Cost Overruns and Stakeholder Roles in Construction Projects: A Review

This report examines the issue of cost overruns in construction projects, a chronic problem in the industry. It delves into the roles and responsibilities of key stakeholders, including clients, consultants, and contractors, in managing these overruns. The research, based on a literature review and industry inputs, identifies 73 attributes related to cost performance. Planning and scheduling deficiencies are found to have the highest impact, with robust control procedures, adequate programming, efficient design, and effective site management being critical factors. The client's role in facilitating effective management of these factors is also crucial. Multivariate regression analysis highlights the influence of five significant factors on managing cost overruns. The findings aim to bridge a knowledge gap by shifting priorities in cost estimation and management practices across all industry sectors. The report also includes a literature review of factors affecting cost performance, such as poor site management, decision-making speed, and client-initiated variations, emphasizing the need for a comprehensive understanding of stakeholder responsibilities to improve cost performance.

Cost Overruns and Failure in Project
Management: Understanding the Roles
of Key Stakeholders in Construction Projects
Hemanta Doloi1
Abstract: The subjectof poorcostperformance has been widely published in the mainstream projectand construction management
literature. Nevertheless, the underlying responsibilities of the key stakeholders (clients, consultants, and contractors) in
problem in the Australian construction industry remain unclear. By performing an in-depth analysis of the roles and resp
key stakeholders, this research is intended to unfold the industrywide perception of cost performance being heavily relia
performance alone.Based on a thorough literature review and relevantindustry inputs,73 attributes associated with costperformance
were identified for investigation.Based on the relative importance weighing technique on 48 selected attributes,planning and scheduling
deficiencies have the highest impact on cost performance from clients, consultants, and contractors’ perspectives. Confi
sis on the combined responses across all three groups suggests that robust control procedures and adequate programm
design and effective site management,are the mostcriticalfactors.These factors are primarily associated with the responsibilities o
contractors and consultants for managing cost overruns in projects. However, the client’s responsibility in facilitating eff
of these factors within the project environment is crucial. Multivariate regression analysis performed on eight factors’ sc
influence of five significant factors (p < 5%) on managing cost overruns. The findings are expected to abridge a significa
shifting the priorities in costestimation and managementpractices across allindustry sectors.DOI: 10.1061/(ASCE)CO.1943-7862
.0000621.© 2013 American Society ofCivil Engineers.
CE Database subject headings: Construction costs; Estimation;Projectmanagement.
Author keywords: Costoverrun;Costestimation;Costperformance; Projectmanagement.
Introduction
The factors thatinfluence costduring the conception and design
phases within the construction process have been widely investi-
gated, primarily based on the contractor’s cost-estimating practices
(Akintoye 2000; Cheung et al.2008).Hicks (1992) revealed that
regardless of management competence and the financial strength of
the contractor, accurate cost estimation at an early stage is the key
to avoid cost overrun in projects (Hicks 1992). Cost estimation is a
technicalprocess of predicting expenditure,and success depends
on accurate integration of project information, resources, and con-
trolover projectimplementation (Baloiand Price 2003).Factors
influencing cost performance based on initial estimates have been
widely published and primarily concern project complexity,tech-
nology requirements,vagueness in scope,and the projectteam
requirements (Mansfield etal. 1994;Akintoye 2000;Frimpong
et al. 2003; Love et al. 2005). Empirical evidence suggests that con-
tractors’ efficiency in the estimating process and appropriate tender
pricing depictsthe cost performancein construction projects
(Skitmore and Wilcock 1994). Therefore, contractors’ ability in us-
ing sophisticated methods and their rationalizations atthe tender
development stage are considered crucial in achieving cost success
in mostprojects (Green 1989).In many instances,all of these
factorsidentified atan early stage ofthe construction process
are described as uncontrollable risks (Akinciand Fischer 1998).
Appropriate consideration ofthese uncontrollable risksduring
the initialstage ofthe estimating phase significantly increases
the chance ofminimizing any mistakes overthe course ofthe
construction phase. However, some of the key questions regar
responsibility,deliberation,and managementof such risks in the
construction supply chain remain unclear in the discipline dom
Identification ofthe cost-related risks,underlying drivers,and
impediments foreffective managementmustbe assessed in the
contextsof threekey stakeholders:clients,contractors,and
consultants.
This research is intended to investigate the perceived unde
standing and importance of the key attributes among these th
key stakeholders’ groups with respect to achieving the target
performance in projects.Estimation of projectcosts atthe early
stages of the design process and the ability to manage these c
throughout the construction phase is paramount to a project’s
all success. Past research illustrates that construction cost ove
and the subsequent poor cost performance are the attributes
lack of understanding among allparticipating teams across the
construction industry (Akintoye 2000;Frimpong etal. 2003).
However,an accurate understanding ofthe key attributes in the
context of the responsibility and management ability among c
and consultantcontractors has notbeen explored.By identifying
the factors affecting costoverruns,this research highlights the
criticality fortheireffective managementwithin the rolesand
responsibilitiesamong clients,consultants,and contractorsin
construction projects.
1Senior Lecturer, Faculty of Architecture, Building and Planning, Univ.
of Melbourne,Victoria 3010,Australia.E-mail:[e-mail]
Note. This manuscript was submitted on November 13, 2009; approved
on June 6, 2012; published online on July 25, 2012. Discussion period open
until August 1, 2013; separate discussions must be submitted for individual
papers. This paper is part of the Journal of Construction Engineering and
Management, Vol. 139, No. 3, March 1, 2013. © ASCE, ISSN 0733-9364/
2013/3-267-279/$25.00.
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Literature Review
Over the last few decades,there has been much research into the
factors thataffectcostperformance in the construction phase of
projects.Usually the vastmajority of costoverruns occur during
the construction phase, in which many unforeseen factors are con-
ceived over the conception/design stages (Chan and Kumaraswamy
1997).Attributes such as poor site management and supervision,
low speed of decision-making and client-initiated variations have
reportedly been some of the most significant causes of cost over-
runs in the construction phase of projects (Trostand Oberlender
2003;Iyer and Jha 2005).These factors primarily relate to the
project manager, given that project management involves managing
resources such as workers,machine,money, materials,and meth-
ods during this period (Frimpong etal. 2003).However,precise
understanding of these factors and protocols of responsibility shar-
ing for effective managementamong the key stakeholders is not
widespread. Although tools and techniques implemented to control
these factors is perceived to play an important role, understanding
the root cause of these factors and their potential impacts in man-
aging them from the perspectives of clients, consultants, and con-
tractors is the key for achieving success in costperformance.
Despite the factthatfactors associated with costmanagement
are reasonably understood,improvementof construction industry
practices in terms of responsibility sharing and deliberations among
the project’s participants is not particularly evident.In the United
Kingdom,Green (1989) conducted six case studies of tendering
practices for establishing the reasons for disregarding the best prac-
tices among the industry. Green (1989) concluded that whereas the
rationality for estimating is justified across the firms,a range of
uncertainties associated with the wider environmental issues prevail
over the tendering process. In an attempt to understand the rationale
of estimating indirect costs for construction work, Tah et al. (1994)
investigated the currentpractices towards quantification and allo-
cation of general overheads, risk contingencies, and profit margin
across seven firms. The research revealed that the approach for such
estimation is ad-hoc and based on past experience alone (Tah et al.
