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RISK LEVEL OF FACTORS CAUSING CONSTRUCTION WASTE
GENERATION THROUGHOUT CONSTRUCTION PROJECT LIFE CYCLE
NOR SOLEHAH BINTI MD AKHIR
A thesis submitted in
fulfillment of the requirement for the award of the
Degree of Master of Civil Engineering
Faculty of Civil and Environmental Engineering
Universiti Tun Hussein Onn Malaysia
APRIL 2015
v
ABSTRACT
The construction industry has an adverse impact on the environment from the wastes
generated during construction work. The amount of wastes generated increases
yearly due to rapid economic growth worldwide which includes Malaysia. Due to
waste generation, one of the major issues faced is the increase of illegal dumpsites.
The illegal dumping may caused a risk to human health and environment. Thus, it
calls for serious measures to regulate wastes generation. The waste is generated due
to various factors throughout construction project life cycle (CPLC). For controlling
purpose, it is very important to identify the generation factors and also to determine
the level of risk from each factor. Hence, this study focuses on assessing the risk
level of factors causing wastes generation throughout CPLC. Besides, it also
proposes mitigation measures for the high risk factors. For assessing the risk level, a
total of 33 factors that causes construction wastes generation that have been
identified from literature review were considered. The assessment involved 15
experts who are experienced in handling construction projects. This investigation
adopted two rounds of Delphi method in determining level of occurrence and
severity of each factor in relation with different phases of CPLC. The experts were
required to fill out the questionnaire set and the analysis on the gathered data from
the questionnaire work was done using risk matrix. The result indicated that in the
construction phase, majority of the identified factors occurred in this phase are
critical due to having high risk level and most of them are categorised in Human
Resource/Manpower (HRM) group. It is followed by finishing phase, design phase,
and planning phase. However, in planning phase, the chances of wastes generation
are minimal with no high risk factors. In order to control the construction wastes
generation problem, mitigation measures for high risk factors were proposed. The
findings of this study can be a useful guide for the practitioners in controlling
construction wastes generation.
vi
ABSTRAK
Industri pembinaan telah menyumbang kesan buruk terhadap persekitaran akibat
daripada penjanaan sisa semasa kerja pembinaan. Jumlah penjanaan sisa kian
meningkat setiap tahun disebabkan pertumbuhan ekonomi yang semakin pesat di
seluruh dunia termasuk di Malaysia. Hal ini menyebabkan jumlah tapak pelupusan
sampah secara haram semakin meningkat. Tapak pelupusan sampah yang berleluasa
boleh mendatangkan risiko kepada kesihatan manusia dan alam sekitar. Oleh yang
demikian, perhatian yang serius diperlukan bagi mengawal masalah ini. Penjanaan
sisa boleh berlaku disebabkan pelbagai faktor di sepanjang kitaran hayat projek
pembinaan (CPLC). Bagi tujuan pengawalan, ia adalah penting untuk mengenalpasti
faktor-faktor penyebab penjanaan sisa dan juga menentukan tahap risiko bagi setiap
faktor. Oleh itu, kajian ini fokus kepada menilai tahap risiko bagi faktor-faktor
penyebab penjanaan sisa di sepanjang CPLC. Di samping itu, kajian ini juga
mencadangkan langkah-langkah mengatasi untuk faktor-faktor yang berisiko tinggi.
Untuk menilai tahap risiko, sebanyak 33 faktor penyebab penjanaan sisa pembinaan
yang telah dikenalpasti daripada kajian literatur dipertimbangkan. Penilaian ini
melibatkan 15 orang pakar yang berpengalaman dalam mengendalikan projek-projek
pembinaan. Dua pusingan kaedah Delphi digunakan bagi menentukan tahap berlaku
dan tahap impak setiap faktor bagi setiap fasa di sepanjang CPLC. Pakar-pakar
diminta untuk mengisi borang soal selidik dan analisis yang dilakukan ke atas data
yang diperolehi adalah dengan menggunakan matrik risiko. Keputusan mendapati
bahawa dalam fasa pembinaan, sebahagian besar faktor-faktor yang dikenal pasti
berlaku dalam fasa ini adalah kritikal kerana mempunyai tahap risiko yang tinggi dan
kebanyakan faktor yang berisiko tinggi adalah dari kategori Sumber Manusia/Tenaga
Kerja (HRM). Ia diikuti dengan fasa kemasan, fasa reka bentuk, dan fasa
perancangan. Walau bagaimanapun, dalam fasa perancangan kemungkinan
penjanaan sisa adalah minimum dan tiada faktor yang berisiko tinggi dalam fasa ini.
vii
Dalam usaha untuk mengawal masalah penjanaan sisa pembinaan, langkah-langkah
mengatasi bagi faktor yang berisiko tinggi telah dicadangkan. Hasil kajian ini dapat
menjadi panduan kepada pihak industri dalam mengawal penjanaan sisa binaan.
