introduction, Section 2 reviews the theoretical foundations of lean construction, its application in EPC projects, and the classification of lean practices, highlighting their potential contributions to project performance. Section 3 outlines the research methodology, including data collection, measurement design, and the use of PLS-SEM in the empirical analysis. Section 4 presents the research findings and discusses the impact of lean practices on key EPC project performance indicators. Section 5 concludes the study by summarizing the main insights, discussing both practical and theoretical implications, and suggesting directions for future research. This structured approach provides a systematic examination of lean construction in EPC projects and offers valuable guidance for both researchers and industry practitioners.

2. Literature Review

2.1. From Manufacturing to Construction: The Evolution of Lean

Lean construction originated from the Toyota Production System (TPS), which emphasizes maximizing value and minimizing waste through standardized processes and continuous improvement [25]. Koskela [26] was the first to formally introduce lean principles into the construction sector by developing the Transformation–Flow–Value (TFV) theory. This framework redefined construction production as a combination of input transformation, process flow, and customer value delivery.

The TFV model has since become a core theoretical foundation for applying lean principles in construction, aiming to improve value delivery, workflow coordination, and quality control [27]. Compared to traditional delivery models, EPC projects feature high levels of integration and concurrent execution across design, procurement, and construction phases. This creates a tightly coupled environment where disruptions in flow, delays in information exchange, or mismatched value expectations can rapidly cascade into broader inefficiencies [12]. Nonetheless, the practical implementation of lean in EPC settings remains limited, especially in China, due to factors such as insufficient policy support, rigid hierarchical organizational structures, low collaborative efficiency, and a lack of awareness regarding lean management benefits among stakeholders [23].

Furthermore, the unique structure of EPC projects, characterized by contractual integration, cross-disciplinary execution, and procurement-centered workflows, introduces challenges that may significantly influence the effectiveness and sequencing of lean practices [21,28]. There remains a notable lack of empirical research examining how these structural and organizational complexities influence the implementation and sequencing of lean practices in EPC contexts, especially within developing economies, where institutional and managerial environments differ markedly from those in mature markets.

2.2. Functional Classification and Research Gaps in Lean Construction for EPC Projects

Lean construction includes a wide range of tools, techniques and methods like LPS, JIT, Six Sigma, and TQM, which aim to reduce waste, enhance coordination, and improve workflow reliability and quality control in traditional construction settings [29,30,31]. These practices also promote continuous improvement and stakeholder integration, leading to more predictable schedules, better cost control, and enhanced value delivery [9].

Integrating lean practices with digital technologies such as Enterprise Resource Planning (ERP) systems enhances its impact by improving real-time data flow and interdisciplinary collaboration [32]. The combination of lean principles with prefabrication techniques has similarly shown benefits in improving efficiency, quality, and safety while reducing material waste and construction time [33].

To address the functional diversity of lean practices, researchers have proposed classification frameworks that group practices by their operational objectives. This is particularly important for EPC projects, where planning, procurement, and construction activities are integrated both contractually and temporally. In this context, coordination, resource flow, and regulatory compliance differ significantly from those in conventional project environments.

Table 1. Functional classification of lean construction practices for EPC projects.

Categories	Lean Practices
1. Planning and Scheduling (PS)	JIT and LPS [6]; TVD [23]; ERP [32];
	Concurrent Engineering [34].
2. Process and Workflow Optimization (PWO)	Continuous Improvement Programs [9];
	Kanban [35]; VSM [36];
	First Run Studies (Plan, Do, Check, Act—PDCA) [37].
3. Quality and Safety Enhancement (QSE)	Six Sigma [30]; TQM [31];
	Safety Improvement Program [38];
	Plan of Conditions and Work Environment in the Construction Industry (PCMAT) [39].
4. Resource and Maintenance (RM)	Use of Prefabricated Materials [33];
	Total Productive Maintenance (TPM) [40];
	5S Process [41].
5. Visualization and Communication (VC)	Increased Visualization [42];
	Information Management System (IMS) [43];
	Daily Huddle Meetings [44];
	Computer-Aided Design (CAD) [45].

presents a classification system tailored for EPC projects, dividing lean construction practices into five main categories: planning and scheduling, workflow optimization, quality and safety enhancement, resource maintenance, and communication and visualization.