1994).Whereas more sophisticated and reflective approaches to-
wards subjective practices were suggested in published research,
the relationshipsbetween subjective practicesand overallcost
performance were notclearly highlighted (Enshassiet al. 2009;
Akintoye 2000).In the United Kingdom,Skitmore and Wilcock
(1994) surveyed nine smaller builders involved in all types of build-
ing projects to ascertain the pricing mechanism in preparing a bill
of quantities for competitive tender.The bulk of the items were
priced by experience,excepta smallpercentage ofspecialized
items,which were priced by the prescribed detailed methods.
However,the research asserted thatthe combination of both the
subjective and prescribed methods is the mostefficientmanner
in which achieving accurate tenderpricesfor estimatorsin a
time-constrained environmentcan be achieved.Incorporating the
statistically significant variability of the estimates in the program
evaluation and review technique (PERT) can enhance the reliability
of the subjective estimates.However,exclusion ofcostperfor-
mance in relation to such assertions rendered this research insuffi-
ciently comprehensive.
Chan and Kumaraswamy (1997) reported five principal causes
of time overruns perceived among clients, contractors, and consul-
tants in Hong Kong construction projects. A questionnaire survey
was designed comprising 83 delay factors across eight categories
and distributed to 400 localfirms involved in construction activ-
ities.Based on a 37% response,the five most significant sources
of delay were poor site management and supervision,unforeseen
ground conditions,low speed in decision-making,client-initiated
variations,and design change.Whereas a reasonable agreement
among three groups was reported on these time related factor
and theirlinks to overallprojectsuccess,the findings failed to
establish any meaningful insights into the roles and responsib
of the three groups and their underlying impacts on the overa
performance of the project.
Based on data collected from 84 contractors firms in the Un
Kingdom, Akintoye (2000) reported the primary factors releva
cost estimating practice as project complexity,scale and scope of
construction, market conditions, methods of construction, site
straints, client’s financial position, buildability, and location of
project.However,an investigation on how such factors would be
perceived by clients and consultants, and their potential impa
overall cost performance of projects,was not performed.This re-
search was therefore insufficiently comprehensive.Investigating
the causes of substantial cost variations relative to the initial c
tract and excessive cost overruns in Nigerian construction pro
Mansfield etal. (1994)revealed thatpoorprojectmanagement
during the construction phase produces notonly the deficiencies
in the projects’ plan and cost control, but also jeopardizes the
outcomes expected by clients,contractors,and consultants in the
overalldevelopmentprocess.Although the technicalability of
project managers is an important element to the project’s suc
the contribution of contractors and consultants in the process
cost monitoring and controlling is equally important in achievi
overallsuccess in projects (Iyer and Jha 2005).
In an attemptto establishing a predictive modelfor early cost
estimation, Trost and Oberlender (2003) collected quantitative
across 45 potential drivers on 67 completed construction proje
across the world. Based on factor analysis and regression mod
basic process design and site requirement was concluded to b
mostsignificantfactor thatimpacts estimate accuracy.Although
this finding is an important first step in that it reveals the sign
cance of early cost estimation, the exclusion of building and in
structure sector in the data collection process rendered the re
constrictive in the context of cost performance across constru
projects. Addressing the risk issues that affect cost performan
a project level, Baloi and Price (2003) examined the normative
behavioral perspectives based on an existing literature search
discussion with construction contractors.A lack of mechanized
support, such as a decision support system and contractors’ e
rience,were reported to be the key causes for failure in cost pe
formance in mostprojects.However,the rolesof clientsand
consultants were notincluded in the costperformance analysis,
and thus such findings are notbroadly useful.
Based on the case study data on completed projects in Gha
Frimpong etal. (2003)identified five key factorsthatimpact
projectcost performance.These factorsare monthly payment
difficulties from agencies,poor contractor management,material
procurement,poor technicalperformance,and escalationof
materials prices.Although a generalconsensus of the impacts of
these factors on cost performance was found among clients,con-
tractors,and clients,a significant contrast was highlighted on the
issues reported previously (Baloiand Price 2003;Skitmore and
Wilcock 1994).
Based on an investigation of the transport infrastructure acr
258 rail,bridge,tunnel,and road projects in Denmark,Flyvbjerg
et al. (2004) highlighted three key factors that affect cost over
Flyvbjerg etal. (2004)asserted thata longerprojectimple-
mentation phase, larger project size, and public ownership fac
are highly susceptible to costoverruns.However,relationships
between clients,contractors,and consultants in addressing these
factors and minimizing the impact of cost overruns were exclu
in the investigation. Cheung et al. (2008) investigated the atti
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clients and estimators towards estimating errors in the estimating
practice in the Hong Kong construction industry. Based on a ques-
tionnaire survey conducted among 45 estimators,33 clients,and
regression modeling,tolerances in overestimations among both
partieswere highlighted.Although both estimatorsand clients
are reasonablysatisfiedwith overestimations,the underlying
causes ofsuch practices and strategies formitigation were not
revealed.
As evident from the previously discussed research, the field of
costmanagementand underlying attributes in costestimation is
reasonably well developed (Bowen and Edwards 1998). However,
it is unclear how each of the attributes relate to the clients,con-
sultants,and contractors,and how the attributes effectsuccessful
costperformance.Currently,no research has been found in the
public domain thatfocuseson the entire projectdevelopment
phase,using the perceptions of clients,consultants,and contrac-
tors,and how itimpacts costperformance (Fortune 2006).There
is a need to re-think and re-engineer the existing or normalcost
estimating process, incorporating emergent diversity and complex-
ity,especially in the projectdelivery approach.The findings of
this research should benefit the construction community by high-
lighting thekey factorsthatimpactcostsand theassociated
responsibilities for effective managementamong the key project
participants.Additionally,the results willprovide guidance for
further research in developing practicalsteps thatcan be imple-
mented to reduce costoverrunsduring the entire development
process.
Methodology and Approach
Cost performance of projects and the management of cost overruns
is an ongoing topic of investigation in many countries.There has
been much research into the generic causes of costperformance
issuesover the designand constructionaspectsof projects
(Skitmore and Wilcock 1994;Cheung etal. 2008).However,no
or little research has been reported in the context of understanding
the rootcauses,tackling mechanisms,and stakeholders’ respon-
sibilities in addressing this chronic issue of costoverrun in most
projects.Furthermore,the area-specific study ofthe factors that
affectcostperformance in projects renders pastfindings insuffi-
ciently comprehensive in relation with Australian industry practice
(Love etal. 2005).Focusing on Australian construction projects,
this research istherefore intended to examine the rootcauses
behind the poorcostperformance from the perspectives ofthe
three key participants and management responsibilities commensu-
rate to the contractual roles of these participants across the entire
developmentprocess.
