Barriers to sustainable procurement in the Nigerian construction industry: an exploratory factor analysis

Abstract

Research into the application of sustainable procurement in construction projects is nascent with the few prominent studies carried out in the developed nations. Of particular interest is how developing nations are rising to the challenge of development and using their procurements strategically. One way the construction industry helps to achieve sustainable development is through its procurement activities. Previous studies show that Nigeria is embracing sustainable procurement however the uptake is slow. Therefore, this research sets out to evaluate the factors that constitute barriers to sustainable procurement of publicly funded construction projects in Nigeria. A questionnaire survey was used to evaluate construction industry professionals' perspective on the barriers to sustainable procurement in Nigeria. Three hundred and twenty questionnaires were returned and used for analysis. Out of the nineteen variables tested, factor analysis reveals four clusters named in other of significance as sustainability knowledge level, transparency and governance, mismatch of procurement strategy and national policy challenges, and construction industry related factors. This study recommends that mitigating these challenges will require improving sustainability knowledge among project stakeholders, ensuring transparency and good governance, adapting procurement laws with sustainability clauses and construction industry development.

Keywords:

• Barriers
• construction industry
• factor analysis
• procurement
• sustainable

1. Introduction

Nations are using their position as volume buyers to influence the thrust of their procurement policies to encompass social and environmental dimensions (Renukappa et al. 2016, 19). Existing studies confirm that the construction industry plays a vital role in the adoption of sustainable procurement practices towards attaining the sustainable development goals (Rwelamila et al. 2000; PricewaterhouseCoopers 2009; Varnäs, Balfors and Faith-Ell 2009; Kahlenborn et al. 2011; Renda et al. 2012). However, there is paucity of empirical research on how the construction sector is addressing sustainable procurement issues (environmental, social and economic) in their whole supply chain, most especially in a developing nation's context. Studies in Nigeria have attempted to give an insight into how the public sector and the construction industry, in particular, fairs as regards sustainable procurement (Olanrewaju et al. 2014; Ogunsanya et al. 2016; Faremi et al. 2017). These studies conclude that sustainability adoption is low. Furthermore, Adebayo (2015) contends empirically that there are inadequate policy mechanisms to embed sustainability in public procurements in Nigeria. It is therefore pertinent to unravel the causes of low uptake or lack of implementation of sustainable procurement in the construction industry seeing that the government has committed to the sustainable development agenda. The current study seeks to identify the barriers to sustainable procurement of publicly funded construction projects in Nigeria and see if the barrier factors can be further grouped into closely related components.

2. Sustainable procurement and the Nigerian construction industry

Sustainable procurement (SP) was first muted as a concept in the United Nations World Summit on Sustainable Development in 2002 in Johannesburg. However, the idea has its footing in the mid-1990s as green procurement (United Nations 2016). The initial thrust of the green procurement movement entails coupling environmental criteria into product’s requirements. This agenda has grown and widened to include social performance and new economic goals. The concept of sustainable procurement draws attention to the responsibility of a company for activities outside its boundaries (Meehan and Bryde 2011; Association for Project Management 2016). According to the Chartered Institute of Purchasing and Supply (2011), it entails socially and ethically responsible purchasing, environmental impact minimization through the supply chain, and adopting economically sound solutions, all entrenched in a good business framework. It is believed that sustainable procurement saves cost and reduces waste by questioning the need to buy, reducing quantities where necessary, saving energy and water, promoting re-use and recycling, minimizing packaging and increasing transport efficiencies. Sustainable procurement actions in the United Kingdom (UK) are based on the Flexible Framework Model and the BS 8903: 2010 which entails principles and framework for procuring responsibly. Furthermore, Walker and Brammer (2009) argue that the concept of sustainable procurement is consistent with the principles of sustainable development, which imply ensuring that societies develop healthily with genuine concern for human and plant life, considering environmental limits and good governance, while achieving the former through purchasing and the supply process.

