CHAPTER ONE

INTRODUCTION

1.1 Background of the Study

The construction industry plays a significant role in driving Nigeria's economic growth and development. However, the industry continues to encounter numerous challenges, including delays in project completion, cost overruns, low productivity, structural failures, unfair practices among contractors and consultants, and excessive dependence on foreign expertise and labour, among other problems (Dave et al., 2017).

Like many other developing nations, Nigeria regards the construction industry as a major contributor to its Gross Domestic Product (GDP). The industry influences economic activities, generates government revenue, stimulates investment, and provides employment opportunities for individuals with specialized skills and technical expertise (Steinhardt and Manley, 2016). Consequently, the construction industry remains an essential driver of economic development, particularly in developing economies such as Nigeria, where infrastructure and housing needs continue to expand (Bari et al., 2012).

Globalization has facilitated the exchange and transfer of information, knowledge, and technology among countries. Sustainable building materials and innovative construction approaches represent some of the technologies that have been adopted for many years in developed countries but are still emerging or developing in countries such as Nigeria (Zhu et al., 2018).

In the context of the construction industry, the term sustainable building materials is used in this study in connection with construction industrialization, prefabrication, and the adoption of innovative building components. These approaches involve the production of building components in controlled environments, either on-site or off-site, followed by their transportation, positioning, and assembly into a complete structure with minimal additional work at the construction site (Hamid et al., 2018). Such construction approaches may involve precast concrete components, fabricated steel structures, innovative formwork systems, modular block systems, and prefabricated timber structures (CIDB, 2013).

Under these methods, building components that are repetitive or difficult to produce on-site, or that require considerable time and labour, are designed as standardized units and manufactured in factories before being transported to the construction site for assembly. This approach can reduce the amount of conventional on-site casting and improve construction efficiency. Where casting activities are undertaken on-site, innovative and cleaner formwork technologies may also be employed (CIDB, 2017). The classification adopted by the Construction Industry Development Board (CIDB) is widely referenced by researchers and construction practitioners in discussions of industrialized and prefabricated construction.

Furthermore, the increasing demand for construction projects, particularly residential and commercial buildings, has encouraged renewed interest in prefabrication and other innovative construction approaches as alternatives to traditional building methods. These approaches have the potential to reduce labour requirements, construction costs, and project duration while improving the quality and durability of completed structures (Zhu et al., 2018). In Nigeria, one of the principal motivations for adopting these methods is to reduce dependence on foreign labour and minimize the loss of foreign exchange associated with imported construction expertise and resources (Ogunde et al., 2016).

The use of prefabricated building components may also reduce the consumption of certain construction materials, including cement, sand, timber, steel, and formwork, depending on the design and construction method employed. This reduction may result from more efficient material utilization and lower requirements for temporary framing and some foundation activities (Chiang et al., 2016). In addition, modern and innovative construction techniques are increasingly associated with sustainable construction practices. Their effective implementation can support a more balanced approach to construction by promoting resource efficiency, minimizing waste, and improving the environmental performance of buildings.

Despite these potential advantages, the adoption of sustainable and prefabricated construction methods is associated with several limitations. Chiang et al. (2016) identified challenges relating to the cost of establishing fabrication facilities, transportation, vertical movement of components on construction sites, workforce training, and difficulties associated with joining prefabricated components. Ogunde et al. (2016) similarly identified high initial construction costs as a major obstacle to the adoption of prefabricated construction in Nigeria. Xue et al. (2018) also observed that the construction industry has been slow to incorporate innovations such as automation, standardization, and modularization. Other barriers include inadequate awareness, unfavourable perceptions among designers and clients, and technical problems associated with component connections.

Several countries have introduced policies, programmes, and institutional initiatives to encourage the adoption of industrialized and sustainable construction methods. Rashidi and Ibrahim (2017) reported that various developed and developing countries introduced policies and established institutions between 1962 and 2015 to promote the implementation of such approaches.

In Asia, Malaysia introduced several construction development initiatives, including its Industrialized Building System Strategic Plan, the Construction Industry Master Plan, and subsequent roadmaps and transformation programmes. Singapore also introduced initiatives such as Construction 21 and Reinventing Construction, while Japan developed policy directions intended to improve the construction industry. In Europe, the United Kingdom introduced several initiatives aimed at integrating design and construction processes, improving industry performance, and encouraging off-site construction. Finland pursued the reengineering of construction processes through information and communication technology, while Ireland introduced programmes to strengthen collaboration and improve the construction sector.