This classification highlights the operational logic behind lean practices and serves as a structural foundation for this study’s empirical model. By grouping lean practices by function, the model aims to identify which types of practices most significantly affect EPC project performance. This is particularly relevant in EPC contexts, where procurement-driven decisions, compressed timelines, and fragmented coordination introduce implementation challenges [46].

Moreover, prior studies typically assess individual tools rather than evaluating how grouped functional categories influence performance across multiple dimensions, such as stakeholder satisfaction, resource efficiency, or market outcomes, highlighting a critical gap in lean construction research [47].

This study addresses this gap by adopting a functional classification tailored to EPC contexts and empirically investigating the relationships between grouped lean practices and four defined performance dimensions in Chinese EPC projects. The following section outlines the specific benefits reported in previous studies, forming the basis for this model development.

2.3. Performance Dimensions and the Benefits of Lean Practices in EPC Projects

Time and cost overruns remain persistent issues in construction, often causing delays, budget excesses, and low productivity [48]. Systemic problems such as weak quality control and inadequate safety management further elevate project risks [49]. Lean construction has emerged as a practical solution to these issues by reducing waste, streamlining workflows, and improving overall value delivery. Studies have reported measurable benefits, including shortened project duration, cost savings, and enhanced productivity [50,51].

In addition to internal process improvements, lean construction has been linked to broader project outcomes such as stakeholder alignment and enhanced market competitiveness, particularly through improved client satisfaction and supplier collaboration [4].

Table 2. Reported benefits of lean construction implementation from previous studies.

Author	Reduced Construction Time	Better Inventory Control	Quality Improvement	Customer Satisfaction	Process Improvement	Employee Satisfaction	Increased Market Share	Increased Productivity	Improved Supplier Relationship	Better Health and Safety Record
[1]	*	*			*
[8]			*
[9]		*				*
[38]										*
[50]	*
[51]					*
[52]	*				*
[53]			*
[54]				*
[55]						*
[56]	*		*				*	*
[57]								*
[58]								*
[59]									*
[60]									*
[61]										*

“*” indicates the benefit mentioned or emphasized in the referenced study.

presents a synthesis of these benefits as reported in the conventional construction literature.

However, few studies have empirically examined how functionally grouped lean practices perform in construction projects, as existing research often focuses on isolated tools or individual outcomes [47]. Within the context of EPC projects, recent studies highlight the limited integration of lean methods in practice and the challenges of achieving systematic implementation [28].

To address this gap, the present study adopts a functional classification approach and develops a structured framework that links grouped lean practices to project outcomes across four key performance dimensions relevant to EPC contexts, as outlined in

Table 3. Performance dimensions and corresponding benefits of lean construction in EPC projects.

Categories	Benefits
1. Efficiency and Resource Management (ERM)	Reduced construction time
	Better inventory control
	Increased productivity
2. Quality and Safety (QS)	Quality improvement
	Better health and safety records
3. Organization and Market Impact (OMI)	Process improvement (internal improvements)
	Increased market share (external market impact)
4. Stakeholder Satisfaction (SS)	Customer satisfaction
	Improved supplier relationship
	Employee satisfaction

.

• Efficiency and Resource Management (ERM) refers to improvements in time, cost, and material usage. Indicators include reduced schedule delays, lower waste rates, and optimized resource allocation [1].
• Quality and Safety (QS) captures outcomes related to product quality and worksite safety. This includes defect reduction, rework minimization, and incident rate improvement [38].
• Organizational and Market Impact (OMI) covers internal outcomes (e.g., process improvement, cross-functional learning, process maturity) and external outcomes (e.g., increased market share, increased project acquisition, enhanced reputation) [56].
• Stakeholder Satisfaction (SS) reflects the perceptions of clients, suppliers, and employees regarding project communication, responsiveness, and collaboration effectiveness [62].