Mensah and Ameyaw (2012, p. 872) assert that traditional procurement entails the quest for value for money while sustainable procurement is about value for money on a whole life cycle basis considering the economic, social and environmental dimensions. Greener (2008) posits that sustainable procurement is the application of sustainable development principles to procurement and this is crucial in helping to achieve a world that is habitable, affording people a good quality of life. Taking a cue from the works of Berry and McCarthy (2011) and Roos (2012), the four cardinal aims of sustainable procurement can be expressed as minimization of the impact of procured items (goods, services and works) across the life cycle by supply chains; reducing resource use through optimization of purchases, using resource-efficient products, re-use and recycling of products; using fair contract prices and terms while upholding utmost ethical standards, human rights protection and employment standards; and promoting equality and diversity through the supply chain (Berry and McCarthy, 2011; Roos 2012). Researchers identify the drivers of sustainable procurement are: compliance with legislation; technology and innovation; organisational structure and processes; education and training; political willingness; adoption of global strategy; knowledge of sustainable procurement; legal framework; monitoring; market demand, government policy, reputation, and customer requirements. While for the construction industry, the drivers are: value for money, reputation, market differentiation, capabilities and culture, category management and execution, structures and systems, and integration and alignment.to mention a few (Walker and Brammer, 2009; Belfitt et al. 2011; United Nations Environmental Programme, 2016) and Spiller, Reinecke, Ungerman and Teixeira, 2012).

Also, few studies have considered international variations in the engagement of public bodies with sustainable procurement. Considering the scale and importance of public procurement, and the capacity for sustainable public procurement to bring about social benefits directly and by modifying the activities of private sector organisations, it is necessary to explore how effective policy initiatives have been encouraging public organisations to purchase sustainably (McCrudden, 2004; Weiss and Thurbon, 2006).

The construction industry generally comprises of organisations and persons concerned with the process by which building and civil engineering works are procured, produced, altered, repaired, maintained and demolished. These include companies, firms and individuals working as consultants, contractors and subcontractors, material producers, equipment suppliers and builders’ merchants (Hillebrandt 2000; Construction Industry Development Board 2015). The industry works harmoniously with clients, financiers and other stakeholders. The Nigerian construction industry has as its main players construction firms ranging from the small, medium and micro enterprises to the multinational construction firms. Government is the largest client of the industry, though in recent years there is increased patronage from private sector clients (Mbamali and Okotie 2012). The Nigerian population continues to increase faster than the rate at which public infrastructure is provided. This infrastructure deficit has since continued. Consequently, some indigenous construction companies were established to tap into the emerging opportunities.

Furthermore, the construction sector has been a contributor to the GDP of Nigeria (Omole, 2000). This it has continued to do in a progressive manner considering the level of infrastructure need in the nation. The real GDP for the country for 2010 was N54.612 trillion. The construction sector’s contribution was N1.570 trillion. This implies a share of 2.88%. The construction sector grew by 21.30% to reach N1.905 trillion in 2011. A gradual reduction in the growth rate of the construction sector by 14.86% resulted in the sector closing at N2.188 trillion in 2012 (National Bureau of Statistics 2015). The sector also serves as a current and potential employer of the teaming unemployed youths in the country. The construction industry has provided over 6 million construction-related employment opportunities to both Nigerian and non-Nigerian professionals.

Despite the success of the construction sector through the Infrastructure Concession and Regulatory Commission (ICRC) reform policy, key industry players have mixed views on its wholesomeness in achieving the intended goals (ICRC 2012; National Planning Commission 2015). For instance, Ozoigbo and Chukuezi (2011) and Idoro (2010) argue that there are significant inequalities between economic growth and subsequent development in the Nigerian construction sector. The reform policy is viewed to confer some privileges on multinationals through outsourcing of materials and human resources with no due justifications. Critics of the practice are concerned about the implications of continued marginalisation of local skills and manufacturing sectors.

Furthermore, the clamour by stakeholders for sustainable development in Nigeria is relatively recent. The Nigerian Government took a giant step towards sustainability in 2007 when it established Nigerian Environmental Standards and Regulatory Enforcement Act (NESREA Act) and the Agency (NESREA 2007). The agency has domesticated Agenda 21 Nigeria. The principal goal was to integrate environmental dimensions into development planning at Federal, state and local government levels, to start the transition to sustainable development while addressing sectorial priorities, plans and strategies for implementation, and using the collaboration of regional and global resources. The direct implications of this is that it has become mandatory for environmental impact assessment to be undertaken before construction of public facilities, remedial measures are taken to reduce the impact of construction, and the initiation of post construction review audits (NESREA 2017). In the same year, the Public Procurement Act (PPA 2007) was passed and the Bureau of Public Procurement was established. This other agency focuses on the financial proprieties of acquisition of public goods, works and services. Ensuring value for money, accountability, transparency and respect for public thrust is maintained in transactions. Despite the aforementioned, Nigeria is lagging world developments associated with sustainability within the construction sector and beyond. There is currently no legislation requiring that a sustainable procurement policy should be applied to projects of particular magnitude and worth in Nigeria.