The research is intended to expand currentunderstanding of
cost performance issues and management methods through a ques-
tionnaire survey.The questionnaire was designed to capture the
currentconstruction industry experiences among clients,consul-
tants,and contractors.Over 160 construction clients,consultants,
and contractors were selected on the basis of their diverse back-
grounds,professionalexperiences,and currentparticipation in
the industry.
The objective ofthis research is to identify the mostcritical
factors that impact cost performance across the design consultants,
contactors,and clientperspectives by the following:
• Ranking the most critical attributes based on the relative impor-
tance weight(RIW),
• Reduce the influencing attributes into factor groups, identifying
the latent properties of each factor and their effective manage-
mentbased on factor analysis,
• Investigate the influencing factors on cost performance bas
multivariate regression analysis,and
• Analyze the management of the influencing factors in relati
with the roles and responsibilities of the consultants, contac
and clientin the project.
The first objective is important for clients, consultants, and
tractors to understand and attend to the underlying attributes
impactcostsuccess.By establishing the relative positioning of
the attributes in the order of their significance, the second obj
attempts to create a better understanding of the clustered eff
(e.g., factors) of these attributes on project cost performance.
factors are then analyzed in the context of effective managem
among the clients, consultants, and contractors in the optimal
delivery process.The second objective is particularly important
for allthree parties to prioritize,specifically,the factors in terms
of theircriticality fordeveloping contractualarrangements and
assume responsibilities, to obtain the desired outcomes.The third
objective is intended to validate the factors in terms of their re
and underlying influence on cost performance in projects. Fina
through the fourth objective, the resulting factors are analyzed
reference to the roles and responsibilities of all three key stak
ers with respect to cost management processes and their effe
development and implementation in the construction projectsBy
increasing the discipline-specific knowledge in meeting the req
ments and expectations of clients,consultants,and contractors,it
may be possible to accurately highlight the advantages and di
vantages of the cost management approach and clarify the pe
viewpoints within the construction industry.
The research uses a carefully designed questionnaire to col
the perceived opinions of the most possible causes of cost ove
among the three key stakeholder groups. To capture the most
evantattributes in the questionnaire thatimpactthe costperfor-
mance in projects,an extensive literature search was conducted.
A listing of the attributes that are directly or indirectly associa
with projectcostperformance was developed under seven broad
headings,as shown in Table 1.To validate the selected attributes
in an Australian context, a number of feedback sessions were
conducted among five senior industry professionals who repre
all three categories in the Australian construction industry.
The final questionnaire, consisting of 73 key attributes, was
distributed to over 160 selected professionals, targeting a goo
of construction contractors,consultants,and clients primarily in-
volved in medium- to large-scale construction projects. Of the
sible 73 attributes, 48 attributes had a sizeable correlation wit
another and were considered appropriate for further investiga
(Doloi 2008; Field 2005; Chan and Kumaraswamy 1997). The r
spondents were asked to provide their objective opinions on th
impacts of all the attributes on cost performance in one of the
or current projects on a five-point Likert scale (5 = strongly ag
4 = agree, 3 = neutral, 2 = disagree, and 1 = strongly disagre
measure the perceived agreement of the respondents’ groups
criticality of the attributes that impact project cost performanc
hypotheses were developed,as follows:
• Null hypothesis (H0): none of the groups are in agreement with
the ranking of any attribute,and
• Alternative hypothesis (H1): all three groups are in agreement
with the ranking of any attribute.
The previous hypotheses have been discussed in the contex
results and findings in the following sections. Given that there
tinues to be considerable cost overrun issues among a majorit
construction projects,the contributions made in this research are
highly relevantfor understanding the client’s,consultant’s,and
contractor’s roles in relation to achieving target cost performa
and overallprojectsuccess.
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Data Collection Process
A total of 160 questionnairesurveysweredistributed to the
selected clients, contractors, and consultants within the Australian
Construction Industry, comprising residential, commercial, and in-
dustrialbuildings.Selection of those firms and individuals from
the contractor, client, or consultant background was critical to the
success ofthis research.Given thatthe targetoutcome ofthis
research entirely relies on the representative population sample,
a simple random sampling was adopted to provide a broad spec-
trum of the three key groups in both governmentand private or-
ganizations within the industry (Akintoye 2003). The selection of
the firms/individuals had therefore been selected from industry
body websites.The contractorswereprimarily sourced from
the Master Builders of Australia (MBA) website.The consultants
were sourced from specific industry websites, which include quan-
tity surveyors from the Australian Institute of Quantity Surveyors
(AIQS) and architects from the Australian Institute of Architects
(AIA). The clients firms were identified primarily from property
development companies available from both contractors’ web
and the Australian Property Institute (API).
A totalof 94 responses were received,which consisted of 24
clients,29 consultants,and 41 contractors.The response rate of
approximately 25% of clients, 31% of consultants, and 44% of
tractors from the overallrespondents was deemed acceptable for
this study (Flyvbjerg et al.2004; Doloi 2008).Table 2 shows the
profile of the respondents in terms of their experience and the
of the projects.
As seen in Table 2,among 94 respondents across the clients,
contractors,and consultants,46% had a minimum of10 years
experiencein the construction industry.As seen in thelast
column,59% respondents were involved in projectin the range
of $75–$150 million, with 11% over $150 million. These statist
provide the basis thatthe research feedback has been based on
medium- to large-scale construction projects.
Table 1.Summary of the Literature Review Related to Project CostPerformance
Key attributes highlighted Authors
Projectrelated:Scale and scope of project,location of project,tender period and marketcondition,extentof
completion of precontract design,project organization,size of project team,type of structure,project duration,
unexpected geologicalconditions,inclementweather
Flyvbjerg etal.(2004);Chan and
Kumaraswamy (1997);Trost and
Oberlender (2003)
Contract related: Poor contract management, design changes within development period, consultation with design
team and clients in design phase, negotiations and obtaining of contracts, complexity of design and construction,
project team’s experience in development stages,contractor’s deficiencies in planning and scheduling at tender
stage,form of procurementand contractualagreements,inaccurate estimates
Akintoye (2000); Flyvbjerg etal.
(2004); Baloi and Price (2003); Doloi
(2009); Cheung etal.(2006);Green
(1989); Skitmore and Wilcock (1994)
Projectmanagementteam related:Capability of the firm’s construction team,planning and scheduling
deficiencies, buildability (including on-site prefabrication), anticipated frequency of construction variations, delays
in work approvalwaiting for information,cash flow during construction,contractor’s financial difficulties,
financing and payment of completed projects
Hicks (1992); Mansfield et al. (1994);
Chan and Kumaraswamy (1997)
Quality related:Inadequate insurance covers,mistakes and discrepancies in construction documentations,
inspection and testing of completed projects, late delivery of materials and equipments, shortage of materials and
equipmentparts,imported materials and plant parts,frequentbreakdown of construction equipment,poor site
managementand supervision,inadequate managementskills,improper control over site resource allocations,
deficiencies in cost estimates prepared,methods/techniques of construction
Iyer and Jha (2005);Cheung et al.
(2008); Tah etal.(1994); Skitmore
and Wilcock (1994);Love etal.