It is worth noting that this dual structure within OMI reflects the strategic expectations for EPC firms to demonstrate both operational maturity and market competitiveness [20,56], aligning with the multi-stakeholder nature of EPC projects. This construct is measured through items that capture these two aspects, ensuring alignment between theoretical framing and empirical indicators based on established research on lean implementation outcomes.

At the same time, it is important to clarify that RM focuses on optimizing tangible project-level inputs, such as labor, materials, and time, whereas process improvement, as part of OMI, emphasizes systemic organizational changes. These include improvements in coordination mechanisms, procedural maturity, and long-term learning capacity, which are conceptually and empirically distinct from RM.

This classification offers a structured lens for analyzing lean implementation in complex EPC environments. It facilitates a clearer understanding of how functionally grouped lean practices impact project performance beyond conventional evaluation metrics. These four dimensions also serve as the dependent constructs in the empirical model, bridging theoretical categorization with performance measurement.

2.4. Research Gap and Study Motivation

While lean construction practices have been widely studied in conventional building projects, their application in EPC environments—particularly in China—remains limited, fragmented, and largely descriptive. Most existing studies adopt tool-level or case-based approaches within traditional delivery models, often overlooking the complex, overlapping, and procurement-driven nature of EPC workflows that require continuous coordination across project phases [12]. As a result, the current literature lacks a structured, theory-driven framework for evaluating how functionally grouped lean practices influence multiple dimensions of performance under EPC-specific contractual and organizational conditions.

To address this gap, this study develops and empirically tests a functional classification of lean construction practices tailored to EPC project environments. Specifically, it examines how these categorized practices influence four critical dimensions of project performance: efficiency and resource management, quality and safety, stakeholder satisfaction, and organizational and market impact.

By offering a rigorous, empirically validated performance evaluation model, this study contributes to bridging the methodological and contextual gaps in the current lean construction literature, especially in the under-researched field of Chinese EPC projects.

The following section outlines the research methodology, including data collection, measurement model design, and structural model evaluation, to ensure a rigorous empirical assessment of lean construction effectiveness.

3. Materials and Methods

This study adopts a quantitative approach to examine how lean construction practices affect EPC project performance in China. The PLS-SEM technique is employed to assess the relationships between five categories of lean practices—PS, PWO, QSE, RM, and VC—and four key performance indicators: ERM, QS, SS, and OMI.

The methodology involves survey design, data collection, hypothesis development, and statistical analysis to ensure a rigorous empirical examination of the effectiveness of lean construction in EPC project settings.

3.1. Research Hypotheses

Based on the structured classification of lean practices and the identification of key performance indicators, the following hypotheses are proposed to empirically examine their interrelationships:

• H1: Different categories of lean construction practices have a significant impact on the overall performance of EPC projects.
• H2: The influence of lean construction practices varies across different performance indicators in EPC projects.

3.2. Survey Design

Based on the hypotheses outlined above, a structured survey was developed to capture the relevant empirical data. To conduct this study, an extensive literature review was first carried out to establish the theoretical foundation and refine the research framework. The survey was designed using validated constructs from prior studies on lean construction and EPC project performance. A questionnaire survey was then designed and distributed to relevant stakeholders involved in EPC projects across China. The survey focused on the extent of lean construction practice adoption and stakeholders’ perceptions of its impact on project performance. A questionnaire approach was chosen to capture diverse perspectives and enhance generalizability through large-sample coverage.

Based on a comprehensive literature review, a structured questionnaire was developed using a five-point Likert scale (1 = strongly disagree, 5 = strongly agree). The five-point Likert scale is widely used in similar research settings due to its practicality and reliability [63]. The instrument comprised two parts: respondent demographics and 30 measurement items, which were as follows:

• Respondent demographics, including organization type, educational background, work experience.
• The extent of lean construction practice adoption in Chinese EPC projects (20 items).
• Perceived benefits of lean construction, assessing stakeholder views on its impact on project performance (10 items).