Similarly, Australia developed initiatives to promote growth and innovation in construction, while the United States introduced national construction goals. In Africa, South Africa implemented programmes intended to create an enabling environment for reconstruction, growth, and development within the construction industry. Despite these initiatives and the implementation of industrialized construction projects in different countries, researchers have observed that the adoption of these methods has not fully matched the continued use of conventional construction approaches. This situation highlights the need to investigate the critical success factors required for the effective implementation of sustainable building materials and associated construction methods in Nigeria.

However, relatively few studies have provided comprehensive insights into the critical success factors influencing the implementation of prefabricated and industrialized construction projects in developing countries, particularly Nigeria. Omotayo and Keraminiyage (2014) examined differences in knowledge relating to lean construction and off-site construction techniques between Nigeria and the United Kingdom. Ogunde et al. (2016) investigated the challenges and factors influencing the use of prefabrication in Nigeria, while Ojoko et al. (2018) identified and assessed factors hindering the performance of industrialized construction methods in Nigerian mass-housing projects. In addition, Zakari et al. (2017) employed a mixed-methods approach to investigate the perceptions of construction professionals regarding the use of sustainable building materials and related construction approaches in Nigeria.

Building on the work of these researchers, particularly Ojoko et al. (2018), the present study examines the critical success factors influencing the implementation of sustainable building materials and associated construction methods in Nigeria.

Nigeria's population was estimated at approximately 186.9 million in 2016, alongside a reported housing deficit of about 17 million units. These demographic and housing challenges indicate the continuing need to develop affordable, sustainable, and durable housing, particularly low- and medium-income residential buildings. The country's growing population also creates increasing demand for roads, public facilities, commercial buildings, and other essential infrastructure. This demand is expected to continue as population growth and improvements in living standards increase the need for adequate infrastructure.

Meeting Nigeria's infrastructural and housing requirements within the framework of sustainable development requires the adoption of appropriate technologies, innovative construction methods, and efficient resource-management strategies. Although the prospects for implementing sustainable and industrialized construction approaches in Nigeria appear promising, considerable efforts are still required from government institutions, construction professionals, contractors, developers, and other stakeholders to encourage their widespread adoption.

Against this background, the present study focuses on assessing the impact of sustainable building materials on construction projects. It seeks to examine the level of knowledge of these materials and associated construction methods, identify the challenges affecting their implementation, and develop strategies for promoting their use to address Nigeria's housing and infrastructural needs.

1.2 Statement of the Problem

Although sustainable building materials and industrialized construction methods have long been promoted as alternatives capable of improving conventional construction practices, their adoption in Nigeria remains relatively limited. This situation may be attributed partly to inadequate awareness, insufficient coordination among relevant stakeholders, and differences in perceptions regarding their suitability and effectiveness. The level of utilization of prefabricated and industrialized construction methods remains low compared with conventional building approaches (CIDB, 2015). Despite their potential benefits, differing opinions among construction professionals, contractors, developers, and clients have contributed to the limited adoption of these methods.

The growing importance of sustainability has attracted considerable attention worldwide. Consequently, stakeholders in the construction industry, including local authorities, contractors, governments, consultants, and architects, are increasingly expected to respond to emerging environmental concerns and the need for more sustainable construction practices (Yang et al., 2015). Several studies have examined sustainability in the building and construction industry, highlighting its importance for environmental protection, resource efficiency, and improved construction performance (Cohen, 2016; Ding, 2018; San-José et al., 2017; Vanegas, 2013).

Nevertheless, Blismas et al. (2016) reported that the construction industry had not fully achieved the objectives established in the relevant industrialized construction roadmap, despite the implementation of many of its proposed activities. The mid-term review of the roadmap identified negative perceptions among consumers and construction practitioners as significant barriers to wider adoption. Even contractors with previous experience in prefabricated construction have sometimes been reluctant to apply the method to subsequent projects. This raises important questions about the factors responsible for the continued preference for conventional construction methods despite the potential advantages of industrialized alternatives.

Another major concern relates to the environmental consequences of conventional construction activities. Building construction requires the extraction, processing, transportation, and installation of materials such as concrete, timber, steel, and glass. These activities consume energy and can generate substantial greenhouse gas emissions, particularly in developing countries such as Nigeria, where fossil fuels remain an important source of energy for industrial and construction-related operations. The resulting emissions, including carbon dioxide and methane, contribute to global warming and climate change. Other pollutants may also be released during material production and construction activities, depending on the processes involved.

The extraction and consumption of construction materials also create environmental pressures. Some materials, including steel, glass, and cement-based products, require energy-intensive manufacturing processes and the extraction of finite or slowly replenished natural resources. Timber production can contribute to deforestation when trees are harvested without adequate replanting and sustainable forest-management practices. These activities may contribute to environmental degradation, desertification, desert encroachment, and disturbances in ecological systems. The loss of forest cover can also reduce the capacity of vegetation to absorb atmospheric carbon dioxide through photosynthesis.