3. Barriers to sustainable procurement

Brammer and Walker (2011) identified the barriers to sustainable procurement as financial, informational, legal, managerial/structural, political/cultural and product quality priority. Similarly, despite the advantages for the adoption of sustainable procurement at the organisational level, the following factors by Meehan and Bryde, (2011) were considered critical barriers to its uptake. First is ‘inertia’ within the company. Inertia develops from the institutionalisation of a routine within an organisation. As firms try to maintain a sense of reliability, processes become routine. Thus, the implementation of changes become more difficult, as it will be an upheaval to the existing routine (Meehan and Bryde, 2011, Belfitt et al., 2011). Another is the conflict of incentives. The procurement staff could feel pressured to make decisions that do not align with sustainable procurement strategy. This could indicate that there is a conflict between the pressures on staff and the greater driving them towards maintaining, the more traditional approach. The third barrier relates to a meaningless formality. Even though many companies are documenting sustainable procurement strategies in their annual reports, it would be interesting to find out to what extent these policies influence the procurement decisions within a company. Another possible barrier is that those who are going to benefit from sustainable procurement adoption on construction projects are not the persons bearing the cost. When the cost of maintenance is considered it may seem a bit far-fetched from the contractor that builds the facility, except when build-operate-transfer or build-operate-own-transfer models are used. Likewise, some argue against the appropriateness of making the initial occupants of a building pay for end of life costs that are many years away from the initial occupants (Belfitt et al., 2011).

According to the Sustainable Development Commission (2004), the commonly cited hindrances to sustainable procurement are: perception that it increases cost, lack of awareness of the need for sustainable procurement and the processes entailed, lack of knowledge required, risk averseness on the part of clients, legal constraints, leadership challenges and inertia. Similarly, Meehan and Bryde (2011), posits that a major barrier to the adoption of sustainability in procurement is the lack of engagement with suppliers. Another barrier is the fact that some of the supply chains are multinational while the laws regulating sustainability or sustainable procurement are national or locally formulated. This dichotomy is a challenge.

Within a developing nation’s context, Mensah and Ameyaw (2012: 874) argue that the following barriers must be surmounted to attain sustainable procurement in a developing nation using Ghana as a case study. These are: the absence of internal management structures that support sustainable procurement; lack of social drive from major stakeholders; low technical and management capacity; an inefficient approach to stakeholders' management; the high initial cost of green products; low stakeholders' education; the absence of government interest; lack of political will; corruption among procurement practitioners; lack of capacity for small scale suppliers and contractors (Mensah and Ameyaw, 2012, p. 874). The main findings of the research is that the lack of understanding of sustainable procurements and the higher initial cost associated with sustainable procurement are the most significant hindrances to sustainable procurements in Ghana. Ross (2012:53) found the barriers in another developing nation’s context as legal framework that does not encourage sustainable public procurement (SPP), donor guidelines that does not encourage SPP, lack of capacity, lack of guidance materials and practical tools, complexity of SPP, expectation of increased cost, and inflexible budgetary mechanism. In Malaysia, McMurray, Islam, Siwar and Fien (2013) found that religion significantly influences the decision of procurement managers in the private sector and directors in the public sectors. They identified major barriers as lack of awareness, lack of resources, lack of a long-term view to procurement decisions, lack of guidance and lack of political support when sustainable procurement practices were compared between the public and private organizations. However, Ruparathna and Hewage (2015) established in a Canadian study that lack of consideration of sustainability criteria in bid evaluation topped the list when drawbacks to sustainable procurement were considered. Others are the unavailability of standard methods for procurement and lack of knowledge of local conditions. According to the United Nations (2016), barriers to sustainable procurements are habit and the difficulty in changing procurement behaviour; lack of suppliers of sustainable assets, suppliers or services; complexity of comparing costing/value for money assessments; the difficulty of including factors broader than environmental considerations; and a perception that the process and outcomes are costlier or time-consuming. Although there are clear advantages for a company's adopting sustainable procurement procedures, these have not been largely realised. For instance, in the UK uptake of whole life costing in the private sector is still below 10% (Renukappa et al. 2016). The identified barriers from the literature above and knowledge of the Nigerian environment helped to form the critical mass of the indicator variables tested further in the study. The variables used in the study are listed is Table 1.

Table 1. Definition of potential barriers factors for sustainable procurement.

