2.1. Concept of Green construction practices
The terms “green construction”, “cleaner construction”, and “sustainable construction”, are frequently used interchangeably (Shurrab et al., 2019). GCPs can be defined as practices undertaken with the intention of ensuring construction quality and safety, resources are conserved, and reducing the harmful effect of construction activities on the environment through energy management, land management, water savings, and materials management (Iqbal et al., 2021; Jiang et al., 2019; Rahman et al., 2021). Additionally, Jiang et al. (2019) define GCPs as an all-encompassing view of sustainable development in the construction industry. Similarly, Shurrab et al. (2019) refer to GCPs as the use of onsite practices aimed at minimizing the negative environmental impact of construction activities.
The idea behind GCPs transcends the construction of buildings without posing any negative effect on the natural environment since it seeks to create conditions that ultimately lead to the improvement in the quality of the environment (Wu et al., 2019). Simply put, GCPs are a combination of attempts geared towards building in a responsible manner, while reducing waste, controlling material usage, managing energy use, managing stormwater, and preserving the environment. GCPs takes into consideration conservation needs and utilizes resources more efficiently than conventional construction practices (Ofek et al., 2018).
2.2 Green construction practices and Client satisfaction
CS is the accomplishment of the expectations the client had, before the start of the project, and the actual performance which can be measured at the various phases of the construction project (Li et al., 2013). CS has gained popularity in the measurement of project performance as an addition to the traditional performance criteria of cost, quality, and time (Davis, 2016).
CS is of utmost importance in the adoption of GCPs (Presley & Meade, 2010). However, many clients today do not fully appreciate the benefits of GCPs due to their seeming lack of understanding of its merits (Shan et al., 2020). This has led to a situation whereby clients become doubtful concerning the capacity of GCPs to satisfy their needs (Zhao et al., 2018). This is in tandem with the findings of Windapo (2014) who opined that clients are not likely to adopt GCPs for the purpose of environmental protection without government pressure and any financial benefits accruable to them. Even though the number of clients accepting to adopt GCPs has been on the increase, their choice to adopt these practices is passive, since they are been compelled by the government to do so (Shan et al., 2020). This could lead to a situation whereby they may not be satisfied as they ought to be when such practices are been adopted on their projects due to cost overrun, delays, increase in complexity, and risks (Onubi et al., 2019).
Adopting GCPs has been reported to be associated with an increase in the scope, increase in complexity, and the use of novel technologies in construction projects which may increase project costs and decrease the anticipated profit of the client (Ofek et al., 2018), thus negatively impacting on CS. Consequently, there has been a seeming lack of interest by clients in GCPs (Venkataraman & Cheng, 2018). Additionally, most clients intend saving money in every project regardless of whether GCPs are adopted or not, however, most of the green construction projects’ cost surpasses the original contract sum (El-Sayegh et al., 2019; Zhao et al., 2020), hence creating an inverse relationship between GCPs and CS. A similar study conducted in the tourism sector on the effect of green practices on CS reported that there exists no significant effect (Assaker, 2020).
The importance of schedule performance in any construction project and the role it plays in CS cannot be overstated. Gurgun and Koc (2020) report that compliance to schedule requirements was topmost among clients’ performance criteria in GCPs. However, it has been proven that projects adopting GCPs are often more susceptible to schedule overruns compared to conventional construction projects (Bakchan et al., 2019), thus impacting negatively on CS on green construction projects. In view of the leanings from the literature reviewed, it is hypothesized as follows:
GCPs has a negative significant effect on CS.
2.3 Mediating effect of health and Safety performance on the relationship between Green construction practices and client satisfaction
A construction project’s HSP is a measure of the level to which both the primary and secondary stakeholders of the project are been exposed to or affected by accidents, get injured, and/or are susceptible to other health-related issues resulting from construction activities (Ammad et al., 2020). The HSP of construction workers is considered a vital part of green construction (Hinze et al., 2013). However, early studies related to safety in green construction have reported that the adoption of GCPs poses greater safety risks to construction workers compared to conventional construction methods (Hwang et al., 2018). Also, Dewlaney and Hallowell (2012) found that the unfamiliar tasks, new materials, innovative technologies, and processes involved in GCPs are responsible for the safety risks reported in previous studies. Similarly, Karakhan and Gambatese (2017) observed that the severity of safety risk and exposure to hazards of construction workers is heightened when GCPs are adopted.
Contrary to the above, Cianciarullo (2019) opined that GCPs can lead to HSP with adequate planning and experienced construction workers. For example, Zhou et al. (2015) opined that HSP can be achieved in these projects if necessary measures are taken at the design stage of the projects. Similarly, Karakhan and Gambatese (2017) opined that the safety issues associated with GCPs can be prevented through strategies adopted during design. As such, many green building rating tools such as LEED have included credits for the prevention of safety issues through design (Karakhan & Gambatese, 2017). In view of the increased quest and measures taken towards HSP in projects that adopt GCPs, Khan et al. (2021) report that there has been significant improvement in the HSP during CCP adoption. Yusliza et al. (2020) report that CCP are largely expected to lead to HSP. Also, Sang et al. (2018) acknowledged that the technology involved in GCPs is complex but not highly unsafe.
The HSP benefits resulting from the adoption of GCPs are anticipated to yield both monetary and non-monetary benefits such as cost benefits, schedule performance, increased project quality, and greater workers’ productivity (Howarth & Watson, 2010). Due to the merits of completing the project within schedule, without cost overruns, without accidents, and complying with government environmental regulations, the clients are expected to be satisfied with the project delivery process (El-Sayegh et al., 2019). Also, since GCPs techniques and methods have usually been considered to be more expensive, more time consuming, more complex than the traditional construction methods thus leading to client dissatisfaction and reluctance to adopt these practices (Zhao et al., 2020), it is anticipated that the guaranteed HSP emanating from the adoption of GCPs as stated earlier would reduce the cost burden originating from safety issues, risks, less delay due to fewer accidents and less absenteeism thus leading to CS. In other words, GCPs can lead to CS through HSP. Consequently, we hypothesize as follows:
HSP mediates the relationship between GCPs and CS.
2.4 Moderating effect of green construction practices on the relationship between health and safety performance and client satisfaction
In the preceding section (Sect. 2.3), previous studies had shown that HSP has a positive effect on CS. However, we contend that the nature and the magnitude of the effect will differ considerably depending on the level to which GCPs are been practiced on the construction projects. In a study carried out in Nigeria, Oladokun et al. (2020) found out that construction professionals view GCPs adoption as the major determinant for CS in the country. Client demand has been tagged as the major driver that propels contractors to adopt GCPs (Athapaththu & Karunasena, 2018). Similarly, Shurrab et al. (2019) opined that clients are in the know of the merits of GCPs as a means of preserving the environment and are willing to pay the required cost. Ochieng et al. (2014) assert that CS is a measure of sustainability on construction projects as clients are increasingly demanding that contractors adopt GCPs. All these show that construction clients acknowledge the importance of adopting GCPs and demand for it. To the best of our knowledge, no study in the construction field has examined the moderating effect of GCPs on the relationship between HSP and CS. But in the tourism sector, Lee et al. (2018) reported a negative significant moderating effect of green practices on the relationship between service quality and CS. However, from the insights gotten from past studies, the positive effect of HSP on CS will be stronger with a higher GCPs adoption relative to projects with a low level of adoption of GCPs. Building on these arguments, it is hypothesized that:
The effect of HSP on CS will be stronger when GCPs adoption is high.
The conceptual model of the study containing the study’s hypotheses is shown in Fig. 1.