Thesis Abstract

<p>          <b>ABSTARCT</b><br></p><p> Material waste generated by the activities of the construction industry poses serious danger to both the construction projects concerned and the environment at large. Previous researches both at local and international level have neglected construction operatives and craft men who are the majority stakeholder. The study was aim to assess the perception of construction operatives, Tradesmen and Artisans on materials waste generation in the construction industry, with a view to encouraging better performance of construction projects in Nigeria. The study employed questionnaire survey. Tables and figures where used to present the collected data and Mean item score (MIS) and percentage were used to analyze the data collected. Kruskal-Wallis test and Mann-Whitney U-Test were used to test the hypotheses. It was discovered that formwork from wood/timber, Mortar from Rendering/plastering and Blockwork/ Brickwork are the most wasteful material generated on sites; Design (Frequent design changes and poor design), Poor materials storage system and Theft and vandalism are the most important factors that influence material waste generation during construction; Proper site supervision and management techniques, Adequate storage of material, and Staff training and awareness on waste management are the measures of minimizing construction material waste; and saving cost of disposal and transport, increased profit and save construction time loss are the most important benefits of material waste minimization. It was recommended that site operatives and craft men should be carried along in every management decision regarding waste management plan development as they constitute the major stakeholders on sites.&nbsp;</p><p><b><i>Keywords Construction Industry, Construction Operatives, Material waste, Nigeria, Tradesmen and Artisans </i></b> <br></p>

Thesis Overview

<p><b>1.0 INTRODUCTION</b></p><p><b>1.1 BACKGROUND STUDY</b></p><p>The construction industry is the backbone of every nation, as it is one of the forces driving the socio-economic growth and development of nations of the world [1]. It improves the quality of live through the provision of infrastructure like roads, schools, hospitals, and other necessary basic facilities [2]. Construction industry is the leading sector in any country [3]. In spite of the benefits derived from this industry, the activities of the industry generates increasing quantities of waste which has created a bad image for the industry; and also deplete the limited natural resources [3]. [4] described the construction industry as one of the largest and most important industries; and at the same time the major consumer of natural resources and one of the largest polluters. The wastes generated by the industry have not been well managed, thereby causing considerable health and environmental problems [5]. Also these wastes have affected the performance of many projects in Nigeria ([6], [7], [8]). [9] opined that ineffective material planning and control on construction sites could result to poor performance and unplanned outcomes of construction projects. Construction projects are faced with severe problems of time and cost overruns, as well as construction waste ([10], [11], [12]).<br></p><p> According to [13] any material apart from earth material which needs to be transported elsewhere to the construction sites or used within the construction site itself for the purpose of land filling, incineration, recycling, reusing, or composting rather than the intended specific purpose of the project due to material change excess nonuse, or noncompliance with the specifications or being a byproduct of the construction process is regarded as construction waste. [14] defined building material wastage as the difference between the value of materials delivered and accepted on site and those properly used as specified and accurately measured in the work after deducting the cost saving of substituted materials transferred elsewhere in which unnecessary cost and time may be increased by the material wastage. [15] see construction waste as the difference between what was purchased and what was actually used. Waste is any surplus or unwanted material persistently causing environmental issues and global warming [16]. Construction waste can have a significant impact on cost, time, quality and sustainability, and also on the success of projects [16]. Construction materials significantly contribute to the total cost of construction, and the wastage of these materials will negatively impact on the contractors profit, construction cost and duration, and can cause dispute among key project participants [17]. <br></p><p> [18] carried out an Investigation into Waste Management on Construction Sites in South Western Nigeria. The study focused on the dangers posed by material waste in the construction industry, ways of minimizing construction waste, ways of keeping proper site records for accountability sake. And recommend effective waste management measures. This research adopted questionnaires to collect data from construction professionals, and employed tables and statistical indices for the data analysis. The study revealed that material wastage increase the cost of construction project and reduce contractor‟s profit. And attributed construction was to poor management and lack of effective waste management awareness. The study recommended that construction waste management should be recycled and reused. And through giving incentives to workers for proper handling, material wastage is reduced; and trained personnel should be used as supervisors. [19] evaluated waste control measures in construction industry in Lagos, Nigeria. The study assessed the forms, causes and factors incidental to waste and measures to effectively control construction waste. The study adopted questionnaire, interview and site visit to collect it data from construction professionals. Study used Relative Important index, frequency and percentages to analyze its data. The study reported that factors incidental to waste, design variation are caused by last minute client requirement; cost of construction materials was major factor influencing construction materials selection; and construction cost factor leads to method of construction. The study revealed that most firms do not calculate waste indices which could assist them to determine the amount of waste generated, and no proper sorting exercise of waste during construction. Also, most firms do not incorporate “waste management plan” in their tender documents. To control waste, designers should coordinate dimensions between materials specified and those procured, proper material handling, storage and usage were advocated and that “waste management plan” should be incorporated