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A Review of the Current State of Lean Construction in Nairobi City

County

Joyreen Mwende Ngei

, Sylvester Munguti Masu

, Lucy M. Nyabwengi

The Technical University of Kenya, Nairobi, Kenya

DOI: https://doi.org/10.51244/IJRSI.2025.120800307

Received: 02 Sep 2025; Accepted: 08 Sep 2025; Published: 08 October 2025

ABSTRACT

The construction industry in Nairobi City County, Kenya, plays a critical role in urban development but

continues to face challenges related to inefficiencies, cost overruns, and waste generation. Lean Construction

(LC), a philosophy derived from the Toyota Production System, offers a framework for enhancing productivity

through waste minimization and value creation. This article reviews the current state of LC implementation in

Nairobi City County by drawing on both global literature and empirical findings from recent field research.

The study reveals that while awareness of LC is relatively high (70%), actual implementation remains low

(36%), with tools such as 5S, Just-in-Time (JIT), and the Last Planner System (LPS) being partially applied.

The most significant waste sources identified were inventory waste (58%), labour inefficiency (53%), and

waiting time (41%). Barriers to implementation include lack of awareness, resistance to change, fragmented

supply chains, and inadequate training. The findings highlight the potential of LC in addressing inefficiencies,

but greater institutional support, capacity building, and policy integration are necessary to realize its full

benefits in Nairobi’s construction sector.

Keywords: Lean Construction, Waste Management, Nairobi City County, 5S, Just-in-Time, Last Planner

System

INTRODUCTION

The construction industry contributes significantly to Kenya’s economic growth, accounting for approximately

7% of the national GDP. However, the sector is characterized by inefficiencies manifested in project delays,

cost overruns, and high levels of material waste. This study focuses on Nairobi City County, as Kenya's capital

and largest urban area; it is at the forefront of the country's construction activities as evidenced by NCA that it

records the highest number of building permits (NCA, n. d). The county's construction projects are often large-

scale and complex, making them prime candidates for lean construction techniques. The county experiences

rapid urbanization and infrastructural development, resulting in a high volume of construction projects.

However, like the rest of the country, Nairobi's construction sector is plagued by inefficiencies and waste levels

are particularly high, undermining both profitability and sustainability. The implementation of lean

construction techniques in Nairobi could provide a model for the rest of the country. According to Wachira

(2020), a case study done of Nairobi City County's construction projects reveals that adopting lean construction

can lead to significant waste reduction and enhanced efficiency. Studies show that projects, which have

implemented lean methodologies, such as pull planning and value stream mapping, have reported a 30%

reduction in waste and a 20% decrease in project delays. These results underscore the potential of lean

construction to transform the construction landscape in Nairobi and beyond (Nganga, 2020).

Lean Construction (LC) has emerged as an alternative project management philosophy aimed at reducing

waste and enhancing efficiency. Originating from the Toyota Production System, LC emphasizes value

INTERNATIONAL JOURNAL OF RESEARCH AND SCIENTIFIC INNOVATION (IJRSI)

ISSN No. 2321-2705 | DOI: 10.51244/IJRSI |Volume XII Issue IX September 2025

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generation for the client while systematically eliminating non-value-adding activities (Koskela, 1992). Lean

construction aims to improve efficiency, reduce waste, and enhance quality and safety on construction sites.

Internationally, the adoption of lean construction has demonstrated significant improvements in project

delivery and waste management. For instance, a study by Azhar et al. (2013) highlighted that lean construction

techniques reduced construction waste by up to 60% and improved project completion times by 30% in several

case studies across the United States and Europe. Globally, lean tools such as 5S, Just-in-Time (JIT),

Kaizen,and the Last Planner System (LPS) have demonstrated effectiveness in improving project delivery.

However, the uptake of these tools in Africa, and specifically Nairobi, remains relatively low. This review

explores the current state of LC adoption in Nairobi, drawing on both empirical findings and literature.

LITERATURE REVIEW

Lean Construction was derived from Lean Production whose foundation commenced with the introduction of

Toyota Production System (TPS) spearheaded by Taiichi Ohno of Toyota Motor Company (Ohno, 1988). TPS

aimed at removing any kind of waste and inconsistency in the production system. TPS consists of two pillars

that are Just-in-Time (JIT) and Jidoka (Ohno, 1988; Liker, 2004; [Jasti et al., 2014]). According to Sacks et al.

(2020), the foundation of lean construction was formed through the proposition of the transformation–flow–

value (TFV) theory by Koskela (1992) and the development of the lean project delivery system by Ballard

(2003). TFV refers to the conceptualization of the production process through three key elements, which are

transformation that is, production of inputs into outputs; flow which is movement that is reliable and

continuous; and value, that is, what the customer needs and pays for it ([Ajayi et al., 2019]; Nguyen &

Arkhavian, 2019;). Lean project delivery system, according to Ballard and Howell (2023), links five phases of

the lifecycle, which are project definition, lean design, lean supply, lean assembly, and use. The lean project

delivery system addresses construction as production, and reliable production management is of prime

importance in lean project delivery systems, which is realized by utilizing the last planner system. Globally, the

implementation of lean construction varies significantly across regions. In developed economies, lean practices

are often integrated with digital technologies such as Building Information Modelling (BIM) ([Sacks et al.,

2020]). In contrast, African contexts face structural and institutional barriers, including inadequate training and

fragmented project delivery systems (Aigbavboa & Thwala, 2019).