Prior to full distribution, the questionnaire was internally reviewed and pre-tested with a small group of EPC stakeholders to ensure item clarity and contextual relevance. Several procedural remedies were also implemented to reduce the risk of common method bias. These included ensuring respondent anonymity, grouping constructs into separate sections of the questionnaire, and using neutral, non-leading language throughout the instrument.

3.3. Data Collection and Sampling

This study employed random sampling to target key EPC stakeholders, including general contractors, subcontractors, architects, project managers, clients, suppliers, academics, and government officials. A total of 458 questionnaires were collected, of which 2 were excluded due to invalid responses. Ultimately, 456 valid responses were retained for analysis. Data were collected through both online and offline channels to maximize the response rate and ensure sample diversity. The diverse industry backgrounds of respondents further enhanced the generalizability of the findings. Descriptive statistics summarizing respondent profiles are presented in the Results section to provide context for the analysis.

3.4. Data Analysis

This study employed SmartPLS to conduct PLS-SEM in order to evaluate the impact of different categories of lean practices on EPC project performance. The analysis included the structural model and reliability testing. Path coefficients, coefficients of determination (R²), and significance levels (p-values) were used to assess the relationships between lean practices and performance indicators. Cronbach’s Alpha (α = 0.961) confirmed high internal consistency of the measurement scale, ensuring its reliability. Descriptive statistics and data validation were performed using SPSS Version 29 to ensure data accuracy and provide a solid foundation for the PLS-SEM analysis. As the measurement model is formative with single-item constructs, conventional metrics such as Composite Reliability and AVE were not applicable. Instead, collinearity diagnostics were performed, and all Variance Inflation Factor (VIF) values were found to be 1.000 (VIF < 3.3), indicating no multicollinearity issues among the formative indicators.

3.5. Justification for Using PLS-SEM

Given the model’s structure and the nature of the indicators, PLS-SEM was selected for its strengths in predictive research and its suitability for handling complex models with formative constructs [64]. Unlike Covariance-Based SEM (CB-SEM), it handles small samples, complex models, and non-normal data more effectively. It also offers superior capabilities in handling formative measurement models [65]. In addition, it is more robust to missing data, making it well-suited for real-world survey research and effective in identifying key influencing factors [66]. PLS-SEM is widely used in exploratory studies and is effective in evaluating the multidimensional impacts of lean construction [67]. Given its flexibility in modeling the complexities of lean construction, it is considered the most appropriate analytical method for this study [64].

The results are illustrated using tables and structural model diagrams to facilitate understanding. These visualizations highlight the effects of different lean practices on EPC project performance and support clearer interpretation.

4. Result and Discussion

4.1. Respondent Profile

Table 4. Demographic characteristics of respondents.

Profile	Classification	Frequency	Percentage (%)
Education level	PhD	35	7.68
	Master’s	75	16.45
	Bachelor’s	218	47.81
	Diploma and below	128	28.07
Work experience (Years)	0–5	137	30.04
	6–10	252	55.26
	11 and above	67	14.69
Organization Type	Architect	18	3.95
	Client	92	20.18
	General contractor	34	7.46
	Subcontractor	69	15.13
	Specialty contractor	91	19.96
	Supplier	96	21.05
	Project management	12	2.63
	Academia	32	7.02
	Government	12	2.63

summarizes the demographic characteristics of the respondents. Most participants held a bachelor’s degree (47.81%), and over half had 6–10 years of work experience. The sample covered a broad range of EPC stakeholders, including clients, contractors, suppliers, and government representatives, to ensure both the representativeness and the contextual relevance of the data.

4.2. The Impact of Different Categories of Lean Construction Practices on Overall Performance

The PLS-SEM analysis confirmed a strong explanatory power (R² = 0.932), showing that the five lean practice categories—PS, PWO, QSE, RM, and VC—together explain 93.2% of the variance in EPC project performance. The remaining 6.8% of the variance may result from external factors beyond the study scope—such as organizational culture, regulations, market conditions, or other project-specific variables. Given that an R² value above 0.75 indicates strong explanatory power [68], this result validates the robustness of the model and the relevance of the selected predictors. Path coefficient analysis (Figure 1.) further confirmed that all categories of lean practices had statistically significant effects on performance (p < 0.001), with varying degrees of influence, highlighting their distinct contributions to overall project outcomes.