(2005)
Planning related:Effective monitoring and feedback process,positive attitudes of projectmanager (PM) and
project teams, effective monitoring and feedback by PM, early selection of PM with proven track record, scope and
nature of work defined in tender,understanding of responsibilities by all teams,leaderships quality of PM,
coordinating ability and rapport of PM with owners representatives, coordinating ability and report of PM with
other contractors on-site,regular budget update,staff training in the skill areas relevant to project,construction
controland status meetings
Baloiand Price (2003);Frimpong
etal.(2003);Enshassi etal.(2009);
Akintoye (2000);Mansfield et al.
(1994); Iyer and Jha (2005)
Marketrelated:Nonadherence to contractconditions,mistakes during construction,labor and management
relations,shortage of materials in current market, fraudulent practices and kickbacks,lead times for delivery of
materials, shortage of materials, price fluctuations, difficulties in obtaining materials at current price, escalation of
materialprices,availability and supplies of labor and materials
Trost and Oberlender (2003); Cheung
et al.(2006); Iyer and Jha (2005);
Chan and Kumaraswamy (1997)
Contractor related:Inadequate contractor experience,necessary variation of projects,client-initiated variations,
lack of communication between client and contractor, low speed at decision-making involving all project teams,
delay in subcontractor projects, low labor productivity, unrealistic contract duration imposed by client, shortening
of contractperiods,poor procurementprogramming of materials
Baloiand Price (2003);Frimpong
et al.(2003); Iyer and Jha (2005);
Doloi (2009)
Table 2.Summary of Respondents’ Profiles
Field of work
Respondents
(%)
Experience
(years)
Respondents
(%)
Typicalprojectbudget
(in millions of dollars)
Respondents
(%)
Clients 25 <1 2 <5 2
Consultants 31 1–5 16 5–25 8
Contractors 44 5–10 36 25–75 20
>10 46 75–150 59
>150 11
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Data Analysis and Results
The author’s research primarily utilized two separate methods to
analyze the respondents’data to identify the criticalattributes
among allthree categories thataffectcostperformance.The first
is a descriptive approach with directinterpretation of the survey
results to identify the mostcriticalattribute based on the RIW
(Frimpong etal. 2003).The RIW score is a usefulmeasure of
the relative positioning of a particular attribute perceived by the
respondents on the raw dataset(Chan and Kumaraswamy 1997).
The RIW for each attribute is calculated by summing the weights
assigned to it by each respondent. Although the RIW score does not
represent the statistically significant measurement of any instance,
the score provides a good indication on the relative meritof an
attribute based on the frequency of occurrence within the independ-
ently collected sample.
The second method, the factor analysis technique, was used to
reduce the attributes in the raw dataset into the meaningful groups
known as factors. By reducing a dataset from a group of interrelated
variables into a smaller set of factors, the factor analysis allows one
to explain the maximum amountof common variance with the
smallestnumber of explanatory concepts (Field 2005).Thus,the
factors are useful explanatory concepts for analyzing the clustered
effectson costperformance and understanding the appropriate
managementfor ensuring targetoutcomes in the projects (Iyer
and Jha 2005;Trostand Oberlender2003).In addition,linear
regression analysis based on the factor scores was performed to
investigate the collective strengths ofthe factors thatinfluence
costperformance in a project.The StatisticalPackage for Social
Sciences (SPSS) software package was used for both factor analy-
sis and regression analysis.
Descriptive Analysis
Various methods can be used to rank and subsequently identify the
relative critical attributes out of a raw data analysis. According to
numerous researchers,the mean and standard deviations are not
reliable statistics forassessing overallranking ofthe attributes.
However, RIW is one of the most widely used measures to deter-
mine the relative significance ofthe attributes (Frimpong etal.
2003).The RIW was evaluated using the following expression:
RIW ¼
P 5
i¼1ai ni
P N
j¼1xj
× 100 ð1Þ
in which xj = sum of the jth factor; j = factors 1, 2, 3, 4, : : : , N;
N = total number of attributes (48); ai is a constant that expresses
the weight given to the ith response: i ¼ 1 (very high), 2 (high), 3
(medium), 4 (low) and 5 (very low); and ni is the variable express-
ing the frequency of the ith response.
Based on Eq. (1), the RIW for all the attributes were determined
first for client, consultant, and contractor categories separately, and
then for overall samples.Table 3 shows the calculated RIWs and
rankings for 48 attributes in all four categories. The following sec-
tions discuss the significance of some of the key attributes across all
three categories with respect to the overall relative rankings shown
in the firstcolumn.
As seen in Table 3,the overallranking revealed that planning
and scheduling deficiencies is one of the most significant attributes
(RIW ¼ 2.679)that influencecost performancein projects.
Whereas both consultants and contractors share the same view-
point,clients ranked this attribute in third position.In contrast,
an effective monitoring and feedback process was perceived to
be the mostimportantfactor from the client’s perspective,which
was ranked in the third position in the overallcategory.The
third-rankedattribute,effectivemonitoringand feedbackin
overalland consultants’categories,postulatethe adequacy of
projectmanagementpractices forachieving costsuccess.Given
that the contractor’s motive is primarily driven by the earliest
pletion and site-levelmanagementof construction activities,the
monitoring and feedback process is neglected,and hence the jus-
tification for its listing at sixth position in the contractors’ cate
This is certainly the result of contractors being unaware about
roles and responsibilities in monitoring, controlling, and feedba
processes in the construction phase of the project.
Although pastresearch has reported many underlying factors
thatimpactcostperformance in projects,the revelation ofthe
impactsof planning and controlling isan importantshiftthat
has resulted from the author’s study.Whereas project planning is
a preconstruction activity in the planning phase,the bulk of the
controlling occurs in the construction phase of projects.Being a
key stakeholderin the construction phase,contractors mustbe
capable of devising an accurate time schedule such that the re
ant baseline assists in progress monitoring, reporting, and con
ling towards meeting the targets in the project. Accurate plann
requires accurate change controlprocesses to be adopted by the
contractor within the project. Thus, as far as responsibility is c
cerned, accurate planning and controlling clearly lies with the
tractors involved in the project.This finding demonstrates thata
lack of required technicalsupportand competency among the
key stakeholder(the contractors)potentially leads to failure in
delivering modern projects.
Construction methods or technique (RIW ¼ 2.656) was the s
ond most significant attribute across all three categories. Give
the complexity of modern construction projects increases acro
sectors,the requirement for the selection of appropriate constru
tion methods becomes critical for contractors. Both clients and
sultants have realized the benefits of using contemporary met
and techniques,in addition to appropriate exploitation of modern
equipmentin construction projects.
The fourth significant attribute, complexity of design and co
struction (RIW ¼ 2.586),clearly postulates the increasing com-
plexity ofdesign projectsand construction in modern projects
thatimpactcostperformance in overallprojects.The consistent
ranking ofthis attribute by clients,consultants,and contractors
attheir fifth positions asserts the underlying challenges faced
all three groups in successfuldelivery ofprojects.Whereas the
client’smotive ofvalue formoney exertssignificanttruston
consultant’s performance in most modern projects, the contra
performance is usually measured on the effectiveness ofon-site
construction with acceptable quality specification. However, a
of contractor’s in-depth understanding of the projectdesign and
specificationsoften leadsto inefficientconstruction and poor
on-site productivity in the project. This potentially triggers con
and disputes among all three parties, leading to additional cos
the project.Such conflicting requirements certainly contribute to
poorcontrolling ofcostaccounts and results in significantcost
overruns.
