1.1 Introduction
Construction site material wastes are those materials supplied to the site for construction but were not used (Oyegba, 2013). Construction material waste has both environmental and cost performance consequences. Construction site consists of unwanted materials produced or incidentally by the construction. This includes building materials such as mortar, nails, electrical wires, as well as waste originating from sure preparations such as dredging materials, tree stumps, and rubble. Construction waste may contain asbestos and other hazardous substance which is dangerous to human health. In this period of global economic recession and environmental awareness, it has become necessary to adopt effective waste reduction strategies in order to reduce the cost of construction projects as well as produce environmental friendly projects.
As a prelude to other parts of this study, this chapter will discuss the background upon which this study was initiated, the statement of problems that led to this study, the Aim and Objectives of the study. Others are Significance of the study, Scope of work, Research hypothesis and questions, Limitations of the Study and Definition of technical terms.
1.2 Background of Study
In Nigeria, most construction site is not implementing any of the known contemporary approaches to waste minimisation consciously, resulting in wastes being generated uncontrollably. It is pertinent, therefore, to assess the extent of utilisation of these material waste control construction methods (MWCCM) for alleviating material waste problems, and domestically establish their potentials in reducing waste on-site.
Construction site waste management has become essential to improve the performance of the industry in terms of economic quality and sustainability. One way of achieving this target is by reducing waste at all stages of the construction process. Managing building material waste can result in higher construction productivity, save time and assist sustainability (How Q., 2000).
The construction industry contributes immensely to the development of any nation, however, in spite of the benefits it brings; it is equally known for producing immense amounts of wastes (Thurnau, 2013). The Modular Building Institute (MBI, 2011) has confirmed that the waste generating capacity of the industry in the US is staggering, amounting to about 135 million tonnes of debris to landfills every year. Many building waste is made up of materials such as bricks, concrete and wood damaged or unused materials for various reasons during construction. Observational research has shown that this can be as high as 10% to 15% of the materials that go into a building, a much higher percentage than the 2.5 to 5% usually assumes by the quantity surveyors. Since considerable variability exists between construction sites, there is much opportunity for reducing this waste.
Materials used for construction comprise a significant cost part in any development venture. The total expenses on materials might be between 50 to 70 percent or a more considerable amount of the actual expense of project development (Karoriya & Pandey, 2018; Albert, Shakantu & Ibrahim, 2018), although the manufactured cost might be a minor piece of the aggregated cost, most likely under 20 to 30 percent (Perdomo, 2004). The vast increases of development in material waste minimisation recognised by various researchers are said to incorporate money related, social, natural, improvement of contractor and subcontractor worker‟s image, higher productivity, development time reserve funds, and wellbeing on building locales (Jayamathan & Rameezdeen, 2014).
Although statistics are unavailable to quantify the amount of wastes generated on construction sites in Nigeria, a similar submission by Oladiran (2009) confirms that materials wastes pervade the Nigeria’s construction sites. In fact anecdotal evidence reveals practices such as poor storage system, poor material control and wrong material specification which generate waste and increase construction cost. Apart from overburdening the limited landfill sites as Gray (2013), MBI (2011) and Poon, Yu and Jaillon (2010) revealed, material wastes result to unnecessary high construction costs and great hindrances to affordability of good houses to the citizens (Oladiran, 2009).
Therefore, in Ede, Osun State where the research was carried out, the activities that was conducted is to know the Effect of Materials Resources Control on Construction Site Waste Reduction.
1.3 Statement of Problems
Investigation revealed that material waste has been recognized as a major problem in the construction industry. Not only waste has an impact on the efficiency of the construction industry but also on the overall economy of the country. It’s proved that the construction material waste has a negative effect on the environment. In Nigeria, very little consideration is given to control the generation of material wastes, and this is blamed on low environmental awareness of construction waste in the country (Wahab and Lawal, 2011). Cesare and Isatto (2002) stressed that high levels of waste could result to reducing the future availability of materials and energy and create unnecessary demands on the transportation system.
Furthermore, as about 30 to 70% of construction cost is consumed by materials (Khyomesh, 2011 cited in Ayegba, 2013), the need to reduce cost of construction through effective material management has become paramount more especially as Nigeria faces the period of economic recession.
1.4 Aim and Objectives of Study
The aim of the study is to investigate the Effect of Materials Resources Control on Construction Site Waste Reduction using Ongoing Construction Sites of Tertiary Institutions in Ede, Osun State as a case study. In achieving this aim, the following specific objectives were laid out as follows:
- To ascertain the possible measures towards the material waste reduction in construction industry;
- To determine the important sources of waste in construction;
- To examine the effectiveness of material management policies that exist on construction site;
- To identify the effective waste reduction methods in building construction sites; and
- To identify the key techniques that can help to minimize building material wastage on construction site.
1.5 Research Questions
The study came up with research questions so as to be able to ascertain the above stated objectives. The specific research questions for the study are stated below as follows:
- What are the possible measures towards the material waste reduction in construction industry?
- What are the important sources of waste in construction?
- How effective are material management policies on construction site?
- What are the effective waste reduction methods in building construction sites?
- What are the key techniques that can help to minimize building material wastage on construction site?
1.6 Research Hypothesis
In order to pursue the objective of this study, the following generalized statements have been designed to guide and aids in obtaining the result for the experiment to be conducted. For this work, the null hypothesis will be represented with H0 while the alternative hypothesis will be represented with hypothesis H1.
Hypothesis One
- H0: There is no significant correlation between waste generation on-site and material waste control construction methods
- H1: There is a significant correlation between waste generation on-site and material waste control construction methods
Hypothesis Two
- H0: There is no significant factor inhibiting construction site material waste reduction.
- H1: There is a significant factor inhibiting construction site material waste reduction.
1.7 Significance of Study
The relevant building authority will benefit immensely from this research as the findings of this study will help them to technically coordinate and organize their skills in inspecting and monitoring all construction activities with an aim to ensure compliance to building codes and standards.
Finally, the findings will benefit the Student and the Society at large, in the sense that, the Student will be able to make similar research work by making reference to this research work if published and well kept for consultation. And the society will also benefit from this research by getting pleasures from uncompromised built structures by a group of trained professionals.
1.8 Scope of Study
The scope of the research is focused on the Effect of Materials Resources Control on Construction Site Waste Reduction using Ongoing Construction Sites of Tertiary Institutions in Ede, Osun State as a case study.
1.9 Limitations of the Study
During the course of this study, many things militated against its completion, some of which are:
- Time Constraint: The time frame given to accomplish this project was very short due to school academic calendar and it was carried out under pressure which made the researcher not to implement some necessary features.
- Research material: availability of research material is a major setback to the scope of the study.
- Frequent power failure: This made the researcher append more money on fuel to ensure sustainable power.
- Financial Constraint: Insufficient fund tends to impede the efficiency of the researcher in sourcing for the relevant materials, literature or information and in the process of data collection (internet).
1.10 Definition of Terms
Construction Material Wastes (CMW): CMW are those materials supplied to the site for construction but were not used (Oyegba, 2013).