viii
CONTENTS
TITLE i
DECLARATION ii
DEDICATION iii
ACKNOWLEDGEMENT iv
ABSTRACT v
CONTENTS vii
LIST OF TABLES xi
LIST OF FIGURES xiii
LIST OF SYMBOLS AND ABBREVIATIONS xiv
LIST OF APPENDICES xv
CHAPTER 1: INTRODUCTION
1.1 Research Background 1
1.2 Problem Statement 2
1.3 Aim and Objectives 4
1.4 Scope of Study 4
1.5 Research Methodology 4
1.6 Thesis Organization 5
CHAPTER 2: LITERATURE REVIEW
2.1 Introduction 6
2.2 Risk Management in Construction Project 6
2.3 Construction Wastes 9
2.3.1 Definition 9
2.3.2 Construction Wastes Generated 11
2.3.3 Waste Management 13
2.3.4 Impacts of the Waste 17
ix
2.4 Causative Factors of Construction Waste
Generation
19
2.5 Causative Factors in Construction Project
Life Cycle
25
2.5.1 Construction Project Life Cycle
(CPLC)
25
2.5.2 Incorporation of Causative Factors
in CPLC
28
2.6 Mitigation Measures of Construction
Wastes Generation
32
2.7 Summary 34
CHAPTER 3: METHODOLOGY
3.1 Introduction 35
3.2 Flow of the Research 35
3.3 Questionnaire Development 36
3.4 Data Collection 38
3.4.1 Pilot Study 38
3.4.2 The Delphi Method 38
3.5 Analysis Method 41
3.5.1 Reliability Test 41
3.5.2 Descriptive Analysis 41
3.5.3 Risk Matrix 42
CHAPTER 4: ANALYSIS AND DISCUSSION
4.1 Introduction 44
4.2 The Pilot Study Analysis 44
4.2.1 Experts‟ Demography 45
4.2.2 Reliability Test 45
4.2.3 Analysis of Factors 46
x
4.3 Analysis of Delphi Survey 52
4.3.1 Respondents‟ Demography 52
4.3.2 Identification of Risk Level 55
4.3.3 Agreeability on Identified Risk
Level
60
4.4 Proposed Mitigations for Risk Factor 65
4.5 Summary 68
CHAPTER 5: CONCLUSION AND RECOMMENDATION
5.1 Introduction 70
5.2 Significant Findings 70
5.3 Limitations of the Study 74
5.4 Recommendations for Future Work 75
REFERENCES 76
APPENDIX 91
xi
LIST OF TABLES
2.1 Wastes definition 11
2.2 Construction wastes generated 13
2.3 Mapping of impact of construction waste 19
2.4 Mapping of factors contributing construction
wastes generation
23
2.5 Comparison between proposed CPLC with others
CPLC based on literature review
26
2.6 Factors of construction wastes according to CPLC 29
3.1 Scale represents the probability of occurrence and
level of severity
37
3.2 Applied Delphi method by researchers in
construction research
39
3.3 Suggested Delphi method for this study 41
4.1 Expert‟s demography in pilot study 45
4.2 Reliability test results 46
4.3 AI value of factors in each phase 47
4.4 Significant factors in each phase 48
4.5 Risk level of causative factor in the planning
phase
56
4.6 Risk level of causative factors in the design phase 56
4.7 Risk level of causative factors in the construction
phase
58
4.8 Risk level of causative factors in the finishing
phase
59
xii
4.9 Percentage of agreeability for the risk level of
causative factors in the planning phase and the
design phase
61
4.10 Percentage of agreeability for the risk level of
causative factors in the construction phase
62
4.11 Percentage of agreeability from panels for the risk
level of causative factors in the finishing phase
64
4.12 Proposed mitigation measures of high risk factors 65
xiii
LIST OF FIGURES
2.1 Six stage of waste management hierarchy 14
2.2 Construction project life cycle diagram 27
3.1 Research methodology flowchart 36
3.2 Process of the Delphi method 40
3.3 Risk matrix 43
4.1 Highest educational qualification of
respondents
51
4.2 Respondents‟ working experiences 53
4.3 Respondents‟ position 53
4.4 Type of organization of respondents 54
4.5 Category of organization of respondents 54
4.6 Highest contract amount of projects that
respondents have dealt with
55
4.7 Risk level of causative factor in the planning
phase
56
4.8 Risk level of causative factors in the design
phase
57
4.9 Risk level of causative factors in the
construction phase
59
4.10 Risk level of causative factors in the finishing
phase
60
5.1 Factors causing construction waste generation 71
5.2 Risk level of the factors throughout CPLC 73
xiv
LIST OF SYMBOLS AND ABBREVIATIONS
AI - Average Index
CPLC - Construction Project Life Cycle
CWDCS - Construction Wastes Disposal Charging Scheme
C&D - Construction and Demolition
DEL - Delivery/Procurement
EQP - Equipments
EXT - External/Unpredictable
GHG - Green House Gas
HRM - Human Resource/Manpower
IBS - Industrialized Building System
ICT - Information, Communication, and Technology
MAT - Material
PCM - Project and Contract Management
RIBA - Royal Institute of British Architects
SPSS - Statistical Package for the Social Sciences
WGR - Wastes Generation Rate
WMP - Wastes Management Plan
- Cronbach‟s Alpha Coefficient
xv
LIST OF APPENDICES
A Questionnaire Form: Pilot Study 91
B Questionnaire Form: Delphi Round 1 94
C Questionnaire Form: Delphi Round 2 97
D Description of the Factors 99
CHAPTER 1
INTRODUCTION
1.1 Research Background
Construction is an imperative industry that plays a vital role in the socio-economic
growth of a country. It provides necessary infrastructure and physical structure for
activities such as commerce, services, and utilities (Khan, Liew, & Ghazali, 2014).
Besides that, it also generates employment opportunities and enhances the nation‟s
economy by creating foreign and local investment opportunities (Wibiwo, 2003).
However, the industry is facing the problem of construction wastes generation. As
reported by Kartam et al. (2004), based on statistics and assumptions, a total of
Construction and Demolition (C&D) wastes production was estimated to be 1.6
million ton/year. According to Ferguson et al. (1995), over 50% of the wastes in a
typical United Kingdom landfill is contributed by construction wastes. Bossink &
Brouwers (1996) indicated that9% of the totally purchased materials ended up as
wastes. Furthermore, Masudi et al. (2011) stated that wastage level for major
materials in some projects in Malaysia may reach up to 10%.
This generation of wastes has negative impact to the environment, cost,
productivity, time, social, and economy of the industry (Kozlovská & Spišáková,
2013; Marzouk & Azab, 2014; Osmani, 2012; Wang, Kang, & Tam, 2008). In
addition, production of wastes may weaken the efficiency, effectiveness, value, and
profitability of construction activities (Augustine, 2011). Thus, the risk of generation
of construction wastes needs to be proactively managed.
2
There are various factors that contribute to generation of construction wastes.
These factors pose different levels of risk in wastes generation. Various researchers
have identified factors that contribute to wastes generation. As an example: A study
conducted in Sri Lanka revealed that the domestic construction industry workforce is
ignorant of the flow of activities that generated wastes (Senaratne & Wijesiri, 2008).
In Malaysia, it was found that there were five significant factors that caused
generation of construction wastes in this country. The factors are poor site
management or supervision, lack of experience, inadequate planning and scheduling,
mistakes and errors in design, and mistakes during construction (Nagapan, Rahman,
& Asmi, 2012a). In addition, contractors and consultants agreed that three most
important factors that contribute to generation of material wastes at construction site
are rework contrary to drawings and specification, design changes and revision, and
wastes from uneconomical shapes (Adeweyu & Otali, 2013).
A number of study highlighted that construction wastes are effectively
generated during the whole Construction Project Life Cycle (CPLC) from start until
completion of construction work (Kozlovská & Spišáková, 2013; Osmani, Glass, &
Price, 2008). It may be generated during planning, design, procurement, and
construction phase (Bossink & Brouwers, 1996; Ekanayake & Ofori, 2004; Wahab &
Lawal, 2011). While, several studies highlighted that construction wastes is
commonly generated during design and construction phase (Osmani, Glass, & Price,
2006; Panos & Danai, 2012).
Therefore, it can be concluded that construction wastes may be generated by
various factors and it may occur in the whole of CPLC. It also contributes to a lot of
negative impacts either to the project, environment or life. Thus, reducing wastes at
the source is the most effective measure in wastes management (Masudi et al., 2011).