The fifth attribute,impropercontrolover site resources
(RIW value ¼ 2.574),clearly indicates the contractor’s inability
in handling construction resources and hence mismanagemenof
the scarce on-site resources in a project.In fact,the contractor
group has acknowledged itas a highly significantattribute by
assigning it as fourth ranking.The agreementof the level of sig-
nificance by both consultants and clients has been found at six
and seventh levels,respectively.The sixth attribute,contractors
deficiencies in realistic planning and scheduling at the tender
which has been ranked at the third position by the contractors
lights a significantconcern on contractors’prequalification and
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technical competency required to achieve successful outcomes in a
project.The contractors’ inability to clear understand the project
scope at the tender stage significantly influences their effectiveness
on resource allocation and management control, and thus affects the
costperformance in the construction stage.
Both client and consultant groups ranked the seventh attribute,
extent of completion of precontract design, at sixth and eighth rank-
ing, respectively. These rankings suggest that both client and con-
sultant groups emphasize significant completion of detailed design
at the precontractstageto minimizepotentialalternationsin
post-contract stages. However, the contractors’ raking of the s
attribute at tenth position highlights a contrast with the traditi
viewpoint that contractor’s success significantly relies on com
hensive design documentation atan early stage (Flyvbjerg etal.
2004).Although the literature review indicated a strong focus
on the comprehensive design prior to awarding of contracts,this
attribute has no significant impact on contractors’ cost manag
ability in the construction phase of a project (Enshassi et al. 20
Trostand Oberlender 2003).This finding suggests thatalthough
complete drawings and specifications, detailed investigation o
Table 3.Attributes That Influence CostPerformance
ID Attributes
Overall Clients Consultants Contractors
RIW
(%) Ranking
RIW
(%) Ranking
RIW
(%) Ranking
RIW
(%) Ranking
C19 Planning and scheduling deficiencies 2.679 1 2.549 3 2.652 1 2.780 1
C15 Methods/techniques of construction 2.656 2 2.594 2 2.615 2 2.725 2
C44 Effective monitoring and feedback process 2.632 3 2.660 1 2.596 3 2.642 6
C14 Complexity of design and construction 2.586 4 2.505 5 2.559 5 2.656 5
C36 Improper control over site resource allocations 2.574 5 2.461 7 2.540 6 2.670 4
C10 Contractor’s deficiencies in planning and scheduling at
tender stage
2.504 6 2.549 4 2.485 7 2.684 3
C4 Extentof completion of precontractdesign 2.499 7 2.461 6 2.466 8 2.546 10
C28 Escalation of materialprices 2.458 8 2.350 9 2.392 10 2.574 9
C31 Mistakes and discrepancies in construction documentations2.429 9 2.394 8 2.411 9 2.615 7
C38 Client-initiated variations 2.429 10 2.239 18 2.336 12 2.422 14
C48 Staff training in the skillareas relevantto project 2.405 11 2.350 10 2.336 13 2.491 11
C22 Cash flow during construction 2.388 12 2.328 12 2.318 14 2.477 12
C11 Design changes within development period 2.301 13 2.017 27 2.151 21 2.587 8
C21 Delays in work approval waiting for information 2.266 14 2.217 19 2.207 18 2.340 17
C3 Tender period and marketcondition 2.236 15 1.884 35 2.299 15 2.078 26
C39 Lack of communication between clientand contractor 2.236 16 2.283 16 2.225 17 2.078 28
C29 Unexpected geological conditions 2.155 17 2.305 14 2.244 16 2.064 29
C30 Inclementweather 2.143 18 1.906 33 2.207 19 2.216 22
C35 Poor site managementand supervision 2.143 19 1.884 37 2.095 24 2.340 18
C7 Form of procurementand contractual arrangements 2.120 20 2.328 11 2.559 4 1.72 41
C9 Poor contractmanagement 2.114 21 2.128 21 1.891 30 2.147 25
C37 Inadequate contractors experience 2.108 22 1.796 42 2.040 26 2.353 16
C1 Scale and scope of project 2.073 23 1.906 31 2.058 25 2.188 24
C41 Delay in subcontractor’s projects 2.050 24 2.039 26 2.373 11 1.885 36
C42 Lower labor productivity 2.050 25 2.106 24 2.132 22 1.954 33
C33 Labor and managementrelations 2.038 26 1.840 40 1.873 32 2.285 19
C20 Buildability (including on-site prefabrication) 2.027 27 1.884 36 1.836 35 2.257 20
C40 Low speed atdecision-making,involving allprojectteams 2.027 28 2.039 25 2.021 28 2.023 30
C26 Frequentbreakdown of construction equipments 2.015 29 1.530 46 1.854 33 2.436 13
C16 Availability and supplies of labor and materials 1.992 30 2.283 15 1.502 47 2.216 21
C13 Type of structure 1.945 31 2.106 23 1.724 43 2.009 31
C5 Projectteam’s experience in development stages 1.939 32 2.305 13 1.743 42 2.078 27
C12 Lack of communication between design team and clients
in design phase
1.939 33 2.172 20 1.891 31 1.858 37
C27 Lead times for delivery of materials 1.928 34 1.906 32 2.188 20 2.395 15
C43 Poor procurementprogramming of materials 1.904 35 1.862 39 1.799 39 1.885 35
C32 Nonadherence to contract conditions 1.893 36 1.751 43 1.762 41 2.009 32
C34 Fraudulentpractices and kickbacks 1.870 37 1.330 48 1.854 34 2.216 23
C2 Location of project 1.817 38 1.884 34 1.799 36 1.789 39
C45 Understanding of responsibilities by all teams 1.817 39 2.128 22 1.520 46 1.844 38
C17 Capability of the firm’s construction team 1.776 40 1.951 28 1.799 37 1.652 42
C8 Deficiencies in cost estimates prepared 1.747 41 2.239 17 1.687 44 1.486 43
C6 Size of projectteam 1.736 42 1.463 47 1.762 40 1.885 34
C18 Projectduration 1.689 43 1.951 29 2.021 27 1.280 44
C25 Inspection and testing of completed works 1.689 44 1.663 44 1.613 45 1.762 40
C47 Coordinating ability and rapportof PM with other
contractors on-site
1.625 45 1.929 30 1.947 29 1.197 45
C46 Coordinating ability and rapportof PM with owner’s
representatives
1.578 46 1.818 41 2.114 23 1.032 47
C24 Financing and payment of completed projects 1.462 47 1.596 45 1.799 38 1.129 46
C23 Contractor’s financial difficulties 1.310 48 1.862 38 1.409 48 0.895 48
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dynamics,and a thorough understanding ofthe client’s require-
ments of the projectatthe precontractdesign stage are some of
the importantconsiderations,these attributes are notnecessarily
highly significantin terms of reducing costoverruns atthe latter
stages of projects.