Variable no	Variable Name
HSP01	Lack of awareness of sustainability concepts
HSP02	Reluctance of the contractor side to adopt sustainability practices in procurement
HSP03	Lack of motivation for the implementation staff
HSP04	Lack of capacity in required human resources
HSP05	Perceived high cost of adopting sustainable solutions
HSP06	Failure to match project needs to procurement options
HSP07	Failure of Government to establish National Council for Public Procurement
HSP08	Lack of commitment to National Development Plan
HSP09	Inadequate time for the pre-contract phase
HSP10	Lack of regulatory framework for sustainable construction procurement
HSP11	Lack of enforcement and implementation of relevant laws
HSP12	Lack of monitoring and control on projects
HSP13	Corruption
HSP14	Political interference
HSP15	Non availability of sustainable materials
HSP16	Failure to adhere to quality management processes
HSP17	Reluctance in embracing new knowledge
HSP18	Lack of confidence in local contractors
HSP19	Delays in payment of contractors

Sources: (Belfitt et al., 2011; Meehan and Bryde, 2011; Mensah and Ameyaw, 2012: 874; McMurray et al. 2013; Olanrewaju, et al. 2014; Ruparathna and Hewage, 2015; Ogunsanya, et al. 2016; Renukappa et al. 2016; Faremi, et al. 2017; United Nations, 2017).

All the studies above have evaluated hindrances to sustainable procurement within different national contexts and industry sectors; it is, therefore, essential to identify the barriers to sustainable procurement of publicly funded construction projects in Nigeria. This study adopts a quantitative research approach as its methodology which is explained hereafter.

4. Methodology

This study uses a quantitative approach to identify the most critical barriers/hindrances to sustainable procurement in the Nigerian construction industry. The choice of research methodology was determined by the ontological and epistemological basis of the investigation and position of literature (Creswell, 2009; Bryman, 2012). Therefore it uses a survey method to investigate the phenomenon of interest in the study population. The survey entails administering questionnaires to willing participants carefully selected. The population of interest in this research are practitioners and professionals involved in the procurement of publicly funded construction projects in Nigeria. Simple random sampling was used to identify professionals in three major states of the country (Lagos, Ogun and the Federal Capital Territory – Abuja). The choice of the locations was due to the volume of construction projects that are publicly funded in these locations (Lagos, Abuja) while Ogun state represents an emerging business hub. Out of the 602 questionnaires that were administered which comprise personally administered questionnaires and copies sent through electronic mail, only 320 responses were useful for analysis at the close of the survey (53.2%). From the total number of respondents (N = 320), 35% (n = 111) work in Abuja, 34.1% (n = 108) work in Lagos State, 30.3% (n = 96) work in Ogun State while the remaining 0.6% work outside the main states of interest as shown in Table 2. The main survey locations critical to the study were Abuja, Lagos, and the Ogun States. Other demographic details of the respondents are indicated in Table 2. The researcher obtained the consent of the participants regarding their willingness to partake in the study and were informed it is part of ongoing doctoral research aimed at developing a sustainable procurement model for the Nigerian construction industry.

Table 2. Respondents’ demographic characteristics.

Demographic characteristics	Percentage	n
Gender
Male	79.7	255
Female	20.3	65
Age
21–25	2.5	8
26–30	9.4	30
31–35	12.9	41
36–40	13.5	43
41–45	22.3	71
46–50	18.2	58
51–55	13.2	42
56–60	7.5	24
61–65	0.3	1
Highest qualification
National Diploma	1.9	6
Higher National Diploma	21.5	68
Bachelor’s degree	51.4	163
Master’s degree	24.3	77
Doctorate	0.9	3
Professional qualification
Architect	17.7	56
Builder	12.6	40
Civil engineer	30.6	97
Electrical engineer	6.3	20
Mechanical engineer	5.0	16
Structural engineer	3.2	10
Procurement officer	5.0	16
Quantity surveyor	18.0	57
Project manager	1.6	5
Years of Experience in the Construction Industry
1–5	16.5	52
6–10	21.2	67
11–15	19.0	60
16–20	19.6	62
20–25	13.0	41
26–30	7.3	23
Above 30	3.5	11
Sector of the Construction Industry
Government agency	53.6	171
Contractor	18.2	58
Consultant	14.4	46
Other: private	13.8	44

5. Data analysis

5.1. Factor analysis

According to Pallant (2013:181), Factor analysis is a data reduction and analysis method. Also, Tabachnick and Fidell (2007) argue that factor analysis produces a theoretical solution untainted by unique and error variability. Thus, there are two main approaches to factor analysis (exploratory factor analysis and confirmatory factor analysis). The exploratory factor analysis is used to elicit information regarding interrelationships among a set a variables while confirmatory factor analysis is used later in the research process, entailing complex and more sophisticated techniques in testing specific hypotheses relating to the structural relationships of variables. However, this study makes use of exploratory factor analysis for this paper.