By identifying the risk level of the factors and proposing the mitigations of the risky
factors, it may help the practitioners to figure out the best way to control this
problem.
1.2 Problem Statement
Production of construction wastes is directly related with the increasing demand of
infrastructure projects, residential development projects, and other facilities which
are required to improve the level of Malaysians‟ living conditions (Begum, Satari, &
3
Pereira, 2010; Nasaruddin & Ravana, 2008). Out of these projects, the construction
of residential building contributes the largest amount of construction wastes (Begum
& Pereira, 2011; Foo et al., 2013).
According to Oh (2014) in The Star daily publication in March 2014, Solid
Wastes Management and Public Cleansing Corporation highlighted that in 2007,
Kuala Lumpur generated 1.04 million metric tonnes of construction wastes per year
and this amount is expected to increase to 1.34 million metric tonnes a year by 2020.
However, these wastes were not properly handled by the construction parties
involved. Research studies have indicated that dumping of construction wastes in
landfill is a common practice in Malaysia (Foo et al., 2013; Nagapan et al., 2012a).In
2007, a study conducted by Rahmat & Ibrahim (2007) showed that 42% of the
wastes were dumped illegally in the district of Johor Bahru Tengah, Johor. The study
also found 46 illegal dumping sites in the district and most of them were located near
the road side. A study in the Klang Valley found only 20% of C&D wastes were
disposed at legal landfills while others were disposed at illegal landfills or private
lands (Begum & Pereira, 2011). There are also a number of contractors that disposed
material wastes through open burning especially timber and packaging wastes, and
also by burying concrete wastes (Masudi et al., 2011).
The wastes then pose a threat to the environment and society if they are not
handled properly. Thus, it is important to control the source of construction wastes
generation. Before it can be controlled, it is vital to identify the factors that
contribute to wastes generation. Previous studies had identified factors that caused
construction wastes generation (Ikau, Tawie, & Joseph, 2013; Masudi et al., 2011;
Nagapan, Rahman, & Asmi, 2012b). However, not much emphasis was given in
assessing the relative risk level of these factors towards construction wastes
generation, which is very important for proper planning and development of
strategies in controlling the factors. This has motivated the author to conduct this
research in identifying the risk level of various causative factors that occurs in CPLC
phases and propose mitigations of risky factors, which can serve as a useful guide for
the practitioners in controlling the construction wastes generation.
4
1.3 Aim and Objectives
The aim of this research is to assess the risk level of factors causing construction
wastes generation throughout CPLC. In order to achieve this aim, three objectives
have been established namely:
1) Identifying major factors causing construction wastes along the CPLC.
2) Determining the risk level of factor causing construction wastes along the
CPLC.
3) Proposing mitigation of the risky factors.
1.4 Scope of Study
The scope of this research is limited to construction-related companies in Peninsular
Malaysia. Data collection involves questionnaire survey using the Delphi method.
The survey is start conducted in the early of 2014. The targeted respondents are the
clients, consultants, and contractors whom are registered with CIDB between Grade
5 and 7. Respondents are selected among those who have more than ten years of
working experience in the construction industry. Construction wastes are limited to
material wastes only.
1.5 Research Methodology
This study is carried out based on the qualitative and quantitative mode of research.
It involves a comprehensive literature review from past researches to identify the
factors causing construction wastes generation. Based on that, a questionnaire is
developed to determine the factors occurrence and severity with respect to the
various phases of a construction project. The investigation for the developed
questionnaire is carried out using the Delphi method to assess the level of occurrence
and severity of the factors causing wastes generation for the construction industry in
Malaysia. The data are then analyzed using the average index and risk matrix to
identify the risk level of each factor. Mitigations of the risky factors are proposed
based on literature review.
5
1.6 Thesis Organization
This thesis is divided into five chapters as follows:
Chapter 1: This chapter describes the need of this study. It contains study
background, problem statements, objectives, scope of study, research methodology,
and thesis organization.
Chapter 2: This chapter elaborates on related literature through the published
research work. It includes the definition, wastes generation scenarios, handling the
wastes, and factors causing construction wastes generation. Besides that, the phases
in CPLC are discussed.
Chapter 3: This chapter describes how this research is carried out. It explains
the technique of data collection and the way to analyze them.
Chapter 4: The survey results will be illustrated in this chapter. It includes the
factors of wastes generation throughout CPLC, level of occurrence, severity, and risk
of the factors causing generation construction wastes throughout the CPLC. At the
end of this chapter, the mitigation measures of high risk factors are presented.
Chapter 5: This chapter presents the conclusion of the study. It also presents
some recommendations for future study and limitations that arise while this study
was conducted.
CHAPTER 2
LITERATURE REVIEW
2.1 Introduction
This chapter provides literature reviews that are related to this study. It is to
gain an overview of the current study and to provide a theoretical basis in refining
the research methodology and also the analysis approach for the current work. In this
chapter, risk management in construction projects, the definitions of construction
wastes, issues related to wastes generation, wastes management, impacts, and factors
causing construction wastes generations are reviewed. In addition, the concept of
four phases of CPLC is also discussed.
2.2 Risk Management in Construction Project
Project success can be defined by fulfilling the project objectives on the cost, time
and quality. However, to achieve project success, it is subjected to various risks due
to the unique features of construction activities, such as long period, complicated
processes, abominable environment, financial intensity, and dynamic organizational
structures (Zou, Zhang, & Wang, 2007; Akintoye & MacLeod, 1997). In addition,
Husin, Ismail, & Memon (2013) stated that the construction industry is always faced
with chronic problems such as time overrun, cost overrun, wastes generation,
imposing negative impacts to the environment, and excessive resource consumption.
Thus, risks in construction project have to be given serious attention so that the
project is successfully accomplished.
7
Risk can be defined as a combination of the probability and the severity, and
also the exposure of all hazards in the construction activity (Jannadi & Almishari,
2003). In managing risk, a systematic way is required to look into the areas of risk
and consciously determining how to treat the risk. It is a management tool that aims
at identifying sources of risk and uncertainty, determining their impact, and
developing appropriate management responses (Uher, 2003). A process of risk
management has been divided into three consecutive stages as stated by Perera et al.
(2014) and KarimiAzari et al. (2011) which are;
i. risk identification,
ii. risk analysis and
iii. risk response, where risk response has been further divided into four actions,
i.e. retention, reduction, transfer, and avoidance
For risk identification and risk analysis, it specifies and predicts the likelihood and
adverse impacts of risks; whereas for risk response, it is concerns on the measures
taken by project management to reduce the probability and effects of risks (Perera et
al., 2014).