The eighth attribute,escalation ofmaterialprices(RIW ¼
2.458), was equally important for both client and contractor groups
at their ninth positions, which is also supported by the findings of
Akintoye (2000). However, consultant’s perceived ranking at tenth
position in this attribute shows the resilience for not being respon-
sible for achieving overall cost performance in projects. Similarly,
the attribute mistakes and discrepancies in construction documen-
tation atthe ninth ranking (RIW ¼ 2.429)significantly impacts
contractor’s cost performance, at their seventh position in the list.
Both clients and consultants are nevertheless in agreement at their
eighth and ninth positions,respectively.
Among the middle orderattributes,client-initiated variations
scored tenth position in the overall ranking. This finding is similar
to the findings ofFlyvbjerg etal. (2004)and Mansfield etal.
(1994).Although thetwelfth and fourteenth rankingsof the
client-initiated variation attribute by both consultants and contrac-
tors show a reasonable agreement with the overall ranking, client’s
eighteenth ranking does notsupportthis as a perceived issue for
managing project cost performance. The requirement for appropri-
ate stafftraining fordeveloping relevantskills required in the
project and adequate cash flow during construction secured consis-
tentranks among allthree stakeholder groups.Although design
changes within the project development period has been perceived
to be relatively less important by client and consultant groups, the
impactof this attribute was perceived to be relatively highly sig-
nificantfor contractors (RIW ¼ 2.587 and eighth ranking)with
an overallranking at thirteenth position.
Among the lowestorder attributes,contactors’ financialdiffi-
culty was the least significant among both consultant and contractor
groups, with a relatively higher weight by the client group. Although
the material-related attribute wasasserted to be highly critical
for impacting time and cost delays in past research (Frimpong et al.
2003; Enshassi et al. 2009), an equivalent attribute, lead times for
delivery of material, was found in the author’s research to be quite
significant(overallrankingof 34, RIW ¼ 1.928).Similarly,
revelation of some of the key lower order attributes (procurement
programming ofmaterials,understanding ofresponsibilitiesby
all teams,projectlocation,projectlocation,size of project
team, and deficiencies in cost estimates) set a clear contrast to the
assertions made by pastresearchers in the field (Akintoye 2000;
Frimpong et al. 2003; Enshassi et al. 2009).
Test of Commonality among the Respondents
To validate the degree of agreements between all three respondents’
groups with respectto the attribute ranking,Kendell’s coefficient
of concordance (W) was relevant for this study. This coefficient is
expressed as follows:
W ¼12U − 3k2nðn − 1Þ2
k2nðn − 1Þ ð2Þ
in which
U ¼Xn
j¼1
R2
j ð3Þ
and
Rj ¼Xk
i¼1
Rij ð4Þ
in which n = number of attributes; and k = number of groups
sample. The value of W ranges between 0 and 1, with 1 corres
ing to a perfectmeasure oftotalagreementand 0 indicating
no agreementwithin the observed groups (Grzegorzewski2006).
Employing Eqs.(2)–4 on the collected sample,Kendell’s coeffi-
cient was 0.9068, which shows a significant agreement on the
among allthree respondents’ groups.
Although the resultof Kendell’s coefficientof concordance
depicts a considerable agreementon the ranking among allthree
groups, attributable to the large number of attributes (e.g., n ¼
further testing for validation is recommended.Thus,Eq. (5) was
adopted to employ the chi-square approximation of the sampl
distribution of W,as follows:
χ2 ¼ kðn − 1ÞW ð5Þ
Based on the Eq.(5),the calculated value of χ2 was 127.86.
Using the criticaltable forχ2 for n ¼ 48,degree offreedom
ðn − 1Þ ¼ 47,and significance α ¼ 0.05,the value ofχ2 was
calculated as follows:
χ2ðn−1Þ
0.05 ¼ χ2ð47Þ
0.05 ¼ 63.996
Given that the calculated value of χ2 was greater than the critical
value of χ
2ðn−1Þ
0.05 , the null hypothesis (H0) as stated previously could
notbe accepted.However,the results supportthe alternative hy-
pothesis (H1) thatclients,consultants,and contractors are allin
agreement with respect to how they rank the attributes. Fig. 1
the profiles of the top ten attributes as considered by the clien
consultants,and contractors.Although the scale of the perceived
importance is relatively differentwith some degree ofdiversity,
the overall trend shows a high degree of agreement among al
groups of respondents.
Factor Analysis
Although relative importance weights provide some meaningfu
terpretation on the respondents’ perceptions, such measures
quite convincing as an objective outcome for managing projec
overruns. Factor analysis is appropriate to determine the mult
ate relationships and the mostcriticalfactors among the entire
attributes across all three categories (Doloi 2008). Although nu
ous researchers have adopted factor analysis on similar attribu
in various contexts,generic factors thatimpactcostperformance
in the contexts ofclient,consultant,and contractorperceptions
and underlyingmanagementresponsibilitiesremainunknown
2
2.1
2.2
2.3
2.4
2.5
2.6
2.7
2.8
2.9
C19 C15 C44 C14 C36 C10 C4 C28 C31 C38
Attributes
RIW (%)
Overall Clients Consultants Contractors
Fig. 1. Profiles of top ten attributes as considered by clients, cons
tants,and contractors
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(Akintoye 2000).Thus,in this research,the resultfrom an con-
firmatory factoranalysis establishes a benchmark on the cluster
of attributes into severalcriticalfactors thatimpartclearunder-
standing of the underlying impacts on cost performance and their
effective managementacross the industry.
As a first step to performing the factor analysis,the adequacy
of the survey data was examined by conducting the Kaiser-Meyer-
Olkin (KMO) testand the Bartlett’stestof specificity (Zhang
2005).The KMO represents the ratio of the squared correlation
between variables to the squared partial correlation between vari-
ables. The KMO statistics vary between 0 and 1. A value close to 1
indicates thatpatterns of correlations are relatively compact,and
consequently factor analysis should yield distinct and reliable fac-
tors. A recommended bare minimum value of KMO for a satisfac-
tory factoranalysisis greaterthan 0.50 (Field 2005).In this
analysis, of the possible 48 attributes, a total of 36 had a sizeable
correlation (correlations coefficients ranging from 0.6781–0.8752)
with one another,with a KMO value of 0.793.The remaining 12
attributes had insignificantrelationships with any other attributes
and were thus excluded in the factoranalysis.To testthe null
hypothesis that the correlation matrix is an identical matrix,prin-
cipal component analysis requires the probability associated with
Bartlett’s test of sphericity to be less than the level of significance
(Zhang 2005). The Bartlett’s test of sphericity was 986.456 with an
associated probability of 0.0000 (less than 0.001),which satisfies
this requirement. The details of factor analysis are well documented
in the literature, including Field (2005) and Doloi (2008). They are
therefore notdiscussed in this manuscript.
Principal components analysis was adopted to reduce the highly
correlated project attributes into a smaller number of key factors of
the overall cost overrun issues. As previously noted, principal com-
ponent analysis was performed on the selected 36 attributes and a
total of eight factors were extracted with eigenvalues greater than 1.