Among the five lean construction categories, notable differences were observed, PS had the greatest impact on performance (β = 0.308, p < 0.001), underscoring its critical role in workflow optimization, delay reduction, and project coordination. Practices such as JIT, ERP, the LPS, and TVD have made significant contributions to these improvements in efficiency [69].

PWO (β = 0.234, p = 0.000) and QSE (β = 0.221, p = 0.000) also demonstrated significant, though slightly lower, impacts. PWO relies on system-based lean practices such as Kanban, Value Stream Mapping (VSM), continuous improvement programs, and the PDCA cycle to streamline workflows and minimize waste. However, challenges in coordination within centralized decision-making structures and limited progress in digital transformation may hinder effective implementation [70].

QSE contributes to high standards of project execution through safety planning, TQM, Six Sigma, and PCMAT, reducing defects and improving the work environment. However, its slightly lower impact compared to PS and PWO suggests that the digital integration of quality and safety practices may lag behind productivity-driven improvements, which could limit their effectiveness in lean adoption [70].

RM (β = 0.119, p = 0.000) and VC (β = 0.129, p = 0.000) showed relatively weaker impacts. Although RM enhances operational stability through practices such as TPM, prefabricated materials, and 5S processes, its direct influence on performance remains limited. Similarly, VC supports communication and decision-making through visualization tools, IMS, daily meetings, and CAD, contributing to coordination efforts, but its direct contribution to performance outcomes is comparatively modest.

The results suggest that EPC organizations should focus primarily on PS, PWO, and QSE to enhance overall project performance. Although RM and VC showed weaker impacts, they remain useful in specific situations. Strengthening equipment maintenance and team communication can support projects operating under resource constraints or tight schedules [71]. These findings emphasize the importance of strategic planning and continuous process optimization. They also highlight the need to integrate quality, resource, and communication strategies to fully realize the benefits of lean construction.

4.3. The Impact of Different Categories of Lean Construction Practices on Various Performance Indicators

The SmartPLS analysis indicated that all performance indicators—ERM, OMI, QS, and SS—had R² values exceeding 0.750, demonstrating strong explanatory power (

Table 5. R² Values of performance indicators.

Performance Indicator	R² Value
ERM	0.847
OMI	0.786
QS	0.778
SS	0.827

). This confirms the robustness of the proposed framework and its ability to capture key relationships within the dataset. The results validate the model’s goodness-of-fit and provide empirical support for its predictive capability and theoretical foundation.

Table 6. The impact of different types of lean practices on different types of project performance indicators.

	Path Coefficient	Sample Mean (M)	Standard Deviation (STDEV)	T Statistics (|O/STDEV|)	p Values
PS -> ERM	0.255	0.255	0.060	4.271	0.000
PS -> OMI	0.276	0.278	0.068	4.065	0.000
PS -> QS	0.184	0.184	0.063	2.904	0.004
PS -> SS	0.400	0.401	0.064	6.270	0.000
PWO -> ERM	0.258	0.259	0.054	4.746	0.000
PWO -> OMI	0.150	0.150	0.065	2.300	0.021
PWO -> QS	0.305	0.305	0.067	4.572	0.000
PWO -> SS	0.167	0.166	0.061	2.727	0.006
QSE -> ERM	0.178	0.178	0.048	3.740	0.000
QSE -> OMI	0.296	0.295	0.061	4.842	0.000
QSE -> QS	0.180	0.180	0.059	3.032	0.002
QSE -> SS	0.191	0.191	0.058	3.295	0.001
RM -> ERM	0.133	0.132	0.043	3.110	0.002
RM -> OMI	0.164	0.162	0.055	2.967	0.003
RM -> QS	0.149	0.148	0.055	2.713	0.007
RM -> SS	0.026	0.026	0.050	0.522	(0.602)
VC -> ERM	0.141	0.141	0.057	2.480	0.013
VC -> OMI	0.044	0.045	0.060	0.746	(0.456)
VC -> QS	0.107	0.108	0.069	1.554	(0.120)
VC -> SS	0.163	0.164	0.058	2.796	0.005

presents the path coefficient analysis, revealing the relative impact of different lean construction practices on performance indicators. Most hypothesized relationships were statistically significant (p < 0.05), further confirming the critical role of lean approaches in enhancing project performance.