Risk identification is a significant step in the risk management process, as it
attempts to identify the various risks affecting a construction project. In this stage,
risk factors that influence the project are detected, classified and documented (Gohar,
Khandazi & Farmani, 2012). Source of the knowledge for risk identification phase is
vital to the success of this stage and should elicit the viewpoints of experts with
extensive experience in directly dealing with similar construction projects
(Ruthankoon & Ogunlana, 2003). In this study, risk identification was accomplished
through literature review and pilot study. A total of 33 factors causing construction
waste generation were identified through literature review. Then, the identified
factors were classified into four phase of CPLC through pilot study. From that, it
presented one factor in planning phase, five factors in design phase, 32 factors in
construction phase and nine factors in finishing phase.
Risk analysis is important as it estimate risk by identifying the undesired
event, the likelihood of occurrence of the unwanted event, and the consequence of
such event. It involves measures which produce the estimation of significance level
of the individual risk factors to the project, so as to produce the estimation of the risk
of the potential factors to project success (KarimiAzari et al., 2011).
8
There are two approaches used in risk analysis, which are quantitative risk analysis
and qualitative risk analysis (Ehsan et al., 2010). Quantitative analysis involves more
sophisticated techniques and methods to investigate and analyze construction project
risks. Additionally, this analysis represents risks in mathematical form to quantify
them in terms of performance in quality, time and cost (Morledge, Smith, &
Kashiwagi, 2006). Quantitative risk analysis attempts to estimate the frequency of
risks and the magnitude of their consequences by different methods such as the
sensitivity analysis, decision tree analysis, the cost risk analysis, and Monte Carlo
simulation (Mahendra, Pitroda, & Bhavsar, 2013; Ehsan et al., 2010; Modarres,
2006)
Qualitative risk analysis assesses the impact and likelihood of the identified
risks and develops prioritized lists of the risks for further analysis or direct
mitigation. A common qualitative approach is the precedence diagramming method,
which uses ordinal numbers to determine priorities and outcomes. Another way of
employing qualitative approach is to make a list of the processes of a project in
descending order, calculate the risks associated with each process and list the
controls that may exist for each risk (Ehsan et al., 2010). A risk matrix (or a
probability/impact matrix) also is a tool commonly used in qualitative risk analysis
(Mahendra et al., 2013; Zhou & Leung, 2012; Modarres, 2006). It is a table that
contains several regions that indicate risk level based on the scale of probability and
scale of impact or severity. Risks are qualitatively assessed according to the region it
mapped. In this study, the risk levels for the factors that have been identified were
assessed by using risk matrix which has been explained in section 3.5.3.
Once the risks of a project have been identified and analyzed, appropriate risk
response strategies must be adopted to cope with the risks in the project
implementation. The treatment measures on each risk are based on the nature and
impact of the risk (Zou et al., 2007). As mentioned by Mahendra et al. (2013), risk
response can be done by several methods including risk avoidance, risk transfer, risk
mitigation/reduction, risk exploit, risk share, risk enhance, risk acceptance, and
contingency plan. In this study, to response the risk, mitigation measures for the
risky factor were proposed. The mitigation measure may reduce the probability
and/or impact of an adverse risk event to an acceptable level of risk. Taking early
action to reduce the probability and/or impact of a risk is often more effective than
attempting to repair the damage after the risk has passed (Mahendra et al., 2013).
9
Basically, eliminating construction risks seems hardly doable (Siew & Abdul-
Rahman, 2013). However, risk management should be applied into any construction
project at the initial stage of the project to get maximum benefit in managing the risk.
This is because, the awareness of the risks and appropriate strategies for dealing with
the risks are imperative and contributes to the success of the projects (Zou et al.,
2007).
2.3 Construction Wastes
There are a lot of researches in construction wastes generation that have been carried
out in various countries. It includes the types of construction wastes, factors causing
construction wastes, the impacts, and the way of handling the wastes. This subtopic
comprises the definition of construction wastes, construction wastes generation in
other countries, wastes management, and the impact of the wastes.
2.3.1 Definition
Construction wastes have been defined in various ways. Skoyles & Skoyles (1987)
stated that construction wastes is „a material which needed to be transported
elsewhere from the construction site or used on the site itself other than the intended
purpose of the project due to damage, excess or non-use or which cannot be used due
to non-compliance with the specifications, or which is a by-product of the
construction process‟. In Hong Kong, the definition of construction wastes was
established by Hong Kong Polytechnic (1993) as „by-product generated and removed
from construction, renovation, and demolition work places or sites of building and
civil engineering structures‟. In another research, construction wastes was defined as
„any material apart from earth materials, which needed to be transported elsewhere
from the construction site or used on the site itself other than the intended specific
purpose of the project due to damage, excess or non-use or which cannot be used due
to non-compliance with the specifications, or which is a by-product of the
construction process‟ (Ekanayake & Ofori, 2004). Based on the Solid Wastes and
Public Cleaning Management Act 2007 (Act 672), construction solid wastes are „any
type of solid wastes that is produced from any construction activities or demolition or
including accomplishment, arrangement, renovation or modification‟.
10
According to Poon et al. (2013), construction waste is a mixture of inert and non-
inert materials arising from various construction activities like excavation,
demolition, construction, renovation, and roadwork. Based on all highlighted
definitions, it should be understood that construction wastes is in the form of
materials losses while the construction project was being carried out.
However, according to new production philosophy, Koskela (1992) stated
that construction wastes „includes both the incidence of material losses and the
execution of unnecessary work, which generates additional costs but does not add
value to the product. This was then was supported by Formoso, Isatto, & Hirota
(1999) whom defined construction wastes as „any inefficiency that results in the use
of equipment, materials, labour, or capital in larger quantities than those considered
as necessary in the production of a building‟. This means that, besides material
wastes; time, cost, and process wastes also can be described as wastes. It can be
generated due to any inefficiency of activities such as waiting time, over production,
and processing but do not add any value to the project. However, this research only
focuses on construction material wastes. Although construction wastes generation
contributes to high economic losses than material wastes (Formoso et al., 1999), the
most important thing that we have to be concerned with is the adverse impact on the
environment (Masudi et al., 2011) which is contributed by material wastes. Table 2.1
summarizes the various definitions given for construction waste.
11
Table 2.1: Wastes definition
No. References Wastes definition
1 Skoyles & Skoyles
(1987)
A material which needs to be transported elsewhere from the
construction site or used on the site itself other than the intended purpose
of the project due to damage, excess or non-use or which cannot be used
due to non-compliance with the specifications, or which is a by-product
of the construction process.
2 Koskela (1992) Includes both the incidence of material losses and the execution of
unnecessary work, which generate additional costs but does not add
value to the product.