in tender submission of contracting firms. [20] carried out a study on Quantitative Assessment of Construction Materials Wastage in the Nigerian Construction Sites. The study‟s purpose was to quantitatively assess construction materials wastage in construction sites with a view to providing background information at the design stage on allowable percentage of construction materials waste that will enhance construction project delivery. The study used structured questionnaires to collect data from construction professionals in Abuja municipal, Nigeria. The study analyzed its data using average, percentage and relative significant index (RSI). The study found out that the most type of waste on construction site is theft and vandalism, cutting waste, transit waste and application waste. The study concluded that 15.32% are construction materials waste in the Nigerian construction sites; and recommended 15- 20% allowance for all types of construction materials waste in Nigeria. <br></p><p> [8] evaluated the causes of construction waste generation on building sites in rivers state, South-South of Nigeria. The study studied the factors affecting construction material waste generator; and determine if there is a statically significant difference in perceptions about the factors between the contractors and consultants. They adopted literature review and structured questionnaire in the collection of data. And analyzed the collected data using mean score method, ranking method and Mann-Whitney U test. The study focused on consultants and contractors as their key respondents. The study revealed that rework contrary to drawing and specification, design changes and revision and waste from uneconomical shapes, were the most important factors contribution to construction material waste. The study also showed that there is no significant difference between the consultants and contractors regarding the factors affecting construction material waste. [21] carried out a study on Materials Waste In The Egyptian Construction Industry. The study which whose aim was to identify and quantify waste generation rates and their causes in the Egyptian Construction Industry used a survey questionnaire as a diagnostic tool for collection of data. The questionnaires were distributed among construction professionals. The study discovered that „late information‟ and „Changes to design‟ were among the most fundamental causes of material waste. [22] studied Non Value-Adding Activities In Australian Construction Projects. The study was aimed at determining the incidence of non value-adding activities that occurred within contracting organizations in Australia. They adopted a quantitative approach and used questionnaire for its data collection. The questionnaires were administered to construction professionals. The study revealed that there was no significant difference between respondents‟ perceptions towards waste. Also, the key waste cause variables of non valueadding activities are; waiting for instruction, poor quality site documentation, weather, unclear drawings, poor design, design changes, slow drawing revision and distribution and unclear specifications.&nbsp;</p><p>&nbsp; carried out a study which was aimed to Evaluate Materials Wastage and Control in Some Selected Building Sites in Nigeria. They used questionnaires which were administered via accidental sampling technique to construction professionals in the selected building sites. The data collected was analyzed using descriptive statistics tools. Also, [10] carried out a study on Construction Material Waste Management Practices by Construction Firms in Nigeria. They used of structured questionnaires for data collection, and administered them to senior construction-professional personnel of construction firms. The study showed that Block work has the highest level of waste generation and adequate site supervision and control is the most important strategy for minimizing materials wastage on sites. And also the estimators‟ allowances for materials wastage are exceeded for most materials on sites.<br></p><p> Studied the Causes and Magnitude of Wastage of Materials on Construction Sites in Jordan. The research aims to study the causes and magnitude of wastage of construction materials on construction projects sites in Jordan. The researcher used a questionnaire form which was designed to help achieve the research aim. The questionnaire form was distributed to 240 participants (clients, contractors, and consultants) who are mainly construction professionals. The study discovered that the most important causes of wastage of materials on construction sites in Jordan are frequent design and client‟s changes; rework due to workers mistakes; poor contract documents; wrong and lack of storage of materials; poor strategy for waste minimization; shortage and lack of experience of skilled workers; poor site conditions; damage during transportation; theft and vandalism; and mistakes in quantity surveying and over allowance. They concluded that the percentage of wastage materials is accounted for by values between 15% and 21% on Jordanian construction sites. [3] studied Factors Affecting Material Waste on Construction Sites in Nigeria. Their study assessed the level of contribution of several factors to construction material waste generation; and used structured questionnaires which were administered to two groups of stakeholders (consultants and contractors) in construction industry. These two groups of stakeholders are construction professionals. They used Relative contribution index, MannWhitney U and Kruskal-Wallis tests was used to analyze the collected data. They found that the highest contributors to materials waste are reworks due to non-conformance to specifications, waste from cutting uneconomical shapes, and design changes and revisions. Also, location of site has no effect in the level of contribution of the assessed factors to material waste generation. And they concluded that material waste generation is a critical and complex issue in Nigerian construction industry. [25] researched on Material Control Strategies In Some Selected Construction Firms In Nigeria. The purpose of the study was to assess the various strategies utilized by building construction firms for controlling materials on construction sites. Also, to identify the stages of in the course of the project execution in which adequate material control adopted; to assess the impact of building construction firms‟ adherence to standard material control strategies on building project performance and delivery. They used well-structured questionnaire administered to construction professionals to collect data. They found out that recognition of material control practice and implementation of the strategies involved by building construction firms