Studies in Uganda and Nigeria have reported similar challenges, where lean awareness is moderate but

adoption is weak due to cultural resistance and resource limitations ([Alinaitwe et al., 2019]). In Kenya, while

lean principles have been acknowledged in academic discourse, empirical evidence of widespread application

remains limited.

RESEARCH METHODOLOGY

This review draws on both secondary literature and primary research conducted in Nairobi City County. A

mixed-methods design was adopted to provide a comprehensive perspective. Survey research through

Structured questionnaires were administered to 132 construction professionals, including contractors, project

managers, site supervisors, engineers, Architects and quantity surveyors. A five-point Likert scale was used to

assess awareness, familiarity and implementation, of lean practices. 10 semi-structured interviews were

conducted with senior engineers, Contractors and project managers to capture deeper insights into challenges

and opportunities of lean adoption. Additionally, Direct observations were carried out across eight active

building construction sites to verify the extent of lean application in practice and to identify visible sources of

waste. Quantitative data were analyzed using descriptive statistics (SPSS) and Chi-square tests to examine

relationships between lean practices and waste reduction. Qualitative data from interviews and observations

were coded thematically to capture emerging patterns. This methodology ensured triangulation of findings,

enhancing both reliability and validity.

INTERNATIONAL JOURNAL OF RESEARCH AND SCIENTIFIC INNOVATION (IJRSI)

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RESULTS AND DISCUSSION

Awareness Levels

Survey data showed that 70% of construction professionals in Nairobi are aware of LC principles. This

demonstrates growing recognition of LC as a viable approach to project management. However, awareness is

often theoretical rather than practical, with limited exposure to structured lean training programs.

Table 4.1: Awareness of Lean

No. of Respondents

Frequency

Aware

69.69

Unaware

30.30

Source: Study survey, 2025

Ayarkwa et al. (2021) argue that awareness is critical for effective uptake of lean construction practices in

emerging markets. This shows that most of the respondents (70%) were aware of lean construction in the

industry

Implementation of Lean Tools

Table 4.2 shows the level of implementation of lean construction within building sites as reported by the

respondent’s. The data showed that 38% of the respondents implemented lean construction moderately within

their construction sites. Whereas 25% of the respondents indicated that they rarely implemented lean

construction practices.

Table 4.2: Level of Lean Implementation

No. of Respondents

Percentage

Yes, extensively

12.12%

Yes, Moderately

37.88%

Rarely

25%

Not at all

15.15%

Not sure

9.84%

Source: Study survey, 2025

A study done by Ahmed et. al. (2020), showed that the level of lean construction implementation in Sri Lanka

was not rigid and the awareness minimal, whereas a comparison with the United Kingdom Construction

Industry showed that awareness was increased and implementation of lean construction practices were also

more evident. Additionally, a study done by Marhani et. Al. (2019) showed that with increased awareness of

lean construction practices, there was an increased implementation of lean practices within construction sites.

INTERNATIONAL JOURNAL OF RESEARCH AND SCIENTIFIC INNOVATION (IJRSI)

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A review of the familiarity and extent of implementation of Lean construction practices within the construction

sites showed that that JIT Material delivery, Value engineering, 5S site organization for improving site

organization, Modular construction, and visual management and are the most familiar lean construction

practices. Additionally, Value engineering, 5S site organization, JIT Material Delivery for minimizing excess

inventory and storage costs, and The Last Planner system for enhancing scheduling accuracy and reducing

waiting time often used within building sites

Other tools such as Value Stream Mapping (VSM), Kaizen, and Total Quality Management (TQM) were rarely

implemented, reflecting a gap between awareness and comprehensive application.

These findings align with Ballard & Tommelein (2021), who asserted that JIT and 5S were easier to adopt due

to their simplicity and immediate impact. Conversely, tools like VSM and Pull Planning require more training

and cultural change, often lacking in Nairobi’s construction ecosystem (Nganga, 2020). [Zhang et al., 2021]

emphasized on stakeholder collaboration through Last Planner System (LPS) and Value engineering were

extensively used due to their effectiveness in reducing reworks and defects through collaborative planning.

Challenges in Implementation

Key barriers to the implementation of Lean practices within Nairobi City County was identified as Lack of

awareness and training rated as the most significant challenge to implementation. Unfamiliarity with lean tool,

Poor collaboration and communication, and resistance to change rated as significant challenges as well. High

initial implementation costs, Inadequate management support, lack of skilled personnel and limited resources

rated as moderately significant challenges. Cultural barriers ranked the lowest.

A Chi-square test of independence conducted indicated that lack of awareness/training, unfamiliarity with

tools, and poor collaboration were the most dominant challenges, consistent with findings by Olarewaju &

Abdul-Aziz (2020), who found awareness and training as the top barriers in Nigeria; as well as Alaloul et al.