3 Hong Kong
Polytechnic (1993)
By-product generated and removed from construction, renovation, and
demolition work place or sites of building and civil engineering
structures.
4 Formoso et al.
(1999)
Any inefficiency that results in the use of equipment, materials, labour,
or capital in larger quantities than those considered as necessary in the
production of a building.
5 Ekanayake & Ofori
(2004).
Any material apart from earth materials, which needed to be transported
elsewhere from the construction site or used on the site itself other than
the intended specific purpose of the project due to damage, excess or
non-use or which cannot be used due to non-compliance with the
specifications, or which is a by-product of the construction process.
6 Solid Wastes and
Public Cleaning
Management Act
2007 (Act 672)
(2007)
Any type of solid waste that is produced from any construction activities
or demolition or including accomplishment, arrangement, renovation or
modification.
7 Poon et al. (2013) Construction waste is a mixture of inert and noninert materials arising
from various construction activities like excavation, demolition,
construction, renovation, and roadwork.
2.3.2 Construction Wastes Generated
The construction wastes become serious environmental problems in many countries
and are becoming more critical recently. Through literature review, issues related to
the construction wastes generation in various countries are discussed below.
Malaysia: Rahmat & Ibrahim (2007) conducted a study in the district of Johor Bharu
Tengah, Johor and reported that a total of 46 illegal dumping were found in the
investigation, with most of them discovered near the road side corridor. Forty two
percent of the wastes are actually wastes from construction. A research conducted by
Begum & Pereira (2011) found that in the Klang Valley the majority of C&D wastes
were dumped into private land or illegal dumpsites while only 20% of them were
actually disposed in legal landfills. The results also showed that 88% of the C&D
wastes generated is from residential buildings while 9% from commercial, and 3%
from government buildings, all resulting from increased demand for housing and
commercial buildings. The largest components of C&D wastes are concrete,
12
aggregate, and rubbles followed by soil, wood, metals, and roofing materials. In
2013, a research that was conducted in three construction sites found that timber
wastes was the dominant waste produced, followed by bricks, packaging wastes, and
concrete (Nagapan et al., 2013).
While, in another research, the total wastes generated at two housing project
sites was 154.31 m3 and the major wastes consists of timber (49%) (Foo et al., 2013).
Besides that, Masudi et al. (2011) conducted a study intending to quantify the
wastage level of several types of material wastes such as timber, concrete,
reinforcement bar, tiles, screeds, and plaster. The results showed that the wastage
level for major material is up to 10%. They also concluded that awareness among
construction players in Malaysia on wastes minimization is still lacking.
Thailand: As reported by a research in 2009, the construction industry generated an
average of 1.1 million tonnes of construction wastes per year between 2002 – 2005
(Kofoworola & Gheewala, 2009).
Indonesia: A research was conducted to determine quantities of construction wastes
material. The study indicated that brick and sand wastes were the most wastes on the
site which is 12.51% and 11.39% respectively. The cost modelling showed that the
range of material wastes cost was between 3.33% to 4.67% of the total material cost
(Intan, Alifen, & Arijanto, 2005).
Kuwait: Kartam et al. (2004) conducted a research to study the environmental
management of C&D wastes. The results indicated that C&D wastes in Kuwait
consist of concrete (30%), bricks (30%), sand (25%), wood (8%), steel (5%), and
others (2%). According to statistics and assumptions, the total C&D wastes
production was estimated to be 1.6 million ton/year (excluding solely earth and
sand).
China: In Shenzhen, a research was carried out to investigate the source of
construction wastes generation. According to the survey results, concrete, cement,
brick, timber, tile, steel, and aluminium wastes are the main wastes source produced
at construction sites (Wang et al., 2008). Another research found that Wastes
Generation Rate (WGR) ranged from 3.275 to 8.791 kg/m2 while miscellaneous
13
wastes, timber for formwork and false work, and concrete were the three largest
components amongst the generated wastes (Lu et al., 2011).
Based on literature review, it can be seen that construction waste generation
problem not only occur in Malaysia but also in other countries. It also can be
concluded that construction waste is commonly contributed by timber, brick,
concrete, sand, steel, and others, with majority of the wastes disposed into landfills.
However, the amount of waste generated varies in each country. Table 2.2
summarizes the construction waste generated for the countries mentioned above.
Table 2.2: Construction wastes generated
Origin Reference Findings
Malaysia Rahmat & Ibrahim,
2007 A total of 46 sites of illegal dumping were found in the District
of Johor Bahru Tengah, Johor.
Most of illegal dumping sites were located near the road side
corridor.
42% of the wastes originated from the construction industry.
Begum & Pereira,
2011 Only 20% of C&D wastes were disposed in legal landsites
88% C&D wastes were generated from residential buildings,
9% from commercial buildings, and 3% from government
buildings.
Masudi et al., 2011 Wastage level for major material is up to 10%.
Awareness among construction players in Malaysia on wastes
minimization is still lacking.
Foo et al., 2013 Total waste generated at two sites was 154.31 m3 and 49%
were timber wastes.
Thailand Kofoworola &
Gheewala, 2009 1.1 million tonnes of construction wastes were generated per
year between2002-2005.
Indonesia Intan et al., 2005 Brick and sand were the dominant wastes (12.51% and
11.39%)
Wastes generated in the range of 3.33% to 4.67% of the total
material cost.
Kuwait Kartam et al., 2004 Wastes in Kuwait consist of concrete (30%), bricks (30%),
sand (25%), wood (8%), steel (5%), and others (2%).
1.6 million ton/year construction wastes generated.
China Wang et al., 2008 Concrete, cement, brick, timber, tile, steel, and aluminium
wastes are the main wastes sources produced at construction
sites.
Lu et al., 2011 Wastes Generation Rate (WGR) ranged from 3.275 to 8.791
kg/m2.
2.3.3 Waste Management
Construction waste issues are one of the prevailing global problems that require
serious attention. The implementation of construction waste management hierarchy
can help to handle and manage construction waste generation. Nagapan et al. (2012d)
14
suggested that this adoption can be integrated into a six stage of waste management
hierarchy which includes prevention, minimization, reuse, recycling, recovery, and
disposal, as shown in Figure 2.1.
Figure 2.1: Six stage of waste management hierarchy
(Adapted from Nagapan et al., 2012d)
Figure 2.1 shows the six stages of waste management hierarchy that can be
adopted to handle the wastes. The stage of the waste management option is ranked
based on what is best for the environment. The most preferred way is by preventing
or reducing the generation of waste. However, if the waste generation cannot be
prevented or reduced, it is recommended to recycle, reuse or recover the wastes as
much as possible. But, if wastes are still being produced, then the last option is by
disposing the wastes. However, the disposal method is not a preferred option because
the role of waste management is to reduce the amount of waste that is discharged into
the environment (Nagapan et al., 2012d). Below is the description for each stage of
waste management hierarchy.