Among the significant relationships, PS had the strongest impact on SS (β = 0.400, p = 0.000), indicating that structured planning mechanisms can enhance client satisfaction, supplier collaboration, and employee confidence. Methods such as JIT and the LPS help optimize scheduling, improve project transparency, and strengthen resource coordination, thereby fostering stakeholder trust. Shehab et al. [72] demonstrated that LPS enhances planning reliability by minimizing variability in construction workflows, contributing to more predictable project outcomes.

The decision-making behaviors of stakeholders critically influence the stability and widespread adoption of EPC delivery models. Wang and Liu [73] developed a tripartite evolutionary game model involving government agencies, project owners, and construction enterprises to systematically analyze how governmental incentives, owner selection criteria, and contractor capacity enhancement collectively drive EPC development.

Their findings reveal that well-designed governmental incentive policies not only strengthen the implementation motivation of contractors and owners but also mitigate project coordination challenges arising from ambiguous contractual constraints and responsibility allocation. Consequently, lean planning and scheduling tools in construction management not only optimize operational efficiency but also foster effective multi-stakeholder collaboration in EPC projects. While the model treats PS as a driver of performance, it is also plausible that more mature or better-performing EPC projects are more likely to adopt structured planning and scheduling systems. This potential reverse causality should be considered when interpreting the results. Furthermore, Adhi and Muslim [62] emphasize that proactive stakeholder engagement constitutes a critical success factor for lean methodology implementation, particularly in sustainable construction practices.

PWO had a significant impact on QS (β = 0.305, p = 0.000), highlighting the role of lean tools and methods such as continuous improvement programs and Value Stream Mapping (VSM) in ensuring high-quality project outcomes. These practices enhance quality control and safety by minimizing waste, optimizing workflows, and improving production efficiency.

Under the EPC model, construction firms must integrate design, procurement, and construction phases. Lean tools such as VSM and continuous improvement programs play a critical role in shortening project durations, improving quality, and controlling costs [12]. Previous studies have confirmed that through design optimization, improved construction organization, and early procurement planning, EPC projects can increase construction efficiency and reduce non-value-adding activities [28].

QSE played a critical role in influencing OMI (β = 0.296, p = 0.000), underscoring the effectiveness of TQM and Six Sigma in enhancing corporate reputation, market competitiveness, and process standardization. Beyond improving project quality, these integrated lean quality management methods also support the long-term sustainability of construction firms. Al Hosani [12] found that the application of Six Sigma and TQM in EPC improves construction quality, reduces rework, and strengthens market competitiveness. Furthermore, as EPC projects often operate under fixed-price contracts, construction firms bear greater responsibility for quality management. The implementation of TPM and 5S site management is therefore essential for reducing uncertainty in construction performance.

The weak association between RM and SS (β = 0.026, p = 0.602) may indicate that maintenance-oriented practices such as TPM and 5S primarily enhance internal operational efficiency but have limited visibility or impact on external stakeholders—particularly in the absence of a supportive organizational culture [74]. In EPC environments, the effectiveness of RM practices may be further constrained by fragmented contract structures, complex supply chain dynamics, and limited cross-phase coordination. Since these practices are typically contractor-led, their influence on client satisfaction may be less pronounced compared to interventions during the design and procurement phases [12,73].

VC practices showed limited effects on OMI (β = 0.044, p = 0.456) and QS (β = 0.107, p = 0.120), which may reflect their indirect role in project performance. Tools such as IMS and CAD primarily facilitate information exchange and visualization, but their effectiveness is contingent upon integration with quality assurance mechanisms and workflow execution. Achieving this integration can be particularly difficult in EPC contexts, where multiple stakeholders, siloed responsibilities, and inconsistent digital maturity often hinder seamless implementation [46].