Table 4 depicts these eight components (factors) that cumulatively
explain a total of 85.4% of the variance, and the other components,
which accounted for a total less than 14.6%, were dropped. Each of
the attributes had higher weights towards one factor, with a loading
greaterthan 0.6.However,loadings ofthe two attributes under
factors 6 and 8 were slightly below 0.6 but above 0.55.The reli-
ability of the attributes under all the eight factors was evaluated by
determining Cronbach alpha (α) values (Field 2005).The overall
Cronbach alpha value was 0.863,which is above the acceptable
limit of 0.70 for a satisfactory level of reliability in the given data-
set. In addition, the Cronbach alpha values for the attributes under
each factorin Table 4 were determined,and are presented in
Table 5.Based on the cluster of the attributes under each factor,
the representative names of the factors were assigned,depicting
the nature ofthe underlying issues associated with costperfor-
mancein projects.An interpretation ofthesefactorsis pre-
sented next.
Regression Analysis
Although factor analysis allows one to group the major attributes
into meaningfulfactors,the degree of impacts of these factors in
relation to predicting costperformance remains obscure (Doloi
2009).In this section,the multivariate regression technique was
applied to investigate the relationship between the factorsand
the success of achieving costperformance.
In a regression model,the dependentvariablesare a linear
combination of the independent or explanatory variables.The in-
dependentvariablesare the attributes,which contribute to the
costoverruns,and the dependentvariable is the resulting cost
performance (Y1). In this research, the factor scores, derived from
the eight factors listed in Table 4, were entered into the regre
model as categorical variables for quantifying the impacts acc
ing to the following equation (Field 2005):
Yi ¼ β0 þ β1x1i þ β2x2i þ β3x3iþ · · · þβj xji þ εi
in which Y is the value of dependent variables (cost performan
β0 is a constantand the interceptatthe y-axis;β1 through βj =
estimated regression coefficients;x1 through xj are the values of
the independentor predictor variables;εi is an error term,which
is a random variable with a mean of 0; i = index of the perform
variable being predicted;and k = number of independentor pre-
dictor variables.
Table 6 shows the results of the final regression model of th
factors (1, 3, 5, 2 and 4). The number of explanatory factors in
regression analysis must be diminished to minimize the impac
weak predictive models (Doloi 2009; Ling et al. 2004). Given t
the factors are derived using orthogonalrotation in Table 4,the
estimated standard errors are essentially equal for all regressi
iables.The parameter estimates of regression coefficients for a
five factors (1, 3, 5, 2 and 4) are significant at p < 5%. The go
ness of fit for the model was measured by the coefficient of de
mination R2 and the adjusted coefficientof determination R2,
which were used to select the reduced models. The value of R2 will
change rapidly with the addition of new attributes into the mo
whereas R2 takes the generalization capability of the modelinto
consideration. R2 and R2 should be very close to accept the model
(Field 2005), and thus the following reduced model is acceptab
The finding of the regression analysis clearly supports the argu
that the bulk of control of cost overrun depends on the contrac
ability in efficientplanning,monitoring,and site managementin
projects.Although consultants’ and clients’ responsibilities lie in
providing efficientdesign overthe planning and design stages,
the client plays a significant role in providing effective commu
cation protocol in the project. These findings validate the relev
and strengths of the factors in terms of their collective influen
projectcostperformance.
Cost performance ¼ 0.786 þ 0.307 ðaccurate project planni
and monitoringÞþ 0.266 ðeffective site managementÞþ 0.231
ðcontractors’efficiencyÞþ 0.146 ðdesign efficiencyÞþ 0.094
ðcommunicationÞ.
Discussion of Critical Factors
Table 4 shows eightcriticalfactors extracted from a totalof 36
selected attributes based on the responses received from clien
consultants and contractors in the overall sample.The factors are
(1) accurate project planning and monitoring, (2) design efficie
(3) effective site management, (4) communication, (5) contact
efficiency,(6) projectcharacteristics,(7) due diligence,and
(8) marketcompetition.
The first factor,accurateprojectplanning and monitoring,
which explains a total variance of 23.9%, significantly emphas
the technicalcompetency ofthe projectteam in terms ofclear
understanding ofthe projectscope,developmentof appropriate
statementof work,realistic estimation ofactivity duration,and
baseline planning for controlling and monitoring over the exec
stage of the project. Selection of contemporary methods and t
niques thatcommensurate the complexity of on-site constructio
activities is of utmostimportance in managing projectcostover-
runs. The project manager’s efficiency in monitoring and contr
ling the baselineprojectdependson effectivereporting and
feedback processes. This finding depicts a clear shift of empha
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of some of the criticalfactors revealed by pastresearch,such as
projectcomplexity(Akintoye2000), incrementof material
prices (Enshassietal. 2009),and contractor’s financialdifficulty
(Frimpong et al. 2003). However, this finding supports the ass
that large cost overruns are typically seen as signs of inefficie
most public sector projects (Flyvbjerg et al. 2004). Supporting
findings reported in the Descriptive Analysis section, the first f
being project planning and monitoring clearly highlights the co
tractor’s roles and responsibilities of in the project.
The second factor,design efficiency,with a totalvariance of
15.4%,encompasses the significance of the extent of completio
Table 4.Overall Rotated Factor Loadings
Factors/attributes
Factor loading Variance
explained
(%)1 2 3 4 5 6 7 8
Factor 1: accurate projectplanning and monitoring 23.9
C19.Planning and scheduling deficiencies 0.859
C15.Methods/techniques of construction 0.784
C14.Complexity of design and construction 0.73
C10.Contractor’s deficiencies in planning and scheduling at tender stage0.721
C44.Effective monitoring and feedback process 0.698
Factor 2: design efficiency 15.4
C4. Extentof completion of precontractdesign 0.876
C31.Mistakes and discrepancies in construction documentations 0.807
C38.Client-initiated variations 0.798
C11.Design changes within development period 0.719
C20.Buildability (including on-site prefabrication) 0.701
Factor 3: effective site management 10.8
C36.Improper control over site resource allocations 0.828
C28.Escalation of materialprices 0.842
C22.Cash flow during construction 0.797
C42.Lower labor productivity 0.708
C21.Delays in work approvalwaiting for information 0.689
Factor 4: communication 9.2
C39.Lack of communication between clientand contractor 0.788
C35.Poor site managementand supervision 0.776
C9. Poor contract management 0.764
C12.Lack of communication between design team and clients in design phase 0.718
Factor 5: contractor’s efficiency 7.6
C37.Inadequate contractor’s experience 0.873
C40.Low speed atdecision-making,involving all projectteams 0.759
C5. Projectteam’s experience in development stages 0.743
C8. Deficiencies in cost estimates prepared 0.688
C23.Contractor’s financialdifficulties 0.675
Factor 6: projectcharacteristics 7.3
C1. Scale and scope of project 0.796
C13.Type of structure 0.694
C2. Location of project 0.648
C29.Unexpected geologicalconditions 0.598
Factor 7: due diligence 6.9
C45.Understanding responsibilities by all teams 0.877
C33.Labor and managementrelations 0.782
C32.Nonadherence to contractconditions 0.689
Factor 8: marketcompetition 4.3
C8. Tender period and marketcondition 0.806
C43.Poor procurementprogramming of materials 0.717
C27.Lead times for delivery of materials 0.638
C41.Delay in subcontractor’s work 0.573
Total variance explained (%)85.4
Table 5.Reliability Analysis
Attributes Cronbach’s alpha (Cα)
All attributes in Table 3 0.863
Attributes in factor 1 0.904
Attributes in factor 2 0.879
Attributes in factor 3 0.911
Attributes in factor 4 0.946
Attributes in factor 5 0.898
Attributes in factor 6 0.879
Attributes in factor 7 0.863
Attributes in factor 8 0.882
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of precontractdesign,mistakes,and discrepanciesin design
documentation,clientinitiated variations,design changes,and
buildability issues in the construction phase of the project. Clarity
of the design at the pretender stage allows contractors to realisti-
cally estimate the costs of construction and hence possibilities for
less variation in subsequent project phases. Mistakes and discrep-
ancy in design documentation naturally trigger the variations and
hence are a major source of cost increases for both clients and con-
tractors (Akinciand Fischer1998).The significance ofclient-
initiated variations,design changes,and complexity in on-site
construction overcostoverrun has been supported by research
(Akintoye 2000;Iyer and Jha 2005).Given thatthe consultants’
competence in design efficiency also depends on clients’ consistent
inputs (e.g.,client-initiated variations) on design selection,effec-
tive managementof this factor clearly relies on the jointrespon-
sibility of both clientsand consultantsin the project.The
consultants’ ability t understand the client’s expectations and pro-
vide a clear design at the pretender stage plays a significant role in
achieving efficientdesign outcomes.