Prevention& Minimization: It refers to avoid or reduce producing waste, which is
the best way to reduce the impact of waste on the environment (Egan, 1998;
Ekanayake & Ofori, 2004; Esin & Cosgun, 2007) and for better economic savings
(Al-Hajj & Hamani, 2011). Besides that, avoiding or minimizing from the source in
construction project may reduce the amount of waste generation (Kozlovská &
Minimization
Reuse
Recycling
Recovery
Disposal
Prevention
Most preferable
15
Spišáková, 2013), raw material usage, and lessen transportation works (Nagapan et
al., 2012d).
In order to prevent or minimize the generation of construction waste, a proper
construction waste management approach should be planned before site operations
begin. As stated by Lu & Tam (2013), contractors have to prepare a waste
management plan as part of the overall environmental management plan, and set out
waste reduction targets and programs. They also are advised to set up a good house-
keeping practice and a waste management monitoring and audit program, throughout
the whole construction processes (Lu & Tam, 2013). Al Hajj & Hamani (2011) have
suggested four measures for efficient prevention of construction waste on site which
are logistics management, supply chain management, modern construction method,
and training and incentivizing.
In China, the government has taken various actions to tackle the issue of the
increasing amount of construction waste generation. These actions include the
alteration of the Waste Disposal Ordinance, issuance of a policy paper for a
comprehensive 10 year plan to reduce construction waste, launching of a green
manager scheme on construction sites, promulgation of a waste reduction framework
plan, issuance of a practice note promoting the use of recycled aggregate,
implementation of the policy of Waste Management Plan (WMP) at construction
sites, commissioning of a pilot concrete recycling plant, and introduction of a
charging scheme for the disposal of construction waste (Esin & Cosgun, 2007).In
Malaysia, the implementation of prefabrication and Industrialized Building System
(IBS) method in the construction industry was encouraged by the government as a
solution to reduce the amount of waste generation (Abdullah & Malik, 2012). The
adoption of this method can reduce construction waste generated by as much as 41%
to 50%, which is a large amount of reduction (Hassan et al., 2012; Begum, et al.,
2010). Though preventing waste production on site is not possible, we can, however,
reduce its amount.
Reuse: It can be defined as using the same material in construction more than once,
including using the material again for the same function (e.g., timber formwork in
construction). Various countries use this approach to reduce the amount of waste
generated before it gets disposed in landfill. In China, the government implements
the Construction Waste Disposal Charging Scheme (CWDCS) to encourage
16
contractors to recycle and reuse their construction waste and this scheme has shown a
significant reduction even after three years of implementation (Yu et al., 2013).
In Germany, a technology of drying distillation and burning is used to handle
waste which will separate every kind of material that can be reprocessed cleanly
from waste and reused again (Wang & Li, 2011).Besides that, some materials such as
timber can be reused in the site for several times to avoid the cost of collection and
disposal, and the extra cost of virgin material. Broken bricks and concrete can still be
reused as a sub-grade of access road to the construction site (Nagapan et al., 2012d).
This approach could help to reduce construction waste at site before it gets disposed.
Recycling: Recycling means separating, collecting, processing, marketing and
ultimately using a material that would otherwise have been thrown away (Yeheyis et
al., 2012). A study has shown that recycling reduces the amount of waste, Green
House Gas (GHG) emission, saves energy, and reduces the use of virgin raw material
(Pimenteira et al., 2005). Various countries have practised recycling very well in
order to reduce the amount of waste. In Denmark, Estonia, Germany, Ireland, and the
Netherlands the percentage of recycling rate is more than 80% while in France and
Luxembourg the recycling rate percentage is between 40% to 50% (Calvo et al.,
2014).
In Finland, the recycling rate of the C&D wasteincreasedto70% as the
government imposed garbage tax to 30 euro per tonne in 2005 and planned on
increasing the tax further more recently (Yunpeng, 2011). In Holland, the
government had set up a series of laws of restricting dumping of waste and quality-
control system of forcing recycling. The government also motivated contractors to
recycle their waste by granting reward bonus if they used recycled materials in their
project. However, the recycling rate of construction waste in Malaysia is still low at
10.5% (Solid Waste and Public Cleansing Management Corporation (PPSPPA),
2013), due to the lack of awareness among construction players (Goh et al., 2013;
Masudi et al., 2011).
Recovery: It can be defined as the removal of materials or components from the
waste stream in a manner to keeps in original form for reuse in the similar form as it
was produced. In Germany, the incineration technology has assisted the recovery of
metal waste. This recovery tool will cut off until two to three kilograms of harmful
17
heavy metal in one tonne wastes after distillation and burning process. Thus, this
method resolves the problem effectively from taking up space at the landfill.
Moreover, the gas produced during the handling process is used to generate
electricity.
Disposal: The most common disposal of material waste is by landfill (Nagapan et al.,
2012d). This is the final option used for construction waste disposal. However, it is
advised to dispose properly at a landfill to alleviate pollution to the surrounding. In
Malaysia, the practice of construction waste management is still low as compared to
other countries. Most of the waste ends up at landfills. It can be seen in Malaysia that
about 261 to 291 landfill sites are in existence (Hamatschek, Tee, & Faulstich, 2010).
Also in Thailand, most of construction waste are buried on site, disposed at landfill
or illegally dumped. Reuse and recycle are less frequently practiced since the
processing cost exceeds the cost of buying raw material (Manowong, 2012).
As a conclusion, it is seen that a waste management hierarchy offer a
systematic and efficient waste management strategy which would minimize the
generation of waste at different level. A waste management hierarchy should be
applied in any construction project. The construction parties involved should try to
prevent, reduce, reuse, and recycle the construction waste before it dispose to
landfills. The approach will helps to reduce negative issues related to environment,
social and economy.
2.3.4 Impacts of the Waste
Some amount of the material used in the construction project generally will end up as
waste (Hasan et al., 2013). Various researches have revealed that the impacts of
construction waste generation are not only on the environment, but also on the
economic and social aspects (Marzouk & Azab, 2014; Nagapan et al., 2012d; Yuan,
2012). Wastes are usually disposed in landfills and this disposal significantly impacts
the environment. There are many types of environmental impacts associated with
construction waste generation, including the pollution of air, water, noise, and land;
ecology damage; loss of raw materials; and increased illegal dumping.