Taken together, the differentiated effects across lean categories suggest a need for tailored implementation strategies. In summary, the findings underscore the importance of a balanced lean implementation strategy. EPC firms should emphasize planning, process optimization, and quality control while addressing integration challenges in resource and communication management to maximize performance benefits.

5. Conclusions

5.1. Key Findings

This study employed PLS-SEM to empirically assess the impact of five functionally grouped lean construction practices (PS, PWO, QSE, RM, VC) on four key performance dimensions (ERM, QS, OMI, SS) in EPC projects in China. The findings confirm the effectiveness of these lean practices in improving efficiency, enhancing quality, controlling costs, and increasing stakeholder satisfaction.

The detailed analysis revealed that PS practices exerted the strongest and most consistent positive effects across all performance dimensions, particularly on SS (β = 0.400, p < 0.001). PWO also had a significant impact, especially on QS (β = 0.305, p < 0.001). QSE played a key role in influencing OMI (β = 0.296, p < 0.001).

In contrast, the overall effect of RM was relatively weak, with no significant impact observed on SS (β = 0.026, p = 0.602). While VC practices influenced ERM and SS to some extent, they showed no significant effects on OMI (β = 0.044, p = 0.456) or QS (β = 0.107, p = 0.120).

These differentiated results suggest that coordination- and quality-oriented lean practices (PS, PWO, QSE) play a central role in enhancing EPC project performance. In contrast, RM and VC may support internal process efficiency but have limited influence on broader organizational or stakeholder outcomes. Therefore, practitioners are encouraged to prioritize investment in high-impact areas such as planning, workflow design, and safety systems while also strengthening the institutional support necessary to unlock the full value of resource management and visualization initiatives.

This study contributes to the existing literature by quantitatively assessing the effectiveness of lean construction practices within EPC project environments, addressing the gap in prior empirical research. The findings highlight the importance of structured planning, continuous process optimization, and digital integration. Beyond operational improvements, lean practices also help reduce rework, shorten construction duration, and enhance material efficiency, thereby supporting environmental sustainability goals.

5.2. Practical Implications

The findings of this study offer concrete guidance for EPC project stakeholders aiming to enhance project performance through lean construction practices. Project managers should prioritize the adoption of structured planning and scheduling practices, such as the LPS, given their demonstrated strong influence on efficiency, resource management, and stakeholder satisfaction.

PWO practices should also be systematically implemented to improve synchronization and reduce operational waste, particularly during the transition phases between design, procurement, and construction. QSE initiatives, including TQM programs, are crucial for ensuring compliance with increasingly stringent regulatory standards.

Furthermore, the integration of digital technologies can facilitate real-time monitoring, enhance interdisciplinary coordination, and support lean workflow optimization. Organizations should also invest in change management and lean awareness training to overcome resistance to new practices. Policymakers are encouraged to develop EPC specific lean adoption guidelines, offering incentives for projects that achieve measurable improvements in efficiency, quality, and sustainability.

5.3. Limitations and Future Research

This study has several limitations that warrant attention. First, the sample was drawn from EPC projects within a single regional context in China, which may affect the generalizability of the findings. Future studies should extend the geographic scope and examine regional or sectoral differences in lean adoption.

Second, while key lean practices were measured, contextual variables such as organizational culture, implementation maturity, and stakeholder collaboration were not included. Incorporating these moderators in future models could enhance explanatory depth.

Third, the use of non-stratified, self-reported data may limit the detection of contextual patterns (e.g., project type, region, industry sector) and introduce bias. Future research should adopt stratified sampling and triangulate findings with objective or multi-source data to enhance robustness.

Finally, while this study primarily focused on traditional lean practices, emerging technologies such as Digital Twins, Artificial Intelligence (AI)-based project management, and Internet of Things (IoT) integration were not explored in depth. Future research should explore how such tools can complement lean construction in complex EPC environments.