(2020), whose study showed that limited collaboration and fragmented communication to be critical challenges

in implementing lean construction.

CONCLUSION AND RECOMMENDATIONS

The results revealed that Nairobi City’s construction industry is familiar with lean concepts, however, its worth

in waste management has not been fully leveraged. The data supports the assertion that lean construction, when

effectively implemented, can significantly reduce waste and subsequent inefficiencies on building sites. The

partial use of lean construction practices such as JIT delivery, 5S and value engineering already contributes to

more efficient practices. The research underscores the need for systemic and strategic interventions in training,

policy integration, and demonstration projects to bridge the current implementation gap.

Furthermore, this review establishes that while awareness of LC in Nairobi City County is relatively high,

practical implementation remains low.

To enhance the implementation of lean construction within construction building sites within Nairobi City

County the following recommendations can be taken up:

Capacity Building: Introduce continuous professional development (CPD) programs on LC.

Policy Integration: Mainstream LC practices into national construction codes and procurement guidelines.

Pilot Projects: Launch government-supported pilot lean projects to showcase benefits.

INTERNATIONAL JOURNAL OF RESEARCH AND SCIENTIFIC INNOVATION (IJRSI)

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Collaboration: Encourage partnerships between contractors, suppliers, and academia to localize lean practices.

The findings underscore the need for a coordinated approach to embed LC into Kenya’s construction industry,

ensuring improved efficiency, cost savings, and sustainability.

REFERENCES

1. Aigbavboa, C., & Thwala, W. D. (2019). Resistance to lean practices in the African

construction industry. Journal of Construction Research, 6(3), 124–135.

2. Alinaitwe, H., Mwakali, J., & Hansson, B. (2019). Assessing lean construction in Uganda.

Journal of Civil Engineering and Management, 25(4), 312–321.

3. Aziz, R. F., & Hafez, S. M. (2019). Applying lean thinking in construction and performance

improvement. Alexandria Engineering Journal, 58(2), 639–652.

4. Ajayi, S. O., & Oyedele, L. O. (2018). Critical design factors for minimising waste in

construction projects: A structural equation modelling approach. Resources, Conservation and

Recycling, 137, 302-313. https://doi.org/10.1016/j.resconrec.2018.05.022

5. Ayarkwa, J., Adinyira, E., & Osei-Asibey, D. (2020). Lean construction tools and techniques

in developing countries: A Ghanaian case study. Journal of Engineering, Design and

Technology, 18(6), 1283–1299. https://doi.org/10.1108/JEDT-09-2019-0243

6. Azhar, S., Ahmad, I., & Sein, M. K. (2013). Action research as a proactive research

methodology in the construction industry. Construction Management and Economics, 31(9),

705-718.

7. Ballard, G., & Howell, G. (2003). Lean project management. Building Research &

Information, 31(2), 119-133.

8. Ballard, G., & Howell, G. (2020). Lean construction: A guide to implementation. Routledge.

9. Jasti, N. V. K., & Kodali, R. (2014). Lean production: literature review and trends.

International Journal of Production Research, 53(3), 867–885.

https://doi.org/10.1080/00207543.2014.937508

10. Koskela, L. (1992). Application of the New Production Philosophy to Construction. CIFE

Technical Report No. 72.

11. Liker, J. K. 2004. The Toyota Way: 14 Management Principles from the World’s Greatest

Manufacturer. New York: McGraw-Hill.

12. Marhani, M. A., Jaapar, A., & Bari, N. A. (2019). Lean construction: Towards enhancing

sustainable construction in Malaysia. Construction Management and Economics, 37(6), 373-

392. https://doi.org/10.1080/01446193.2019.1566627

13. Nganga, P. (2020). The impact of lean construction on project efficiency in Nairobi. Journal of

Sustainable Construction, 12(1), 24-35.

14. Nguyen, P.; Akhavian, R. (2019) Synergistic effect of integrated project delivery, lean

construction, and building information modeling on project performance measures: A

quantitative and qualitative analysis. Adv. Civ. Eng., 1267048.

15. Ohno, T. 1988. The Toyota Production System: Beyond Large-scale Production. Portland, OR:

Productivity Press

16. Olanrewaju, A. L., & Abdul-Aziz, A. R. (2020). Organizational challenges to lean construction

implementation in Africa: A critical review. Journal of Construction in Developing Countries,

25(1), 89–108. https://doi.org/10.21315/jcdc2020.25.1.6

17. Sacks, R., Koskela, L., Dave, B. A., & Owen, R. (2020). Interaction of Lean and BIM in

Construction. Wiley.

18. Wachira, C. (2020). Lean construction: A case study of waste reduction in Nairobi construction

projects. Master’s Thesis, Kenyatta University.

19. Zhang, L., Chen, L., Liu, Y., & Song, Y. (2021). Integrated Project Delivery (IPD) and Last

Planner System (LPS) in large-scale hospital construction projects: A case study. Journal of

Cleaner Production, 278, 123948. https://doi.org/10.1016/j.jclepro.2020.123948