18
According to Marzouk & Azab (2014), the environmental problems due to
waste generation include diminishing landfill space due to incremental quantities of
these disposed wastes in it, depleted building materials, increase in contamination
from landfills that leads to serious negative health effects, damage to the
environment, and increase in energy consumption for transportation, and
manufacturing new materials instead of those materials dumped and which require
energy production. Another study revealed that the effects of construction waste on
the environment are clear (Spies, 2009). It can cause water and soil pollution, air
pollution, climate change, and adverse effects on flora and fauna. As mentioned by
Laquatra (2004), the negative effects of construction waste on the environment
includes landfill space becoming limited, faulty landfills polluting the air, earth, and
water, and increase in illegal dumping of C&D waste. This shows that the majority
of researchers have a consensus that the significant impact on the environment due to
improper waste disposal is environmental pollution.
Production of waste can also affect the cost of project. As much as wastes are
generated, the more the cost is needed to dispose them. According to Marzouk &
Azab (2014), due to the production of construction waste, large amount of money is
needed to be spent for dumping wastes in landfills, and for controlling the effect of
dumping to the environment. Sometimes, the contractors would have to pay twice for
the material cost and landfill fees. Then, they would pass the cost to homebuyers in
the form of increased house price (Laquatra, 2004). On the other hand, as
construction waste impacts the environment, it can also spoil the public health. Air
pollution may cause various respiratory diseases such as asthma, heart cancer, and
lung cancer especially to the children and senior citizen (Marzouk & Azab, 2014).
Table 2.3 shows the mapping of impacts of construction waste generation which is
constructed based on literature review.
19
Table 2.3: Mapping of impact of construction waste
Category Impact of Construction Waste
Reference
Fre
qu
ency
1 2 3 4 5
Na
ga
pa
n e
t a
l. (
201
2)
Ma
rzo
uk
& A
za
b (
20
14
)
La
qu
atr
a (
20
04
)
Sp
ies
(20
09
)
Lu
et
al.
(2
011
)
Environment
Environmental pollutions / / / / / 5
Shortage of land / / /
3
Increasing of illegal dumping /
/
2
Severe ecological damage / /
/
3
Increase contaminant in landfill
/
1
Climate change
/
1
Loss of raw materials
/
1
Economic
Increase in transportation charges of CW /
/
2
Increase cost of project /
/
2
Increase in landfill fee /
1
Increase price of raw materials /
1
Delay of projects /
1
Economic losses / /
2
Social Dangerous to the people's health / /
2
Negative effect to the society /
1
2.4 Causative Factors of Construction Waste Generation
As waste impairs the efficiency, effectiveness, value, and profitability of construction
activities, there is a need to identify the causes of wastes generation and to control
them within reasonable limits. Wastes in construction projects can occur due to many
reasons. The comprehensive literature reviews on causative risk factors regarding
construction wastes generation are carried out to understand these issues.
Malaysia: According to Hassan et al. (2012) which conducted a study in the
Northern Region of Malaysia regarding the factor causing construction wastes
generation has found that the factors that have the highest mean responses through
the questionnaires survey are „Traditional construction method‟, „Poor
workmanship‟, „Poor storage‟, „Poor handling‟, „Untidy construction site‟, and „Lack
of management techniques to minimize waste‟. Another study which was also
conducted in Malaysia has found that five significant factors causing construction
20
wastes generation are „Poor site management or supervision‟, „Lack of experience‟,
„Inadequate planning and scheduling‟, „Mistakes and errors in design‟, and „Mistakes
during construction‟ (Nagapan et al., 2012c).
China: Yunpeng (2011) investigated the main causes of the generation of
construction wastes and they are „Unimplemented wastes management measures and
weak consciousness of material saving and environmental protection‟, „Low
performance of building materials and backward construction technologies‟, „Lack of
communication and coordination between building contractors‟, and „No irritation of
market benefit and short of supervision‟.
Singapore: Ekanayake & Ofori (2004) have carried out a survey to determine the
attributes according to their potential contributions to the generation of waste on site.
The finding shows that under Design-related waste sources, four of the attributes
have most significant impacts on construction wastes generation on site were „Lack
of attention paid to dimensional coordination of products‟, „Design changes while
construction is in progress‟, „Designer‟s inexperience in method and sequence of
construction‟, and „Lack of knowledge about standard sizes available on the market‟.
Under the Operational sector, the three attributes that had most significant impact on
construction wastes generation at site are: „Errors by trades persons or labourers‟,
„Damage to work done due to subsequent trades‟, and „Required quantity unclear due
to improper planning‟. Six attributes under Material handling related waste sources
and only one is the most significant impact which is „Inappropriate site storage‟.
There were three attributes under Procurement and none of the attributes
significantly contribute to construction wastes generation.
United Kingdom: Osmani et al. (2008) carried out a study to investigate the
architects‟ perspectives on construction wastes reduction by design. The findings
reveal that waste management is not a priority in the design process. Additionally,
the architects seem to take the view that wastes are mainly produced during site
operations and are rarely generated during the design stages; however, about one-
third of construction wastes could essentially arise from design decisions.
21
India: A research conducted by Kulatunga et al. (2006) using questionnaires survey
to study the attitudes and perceptions of construction workforce on construction
wastes in Sri Lanka. The findings indicated positive perceptions and attitudes of the
construction workforce towards minimizing wastes and conserving natural resources.
However, a lack of effort in practicing these positive attitudes and perceptions
towards waste minimisation was identified.
Indonesia: Nazech, Zaldi, & Trigunarsyah (2008) also discussed the results of the
study on the identification of construction wastes in road and highway construction
projects in the greater Jakarta area. The study indicates that Work Execution has
been identified as the most important group of causes of the construction wastes
which „Inadequate proper construction equipment‟ has been suggested as the main
contributor to this condition. The other dominant sources of wastes are Materials and
Manpower. The study also shows that „Lack of management capability‟ as the main
factor of the construction wastes, which indicates the correlation between the waste
produced and management aspects related to project duration and labours.
Egypt: Garas, Anis, & Gammal (2001) whom conducted a research to address the
incidence of material waste in the Egyptian Construction Industry has found that the
most dominant causes are late information, uncompleted design, inadequate
information, poor control, unnecessary people‟s moves, untrained labour, work not
done, poor technology of equipment, changes to design, and damage during
transportation.
Botswana: Urio & Brent (2006) investigated construction waste in the Francistown
area of Botswana as a case study. The identified causes of construction wastes on the
sites are „Lack of onsite WMP‟, „Wastes from application process‟, „Overmixing of
material due to the lack of knowledge of requirements‟, „Error by tradesperson or
labourer‟, „Cutting uneconomical shapes/length‟, „Damage caused by subsequent
trades‟, „Change to design‟, „Use of incorrect material‟, „Damage during
transportation on site‟, „Inclement weather‟, „Order error‟, „Contract document
incomplete at time of construction commencement‟, „Error in contract document‟,
„Over-ordering‟, „Inappropriate storage on site‟, „Damage during transportation to
22
site‟, „Accident, supplier error‟, „Criminal wastes due to damage or theft and
equipment malfunction‟.