5.2. Stages in exploratory factor analysis

There are 3 stages in conducting exploratory factor analysis. These are;

Assessment of suitability of data. The two prominent conditions that must be satisfied in terms of suitability of data are sample size adequacy and strength of correlation amongst the variables. Several authors hold different position as regards sample size adequacy, though there is a consensus that the larger the sample size the better. Pallant (2013) holds that the size should be at least 300 cases while Tabachnick and Fidell (2007) support 150 cases. Also, on the strength of interrelationships of the variables, it is recommended that the correlation matrix should be inspected for coefficient values greater than 0.3. If larger percentage is greater than 0.3 the sample is adequate but if there are very few correlation coefficients greater 0.3 the sample is inadequate. Two tests used to confirm for the conditions above are the Kaiser-Meyer-Olkin (KMO) measure of sampling adequacy and the Bartlett’s test of sphericity.

Factor extraction. This process entails identifying minimum number of factors that can be used to represent interrelationships of a set of variables. The major techniques for factor extraction are principal component, principal factors, image factoring, maximum likelihood factoring, unweighted least squares, and generalized least squares. The commonly used technique is the principal component analysis. This technique involves balancing the need for a simple solution with the minimum factors needed to explain so much variance in the original data set. The principal component analysis can be effected as Kaiser’s criterion, scree test or parallel analysis. The current study uses a scree test which is generated by plotting all the eigenvalues of the factors.

Factor rotation and interpretation. The process of rotation helps in providing clearer picture of the components generated without altering the underlying solutions. Thus, SPSS present the components as clusters of variables which the researcher uses the base theory and past researches to interpret. There are more than one technique to effect factor rotations. These are varimax, quartimax and equamax used when orthogonal rotations are desired while oblique rotations are effected by direct oblium and promax techniques. The current study used varimax technique.

5.3. Assumptions for exploratory factor analysis

Factor analysis is deemed appropriate when the Kaiser-Meyer-Olkine (KMO), the measure of sampling adequacy test index, is higher than the satisfactory minimum limit of 0.5 and a desirable limit of 0.8 or greater (Kaiser, 1970). Conventionally, a Cronbach’s alpha of 0.70 is considered reasonably good for the scale reliability and internal consistency of the instrument (Field, 2009; Hair et al. 2010). Also, suggested a cut-off value KMO greater than or equal to 0.70. According to Hair et al. (2010), Bartlett’s test with a significance level of less than 0.05 substantiates the appropriateness of the factor model. The import of this is that there are potential correlations among the variables and thus indicative of a reasonable potential cluster forming factors from the variables (Field 2009; Hair et al. 2013).

Furthermore, eigenvalues greater than 1 were considered significant and were used to explain the variance obtained by a factor. According to Hair et al. (2010), eigenvalues of less than 1 are considered insignificant: these were excluded accordingly in the current study. Before conducting the principal component analysis, communalities extracted on each variable were assessed and presented. The communalities are critical and useful in deciding the variables that have to be finally extracted (Field 2009). This is because by connotation, the communalities typify the total amount an original variable shares with all other variables included in the factor analysis (Field 2009; Hair et al. 2013). According to Field (2009) and Motulsky (2015), an average communality of the variables after extraction should be above 0.60 to support reliable results and interpretations in factor analysis. Also, the conventional rule about communality values in factor analysis suggests that a potentially significant variable must yield an extraction value (eigenvalues) greater than 0.50 at the initial iteration (Field 2009; Hair et al. 2013).

Factor analysis was used to establish which of the variables could be measuring the same underlying effects so that they can be grouped together. The data was screened for completeness and to ensure that missing values and incomplete data sets did not affect the analysis. As will be observed, there are more than 320 data set (i.e. >150 cases), which is sufficient for factor analysis. The analysis, findings and the discussion are as follows.

5.4. Exploratory factor analysis of barriers to sustainable procurement

Nineteen items evaluating hindrances to sustainable procurement were subjected to principal component analysis using SPSS version 22. Before this, the suitability of data for analysis was assessed. Inspection of the correlation matrix showed many of the coefficients had values of 0.3 and above. The Kaiser-Meyer-Olkin (KMO) measure of sampling adequacy of 0.893 was obtained. This value is above the desirable value of 0.8. From Table 3, Bartlett’s test of sphericity was 2575.429 with an associated significance of 0.000. Also, a Cronbach’s alpha of 0.913 was realized, suggesting an acceptable level of internal consistency and reliability in the measures and the scale.

