Effect of energy management and waste management on schedule performance: role of technological complexity and project size.

Schedule overrun is one of the greatest hindrances to construction project performance, thereby making schedule management an integral part of construction project management. The aim of this study is to examine how the effect of sustainable energy management (SEM) and sustainable waste management (SWM) on schedule performance (SP) is mediated by technological complexity (TC) and moderated by project size (PS). Data were obtained by means of a questionnaire survey of 168 completed construction projects in Nigeria. The partial least squares structural equation modelling (PLS-SEM) technique was adopted in analysing the collected data. The results show that TC partially mediates the relationship between SWM and SP, while TC fully mediates the relationship between SEM and SP. Also, the findings of the study indicate that the negative effect of SWM on SP will be greater with large PS. This study contributes to previous studies in the area of schedule management, by providing empirical proof to explain the means through which SWM and SEM could lead to SP through TC, and how this would vary depending on PS. The study proffers ways for contractors to improve the SP of their projects considering PS and TC.

Green construction practices: ensuring client satisfaction through health and safety performance.

Studies have proven that client satisfaction (CS) is greatly affected by the nature of construction practices on site. However, not much attention has been given to CS in projects that adopt green construction practices (GCPs). This study examines the effect of GCPs on CS, and the means by which CS can be achieved through health and safety performance (HSP). This study also analyses how the relationship between HSP and CS could vary depending on the level of GCPs adopted. A questionnaire with 27 items drawn from literature was used in collecting data from class A contractors in Nigeria. The study's hypotheses were tested using the partial least squares structural equation modelling (PLS-SEM) technique. The findings of the study reveal that GCPs have a positive effect on CS. HSP proved to only partially mediate the relationship between GCPs and CS. The findings also show that the effect of HSP on CS is moderated by GCPs with the stronger effect from projects with low adoption of GCPs. The study's findings highlight the pivotal role of HSP in ensuring CS in construction projects that adopt GCPs. This study makes practical contributions to the body of existing knowledge by highlighting the need for concerted efforts by contractors such as investing in health and safety training and ensuring site workers wear personal protective equipment aimed at adhering to acceptable health and safety standards. This can be achieved through provision of funds for safety activities, monitoring, and supervision of workers to guarantee HSP which translates to CS while adopting GCPs. However, the obstacles to these are the lack of safety culture by construction organizations, lack of enlightenment on the part of construction site workers, and poor safety climate on the construction project site. Additionally, the study provides greater insight on the practice of green construction among contractors by showing that the effect of HSP on CS would differ considerably on account of the level of GCPs adopted.

Analyzing the mediating effect of economic performance on the relationship between green construction practices and health and safety performance in Nigeria.

The adoption of green construction practices (GCP) has been on the increase in recent years as a means of reducing the negative effects of construction on the natural environment. However, GCP have been discovered to expose the construction workers to numerous health and safety (HS) risks, resulting from a decline in safety investment due to the economic burden associated with its adoption. This study explores the means through which GCP influence the HS performance of construction projects through economic performance. To obtain the views of contractors, a survey questionnaire was developed, and data was collected from project managers and site managers of "class A" contractors, with a response rate of 81.55%. The partial least squares structural equation modeling (PLS-SEM) technique was adopted to analyze the data. The results show that the effect of GCP on HS performance is fully mediated by economic performance. The study concludes that for projects that adopt GCP to have high levels of HS performance, they are required to have an optimal economic performance. Efforts should be intensified by the government in providing subsidies, tax waivers, and other incentives for adopters of GCP to ensure the economic performance of their projects since it guarantees high HS performance.