In addition to environmental concerns, the construction industry faces economic and technical barriers that hinder the adoption of industrialized and prefabricated construction methods. The availability of relatively inexpensive unskilled labour may reduce the incentive for contractors to invest in more technologically advanced construction systems. High initial capital requirements, inadequate technical expertise, limited access to specialized facilities, and challenges associated with component transportation and installation may further discourage adoption (Blismas et al., 2016; Blismas and Wakefield, 2019; Chiang et al., 2016; Haron et al., 2019; Kamar et al., 2019). These constraints can encourage construction professionals to continue using conventional methods rather than transition to alternative approaches.

The persistence of these challenges raises concerns about the extent to which sustainable building materials and associated construction technologies can contribute to improved project performance in Nigeria. Although these approaches may offer benefits in terms of construction time, material efficiency, quality, and environmental performance, their effectiveness depends on the availability of appropriate resources, stakeholder awareness, technical competence, and supportive policies.

It is therefore necessary to assess the impact of sustainable building materials on construction projects, examine the factors limiting their implementation, and identify practical strategies for promoting their adoption in Nigeria. Addressing these issues may contribute to improved construction performance, more efficient resource utilization, reduced environmental impacts, and the delivery of affordable and sustainable housing and infrastructure.

1.3 Research Questions

The following research questions will guide the study:

1. What is the level of knowledge of sustainable building materials and associated construction methods within the Nigerian construction industry?

2. What challenges hinder the implementation of sustainable building materials and associated construction methods in the Nigerian construction industry?

3. What strategies can be adopted to promote the use of sustainable building materials and associated construction methods in the Nigerian construction industry?

1.4 Aim and Objectives of the Study

The main aim of this study is to assess the impact of sustainable building materials on construction projects.

The specific objectives are to:

1. Determine the level of knowledge of sustainable building materials and associated construction methods within the Nigerian construction industry.

2. Evaluate the challenges affecting the implementation of sustainable building materials and associated construction methods in the Nigerian construction industry.

3. Develop strategies for promoting the use of sustainable building materials and associated construction methods in the Nigerian construction industry.

1.5 Research Hypothesis

The following hypotheses are formulated for the study:

Null Hypothesis (H₀): There are no significant challenges affecting the implementation and use of sustainable building materials and associated construction methods in the Nigerian construction industry.

Alternative Hypothesis (H₁): There are significant challenges affecting the implementation and use of sustainable building materials and associated construction methods in the Nigerian construction industry.

1.6 Justification of the Study

This study is justified by the need to identify and promote improved approaches to housing construction in Nigeria. The construction industry continues to experience challenges relating to project duration, cost, quality, and safety. At the same time, the country faces considerable pressure to provide adequate housing for its growing population. These circumstances make it necessary to examine alternative construction methods that can improve project delivery and resource utilization. Sustainable building materials and industrialized construction approaches, including prefabrication, offer potential opportunities for addressing some of these challenges.

The study may also serve as a useful guide for property developers, contractors, and other construction professionals involved in future projects. By examining the application of sustainable building materials and related construction methods, the research may provide information that can assist stakeholders in making informed decisions about material selection, construction planning, resource allocation, and project implementation. Particular attention may be given to the effective management of construction time and resources.

Furthermore, the findings may help construction professionals identify suitable sequences of construction activities and approaches for improving resource utilization while minimizing unnecessary delays. Where applicable, the information obtained could support better coordination between the design, manufacturing, transportation, and assembly stages of industrialized construction projects. Such improvements may help reduce avoidable construction difficulties and enhance project performance.

The study is also expected to contribute to a broader understanding of the factors that influence the acceptance and adoption of sustainable building materials in Nigeria. By identifying the barriers to implementation and examining possible solutions, it may help stakeholders develop strategies for improving awareness, strengthening technical capacity, and encouraging investment in innovative construction technologies.

Ultimately, the study is intended to support the development and wider adoption of sustainable building materials and associated construction methods as viable alternatives within Nigeria's construction industry. Increased understanding of these approaches may contribute to more efficient construction practices and support efforts to meet the country's housing and infrastructural needs.

1.7 Scope of the Study

The scope of this study covers the construction industry, with particular emphasis on the application of sustainable building materials and associated construction methods in construction projects. The research examines the level of knowledge and awareness of these materials and methods among relevant construction stakeholders, the challenges affecting their implementation, and the strategies that could encourage their adoption.

The study also considers the potential implications of these construction approaches for project performance, including construction time, cost, quality, resource utilization, and environmental sustainability. Its central focus is to identify the most important factors influencing the successful application of sustainable building materials and to recommend measures for improving their use in the construction industry.