would ensure timely project execution and standard work delivery within reasonable cost, time and quality. [7] carried out a study on Professionals‟ views of material wastage on construction sites and cost overruns in Lagos state, Nigerian South-West. The purpose of the study were to identify the most wasteful building material during construction operation; to assess the level of material wastage with various subcontracting options; to identify factors contributing to material waste on building sites; to determine the percentage contribution of material wastage to project cost overrun, and to examine the relationship between the level of waste generated from building material, subcontracting options and project cost overrun. The study employed a survey research design and focused on construction managers, site managers, chief estimators, site engineers, projects managers and other key personnel within the construction industry. Data collected for the study were analyzed using Frequency, percentages, mean score, Pearson correlation coefficient, and Chi-square. The study revealed that mortar from plastering/rendering is most wasteful building material during construction operations on site; the subcontracting option that is the highest contributor to building material wastage is „labour only‟ subcontracting options; an Average of between 21-30% of project cost overrun in construction is attributable to building material wastage; Factors that dominate among the contributors to material wastage on site are poor supervision, re-work, and poor material handling; and there is a significant relationship between waste generated from building material during construction, subcontracting options and cost overrun. <br></p><p>Carried out a study on Material Waste Management In Construction Industries of India. The stud investigated the cause of waste, waste prevention method and the wastage level in construction site. The study adopted a questionnaire survey. Questionnaires were administered to construction professionals. The study adopted weighted average and coefficient of variation criteria and T-test statistical technique of comparing means. The study reported that Design Changes during construction, weak material management, poor site storage facilities, errors by tradesmen and severe weather conditions were the major factors affecting waste generation. Adequate storage of material is one of the major minimization measures. The study recommended a holistic and analytical approach to construction waste management problems. [27] examine the effects of material-waste and their control measures on project-cost overruns at the sitemanagement stage of a project. The study employed interview and purposive sampling techniques in the collection of data from respondents who mostly construction professionals. The data collected were analyzed using descriptive statistics (frequency and percentages) and inferential statistical method. The study revealed that Rework, site accidents, inadequate site security/fencing, poor site organization and discipline, and constructionsite disputes; are the causes of material waste that have the greatest effect cost overruns at the site-management stage of a project. The study also reported that; Tight security onsite (security source), inadequate site organization and discipline (operation source), and onsite and offsite reuse of waste materials (site conditions and management source); are material waste-control measures that have the greatest effect on cost overruns with respect to the quality of site management of a project. The study also revealed that there were no significant differences in the views of the professionals on these issues. It is evident that previous studies have focused only on the perception of construction professionals, leaving out the site supervisors, operatives and craft men who are the ones that are both physically and directly involved in the carrying out the construction works and the production of the finished building. An effort to carry the site supervisors, operatives and craft men, who are the majority stakeholder in construction, will help improve the performance of construction activities and reduce waste production and other related losses during the construction stage of the projects. [8] describe the site supervisors and the site operatives as people who are directly involved in the art of putting the raw materials together to form the building envelope. [28] refers to this group as „project staff‟, and defines them as the member of the project team who carry out the work of creating the deliverables. However, it is clear from previous researches both at local and international level that these groups of stakeholders have been neglected. It is against this backdrop that this study is predicated. The outcomes of this study will enable the clients, consultants, contractors, and construction professionals know that site operatives and craft men are aware of material waste and are conscious of contributing to their reduction during construction. The outcome will also add to the body of knowledge available on construction waste management. Overall, construction operatives and craft men will be considered important stakeholders in the scheme of things regarding making decision in construction operations that relate to construction waste generation and management. <br></p><p> <b>1.2 AIM AND OBJECTIVE</b></p><p>The aim of this study is to assess the perception of construction operatives, Tradesmen and Artisans on materials waste in construction, with a view to encouraging better performance of construction projects in Nigeria. To achieve this aim, the following are the objectives of the study;&nbsp;</p><p>i. To identify the most wasteful material produced during construction operations&nbsp;</p><p>ii. To determine the most important factors that influence material waste production during construction work</p><p>&nbsp;iii. To assess measures of minimizing construction material waste</p><p>&nbsp;iv. To identify the most important benefit of material waste minimization.&nbsp;</p><p><b>1.3 RESEARCH HYPOTHESES</b>&nbsp;</p><p>The followings are the hypothesis that guide the study and they stems from objectives (i), (ii) and (iii) H1: there is no significant statistical difference in the perceptions of the various groups of operative and craft men concerning the most wasteful material produced during construction operations H2: there is no significant statistical difference in the perceptions of the various groups of operative and craft men concerning the factors affecting material waste in construction H3: there is no significant statistical difference in the perceptions of the various groups of operative and craft men concerning the measures of minimizing construction material waste <br></p>