Table 3. KMO and Bartlett’s test.

Kaiser-Meyer-Olkin Measure of Sampling Adequacy.		0.893
Bartlett's Test of Sphericity	Approx. Chi-Square	2757.429
	Df	171
	Sig.	0.000

a. Cronbach’s alpha = 0.913.

From Table 4, the average communality of the variables after extraction was 0.632. Hence, the communalities extracted support the use of factor analysis on the variables. It can be observed that no item had extracted eigenvalues less than the 0.50 cut-off point, hence all the variables a qualified for further analysis (Field 2009; Hair et al. 2013). Similarly, the rotated component matrix in Table 5 showed four distinct components as each variable dominantly belonged to a unique factor (component). From this result, the components that emerged could be the dominant underlining factors determining barriers to sustainable procurement.

Table 4. Communalities.

Communalities
	Initial	Extraction
HSP01 Lack of awareness of sustainability concepts	1.000	0.713
HSP02 Reluctance of the contractor side to adopt sustainability practices in procurement	1.000	0.712
HSP03 Lack of motivation for the implementation staff	1.000	0.680
HSP04 Lack of capacity in required human resources	1.000	0.684
HSP05 Perceived high cost of adopting sustainable solutions	1.000	0.564
HSP06 Failure to match project needs to procurement options	1.000	0.702
HSP07 Failure of government to establish National Council for Public Procurement	1.000	0.655
HSP08 Lack of commitment to the National Development Plan	1.000	0.609
HSP09 Inadequate time for the pre-contract phase	1.000	0.403
HSP10 Lack of regulatory framework for sustainable construction procurement	1.000	0.638
HSP11 Lack of enforcement and implementation of relevant laws	1.000	0.677
HSP12 Lack of monitoring and control of projects	1.000	0.685
HSP13 Corruption	1.000	0.768
HSP14 Political interference	1.000	0.572
HSP15 Non-availability of sustainable materials	1.000	0.606
HSP16 Failure to adhere to quality management processes	1.000	0.613
HSP17 Reluctance in embracing new knowledge	1.000	0.667
HSP18 Lack of confidence in local contractors	1.000	0.682
HSP19 Delays in payment of contractors	1.000	0.544

Extraction Method: Principal Component Analysis.

Table 5. Rotated component matrix.

	Component
	1	2	3	4
HSP01 Lack of awareness of sustainability concepts	0.802
HSP03 Lack of motivation for the implementation staff	0.770
HSP04 Lack of capacity in required human resources	0.768
HSP02 Reluctance of the contractor side to adopt sustainability practices in procurement	0.761
HSP09 Inadequate time for the pre-contract phase	0.501
HSP13 Corruption		0.833
HSP14 Political interference		0.704
HSP11 Lack of enforcement relevant laws		0.645
HSP12 Lack of monitoring and control of projects		0.641
HSP10 Lack of regulatory framework for sustainable construction procurement		0.559
HSP06 Failure to match project needs to procurement options			0.807
HSP07 Failure of government to establish National Council for Public Procurement			0.766
HSP05 Perceived high cost of adopting sustainable solutions			0.693
HSP08 Lack of commitment to the National Development Plan			0.621
HSP18 Lack of confidence in local contractors				0.790
HSP17 Reluctance in embracing new knowledge				0.753
HSP16 Failure to adhere to quality management processes				0.622
HSP15 Non-availability of sustainable materials				0.621
HSP19 Delays in payment of contractors				0.594

Extraction Method: Principal Component Analysis. Rotation Method: Varimax with Kaiser Normalization.

Rotation converged in 7 iterations.

From the result presented in Table 6, a four-factor component solution which explained a total of 64.076% of the variance was obtained. The first component explained 39.868% of the variance; the second component explained 9.496%; while the third component 8.484%; and the last component 6.226%. The total variance explained is above the recommended minimum of 50% (Field, 2009; Pallant, 2013; Motulsky, 2015). The four components were named according to the factor with the highest loading in the cluster. These are explained in greater details in the discussion section. Also, the scree plot for the factor analysis is shown in figure 1.

Table 6. Total variance explained.