Turkey: A research was conducted by Polat & Ballard (2004) to study the main
waste causes in the Turkish construction industry. The significant causes of material
waste that were found are „Ordering of materials that do not fulfil project
requirements defined on design documents‟, „Imperfect planning of construction‟,
and „Workers mistakes during operation‟.
Nigeria: Wahab & Lawal (2011) have conducted a research to assess the forms,
causes, and factors incidental to wastes. The result shows that among the factors
incidental to wastes, „Last minute client requirement‟ was ranked highest as the
factor that leads to design variation.
Based on past researches, it can be seen that there are various factors that
contribute to generation of construction wastes. The factors also vary in each
country. As such, a mapping of various factors causing construction wastes
generation was constructed. In order to adopt these factors in accordance to the
Malaysian construction industry, a total of 33 factors are chosen as the causative
factors in this research. The factors are classified into seven groups which are
Information and Communication (ICT), Equipment (EQP), Project and Contract
Management (PCM), Material (MAT), Delivery/Procurement (DEL),
External/Unpredictable (EXT), and Human Resources/Manpower (HRM). The
mapping of the 33 factors causing construction wastes generation according to
previous study is shown in Table 2.4. The description for each factor can be referred
in Appendix D.
23
Table 2.4: Mapping of factors contributing construction wastes generation
No
COUNTRY
REFERENCES
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
MA
L
MA
L
MA
L
MA
L
CH
N
CH
N
CH
N
CH
N
CH
N
CH
N
CH
N
CH
N
SN
G
UK
UK
INS
IND
EG
P
BS
W
TK
Y
NIG
NIG
NIG
NIG
GH
N
GR
C
AS
D
BR
Z
TH
D
FACTORS CONTRIBUTING TO
CONSTRUCTION WASTES
Ha
ssa
n e
t a
l. (
20
12)
Na
ga
pa
n e
t a
l. (
201
2b
)
Ika
u e
t a
l. (
201
3)
Ma
sud
i et
al.
(2
01
1)
Lu
et
al.
(2
011
)
Wa
ng
et
al.
(2
008
)
Ta
m e
t a
l. (
200
7a)
Ta
m e
t a
l. (
200
7b
)
Wa
n e
t a
l. (
20
09)
Yu
np
en
g (
20
11)
Sh
en e
t a
l. (
20
02
)
Po
on
et
al.
(2
00
4)
Ek
an
ay
ak
e &
Ofo
ri.
(200
4)
Osm
an
i et
al.
(2
008
)
Do
min
go
et
al.
(2
008
)
Na
zech
et
al.
(20
08)
Su
rve
& K
ulk
arn
i (2
01
3)
Ga
ras
et a
l. (
200
1)
Uri
o &
Bre
nt
(20
06
)
Po
lat
& B
all
ard
(2
00
4)
Wa
ha
b &
La
wa
l (2
01
1)
Ola
dir
an
& J
ose
ph
(2
00
9)
Ad
ewey
u &
Ota
li (
20
13)
Jo
hn
& I
tod
o (
20
13
)
Ag
yek
um
et
al.
(2
01
2)
Pa
no
s &
Da
na
i (2
012
)
Al
Ha
jj &
Ha
ma
ni
(20
11)
Fo
rmo
so e
t a
l. (
200
3)
Ko
fow
oro
lo &
Gh
eew
al
(20
09
)
Information and Communication (ICT)
1 Poor coordination between parties / / / / / / / /
2 Poor quality of information / / / / / / /
3 Delay in information flow among parties / / /
Equipment (EQP)
4 Equipment failure / / / / / / /
5 Shortage of equipment / /
6 Unsuitable tools used / /
Project and Contract Management (PCM)
7 Lack of wastes management plans / / / / / / / / /
8 Rework / / / / / / / / /
9 Error in contract documentation / / / / / /
10 Mistakes in quantity surveys / / / / /
11 Last minute client requirements / / / / /
24
Table 2.4 (continued) 12 Inexperience designer / / /
13 Lack of legal enforcement / /
Material (MAT)
14 Ordering errors / / / / / / / / / / / / / / /
15 Items not in compliance with specification / / / / / / /
16 Poor quality of materials / / / / / /
17 Inappropriate use of materials / / / / /
18 Inventory of materials not well
documented / / /
19 Vandalism at site / / / /
Delivery/Procurement (DEL)
20 Damage during transportation / / / / / / / / / / / / / / /
21 Wrong material delivery procedures / / / /
22 Supplier errors / /
External/Unpredictable (EXT)
23 Effect of weather / / / / / / / / / / /
24 Accident at site / / / / / / /
25 Damage caused by workers / / / / / /
26 Damages caused by third parties / /
27 Unforeseen ground conditions /
Human Resource/Manpower (HRM)
28 Poor attitudes of workers / / / / / / / / /
29 Insufficient training for workers / / / / / /
30 Poor workmanship / / / / / /
31 Lack of experience / / /
32 Lack of enthusiasm among workers / /
33 Lack of knowledge about construction / / /
*Note: MAL: Malaysia; CHN: China; SNG: Singapore; UK: United Kingdom; INS: Indonesia; IND: India; EGP: Egypt; BSW: Botswana; TKY: Turkey; GHN:
Ghana; ASD: Arab Saudi; BRZ: Brazil; THD: Thailand
76
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Bumiputera and Non-bumiputera Industrialized Building System (IBS)
contractors in Selangor. 2012 International Conference on Statistics in Science,
Business and Engineering (ICSSBE) (pp. 1–6). IEEE.
Adeweyu, T. O., & Otali, M. (2013). Evaluation of causes of construction material
wastes - Case of Rivers State, Nigeria. Ethiopian Journal of Environmental
Studies and Management, 6(6), 746–753.
Agyekum, K., Ayarkwa, J., & Adinyira, E. (2012). Consultants‟ perspectives on
materials wastes reduction in Ghana. Engineering Management Research, 1(1),
138–150.
Akintoye, A. S., & Macleod, M. J. (1997). Risk analysis and management in
construction. International Journal of Project Management, 15(1), 31–38.
Al-Hajj, A., & Hamani, K. (2011). Material wastes in the UAE construction
industry : Main causes and minimisation practices. Architectural Engineering
and Design Management, 7(4), 221–235.
Alshubbak, A., Pellicer, E., & Catalá, J. (2009). A collaborative approach to project
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