Component	Initial eigenvalues			Extraction sums of squared loadings			Rotation sums of squared loadings
	Total	% of Variance	Cumulative %	Total	% of Variance	Cumulative %	Total	% of Variance	Cumulative %
1	7.575	39.868	39.868	7.575	39.868	39.868	3.654	19.232	19.232
2	1.804	9.496	49.363	1.804	9.496	49.363	2.941	15.481	34.713
3	1.612	8.484	57.847	1.612	8.484	57.847	2.872	15.116	49.829
4	1.184	6.229	64.076	1.184	6.229	64.076	2.707	14.247	64.076
5	0.905	4.765	68.841
6	0.821	4.319	73.160
7	0.740	3.893	77.054
8	0.612	3.221	80.274
9	0.527	2.776	83.050
10	0.460	2.419	85.470
11	0.423	2.227	87.696
12	0.380	2.000	89.697
13	0.348	1.829	91.526
14	0.327	1.722	93.248
15	0.309	1.628	94.876
16	0.281	1.477	96.353
17	0.261	1.373	97.726
18	0.234	1.231	98.956
19	0.198	1.044	100.000

Extraction Method: Principal Component Analysis.

Figure 1. Scree plot for factor analysis.

6. Discussion of results

6.1. Component 1 – sustainability knowledge level

The five barrier factors extracted for component 1 were Lack of awareness of sustainability concepts (80.2%), Lack of motivation for the implementation staff (77.0%), Lack of capacity in required human resources (76.8%), Reluctance of the contractor side to adopt sustainability practices in procurement (76.1%), Inadequate time for pre-contract phase (50.1%). The numbers in parenthesis are the factor loadings. This cluster accounted for 39.868% of the variance (Table 6). This cluster shares in common the general link to sustainability knowledge and awareness and capacity on the contractor side. Olanrewaju et al. (2014) argue these are the bane of the Nigerian construction industry as regards sustainability. The authors claim that the awareness level of sustainable construction among industry practitioner is moderate for the majority of the survey respondents. Also, Berry and McCarthy (2011) assert that there should be a sustainability agenda on every project, most especially public infrastructure that is well articulated. Thus, procurement sustainability requirements must be contractually enforceable where possible. Projects must have established standards and measurements such that non-compliance can be identified and corrected in the course of execution. If this is not done, it will be difficult for the contractors to implement sustainability in procurement. The design team must work with this mindset and specify sustainable materials (energy efficient, long-lasting, cost-effective and easily disposed at the end of life). Also, Meehan and Bryde (2011) advocate genuine engagement not only with the contractor but the entire supply chain side while Adebayo (2015) shows that there are inadequate policy mechanisms to embed sustainability in public procurements in Nigeria. Similarly, the perspective of Ross (2012) is instructive, who contends that there is a general lack of competence in sustainability matters in developing nations. This incompetence manifests as a lack of practical tools, information and training noting that for several public entities, including environmental and social requirements into their procurement functions is a new concept. Marrakech Taskforce report shows the same deficiency and has started preliminary works in terms of pilot projects in 13 countries to foster the promotion of sustainable public procurement (UNEP 2012). The traditional position is that projects are delivered the way the client wants it. Lately, contractors have begun to offer sustainable solutions as value offerings to the client. So, request for sustainability on projects doesn't have to be at the instance of the client alone.

6.2. Component 2 – transparency and governance

The five barrier factors extracted for Component 2 were Corruption (83.3%), Political interference (70.4), Lack of enforcement of relevant laws(64.5%), Lack of monitoring and control on projects (64.1%), Lack of regulatory framework for sustainable construction procurement (55.9). This cluster accounts for 9.496% of the variance (Table 6). The numbers in parenthesis are the factor loadings. UNODC (2019) claims that up to 20-25% of the procurement budget is drained through corruption globally. Eyo (2017) in a review of the impact of corruption on sustainable public procurement in Africa found that at the macro level, entrenched corruption depletes the limited funds available for public spending and proposes stronger control systems at the micro/institutional levels to mitigate the actions of corrupt public officials. The reorganization of the public procurement system in Nigeria and Public Procurement Act (PPA) promulgation was to provide some of the controls that Eyo (2017) suggested. Also, anti-corruption agencies such as Economic and Financial Crimes Commission (EFCC) and Independent Corrupt Practices and related Offences Commission (ICPC) were created to address issues arising from infractions of public procurement amongst others in Nigeria. Furthermore, when contract values are inflated to almost 4times the cost of the project, value for money on a whole life cycle basis is truncated. Also, the existing regulation (PPA 2007) is generally for goods, works and services with no direct provisions for sustainability. However, Williams-Elegbe (2012) argues that the PPA falls short in international best practices on transparency by not specifying which threshold performance bond is required, giving great discretionary powers to procuring authorities regarding procurement decisions which is subject to abuse, and does not mandate procuring authorities to inform unsuccessful bidders why they lost except an official inquiry is made. At the national level, Roos (2012, p. 51) contends that developing nations may need to modify their legislation to be able to incorporate sustainability criteria. Ogunsanya (2018) advocates for sustainable procurement act that focuses on construction and infrastructure projects considering the share of the national budget that these constitute in Nigeria. Furthermore, Gelderman, Semeijn and Bouma, (2015) argue that political leaders are less likely to promote sustainable procurement just as this study affirms.

6.3. Component 3 – mismatch of procurement strategy and national policy challenges

The 4 barrier factors extracted for Component 3 were Failure to match project needs to procurement options (80.7%), Failure of government to establish National Council for Public Procurement (76.6%), Perceived high cost of adopting sustainable solutions (69.3%), and Lack of commitment to National Development Plan (62.1%). This cluster accounts for (8.484%) of the variance (Table 6). The numbers in parenthesis are the factor loadings. At the project level, the inability of the project sponsors to identify the most appropriate procurement method to use can frustrate project sustainability (Rwelamila, Talukhaba, and Ngowi, 2000). Several procurement methods exist with newer ones being developed to correct some the challenges of the past (Babatunde, Opawole and Ujaddugbe, 2010). Also, the perceived high cost of implementing a sustainable solution is another barrier. This is taking a short term view of the sustainable procurement benefit. If a long term perspective is considered and the present-future cost/benefits are balanced sustainable procurement is cheaper on the long run. The reality is that sustainability and sustainable procurement goes beyond the environment, there are issues of health and safety of employees, appropriateness of their wages and working conditions, use of locally available substitutes among others and best value for money.

6.4. Component 4 – construction industry related

The 5 barrier factors extracted from Component 4 were Lack of confidence in local contractors (79%), Reluctance in embracing new knowledge (75.3%), Failure to adhere to quality management processes (62.2%), Non-availability of sustainable materials (62.1%) and Delays in payment of contractors (59.4%). This cluster accounts for 6.226% of the variance. For the construction industry to fully engage with sustainable procurement, there is industry readiness that is required, and the identified challenges have plagued the industry in the past. Ozoigbo and Chukuezi (2011) and Idoro (2010) raised questions about continual marginalisation of local skills and the manufacturing sector. Previous studies used the experiences in Singapore, Malaysia and Australia to establish that the participation of local contractors and small and medium scale suppliers are crucial to construction industry development. Further, Ofori (2016) justifies how project team integration, promotion of health and safety, engagement with stakeholders, effective project governance, effective post-project reviews and the adaptation of novel ideas that have worked in other climes can positively impact on the growth of construction industry in developing nations. There is a need for development in the construction industry in Nigeria if the sector will effectively utilise and realise the benefits of sustainable procurement (Faremi et al. 2017). Some of the new initiatives are contractor development, contractors’ classification, construction (SMEs) empowerment through subcontracts, financial assistance to contractors with valid contracts, middle level manpower skills development, materials supply chain management, research into alternative sustainable materials, collaboration between educational institutions, professional bodies, government and financial institutions, creation of construction industry development board (Chukwudi and Tobechukwu, 2014; Ogunsanya, 2018).

7. Conclusion and recommendation

The barriers to sustainable procurement are diverse as different factors are responsible. Though the benefits of sustainable procurement in the delivery of construction projects are known. There is paucity of knowledge as to the factors that are mitigating against sustainable procurements in the Nigerian construction industry. Hence, through a survey of construction industry professionals, the barriers to sustainable procurement were classified into 4 clusters. These are; sustainability knowledge factors, transparency and governance factors, mismatch of procurement strategy and national policy issues; and construction industry development related factors. These findings lend support and align with the findings of studies in Ghana. It is therefore recommended that efforts should be intensified on awareness creation and capacity development of construction industry professionals on integrating sustainability in the procurement processes, thus leading to increase in adoption of sustainable procurement. Currently, there is no law requiring that sustainable procurement should be used to guide procurement of public assets in Nigeria. There is a need to make such a law.

Future studies should focus on how the drivers of sustainable procurement can be used to overcome these barriers. This study also provides input into requirements for developing a sustainable procurement model for the Nigerian construction industry.

Acknowledgements

The authors acknowledge the participants who took part in the survey and the panel of reviewers for this article in ensuring that it comes out in its best form.

Disclosure statement

No conflict of interest was reported by the authors.