The third factor, termed effective site management, with a total
variance of 10.8%, refers to the influence of site-level management
issues over cost overrun (resource utilization, material pricing, cash
flow, labor productivity, and delays in decision-making). Appropri-
ate allocation of resources and their optimized utilizations by the
on-site contractorare perceived to have significantinfluence on
construction cost.Controlof materialprice escalation depends
on effective management of a procurement schedule and provision
for relevantcontractualarrangements among the suppliers.Con-
tractors’ financial position and their ability to maintain a seamless
cash flow during the construction phase have significant influence
on on-site costperformance.Both poorlaborproductivity and
delay in the approval process are the key reasons for construction
delay, leading to overall cost overrun in projects (Doloi 2009). This
finding supports the generally accepted view that poor management
controlsignificantly impacts the contractor’s ability to overcome
the unforeseeable challenges in site-related construction activities
and results in additional costs to the project budget (Akintoye 2000;
Akinci and Fischer 1998; Mansfield et al. 1994). Through proactive
planning and good development of management competencies, the
contractor is generally the appropriate party for providing effective
site managementpractices on-site.However,given thatproactive
decision approvalby the clients significantly empowers the con-
tractor’s management ability, the overall site is well managed with
a shared responsibility between both parties.
The fourth factor, communication, with a total variance of 9.2%,
was significantin terms of transparency and clarity of communi-
cations between all parties and enabling seamless coordination and
integration forperforming theirroles and responsibilities in the
project.Lack of communication between clients and contractors
over the construction phase and between clients and the designer
over the design phase can easily hinder the contractor’s capac
keep on the construction schedule and meet the target constr
Thus,establishment of an appropriate communication protocol
the responsibility of all three parties in the project. Similarly, p
supervisory supportand inadequate contractmanagementamong
the subcontractors can potentially lead to disputes and conflic
affectconstruction activities on-site.Although the importance of
effective communication was one of the underlying factors am
clients,contractors,and consultants,the significance of the four
underlying attributes has been revealed by past research (Che
et al. 2008; Frimpong et al. 2003). Being one of the key stakeh
ers,the clientplays a significantrole in maintaining an effective
communication protocolwithin the project.The client’s respon-
sibility in effective communication and its influence in achievin
successfulprojectoutcomeshavealso been reported in past
research (Doloiet al. 2011;Cheung etal. 2006;Bresnen and
Marshall2000).
The fifth factor,contractor’s efficiency,which explains a total
variation of7.6%,has traditionally been perceived asone of
the leastimportantconsiderations thatimpactcostperformance
in projects.Although contractor efficiency was revealed to be an
important factor in the contractor preselection process in the t
phase,a lack of relevantexpertise on the partof the contractor,
technicalcompetency in costestimation,capacity forspeedy
decision-making,and sound cash flow position were some of the
key attributes thatcontributed to the contractor’s inefficiency in
achieving costsuccessin projects.Althoughmaintainingan
efficient work standard is a contractor’s responsibility over the con-
struction phase, the responsibility for selecting the right contr
lies with the clientin mostprojects.
The sixth factor,associated with project characteristics,with a
totalvariance of 7.3%,was only marginally significantover cost
overrun, as perceived by all three respondent groups. Past res
has revealed thatcostoverrun is directly related to projectscale
and complexity (Akintoye 2000; Frimpong et al. 2003). Howev
the findings of the author’s research lead to the conclusion tha
these two attributes do not necessarily directly contribute to p
cost performance. In contrast, management of larger project s
and complexities can be considered as the subsets of the tech
competency ofthe projectteam,which can easily be addressed
through factors such as accurate project planning and monitor
effective site management, and communications. Although the
of the responsibilities associated with management of this fac
with thecontractors,both clientsand consultantsare equally
responsible for maintaining effective communication protocols
the project.
The factor due diligence, comprising three underlying attrib
was criticaland atthe seventh position,with a totalvariance of
6.9%. Precise understanding of the responsibilities and contra
obligations by allteams in a projectsignificantly contributes to
Table 6.Results of Multivariate Regression Analysis
Variable β coefficient Standard error t-value Significance (p) R2=adjusted R2
Costperformance
Constant 0.786 0.0113 2.420 0.0001 0.668=0.576
Factor 1 (accurate projectplanning
and monitoring)
0.307 0.0116 2.623 0.0003 F ¼ 7.299
Factor 3 (effective site management) 0.266 0.0116 1.674 0.0122 p ¼ 0.0001
Factor 5 (contractor’s efficiency) 0.231 0.0116 1.306 0.0235 Dublin-Watson ¼ 1.987
Factor 2 (design efficiency) 0.146 0.0116 1.569 0.0370
Factor 4 (communication) 0.094 0.0116 1.476 0.0423
Note:Variables are significant atp < 0.05.
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reducing conflicts and disputes and hence successfully meeting
the target.Similarly,a positive relationship between laborers and
management is highly significant for promoting a conducive work-
ing environment,which potentially contributes toward high pro-
ductivity in projects.The link between construction productivity
and cost performance has been reported in numerous research re-
ports, including Doloi (2009) and Chan and Kumarswamy (1997).
The eighth factor, termed market condition, with a total variance
of only 4.3%, revealed that competition in the marketplace is com-
paratively a weaker determinant with respect to project cost perfor-
mance. With appropriate planning and programming in projects, all
the underlying attributes associated with marketconditions can
easily be controlled proactively. Shortage of materials and lead time
for delivery should not be seen as the primary causes for delay in a
subcontractor’s work. In contrast, these attributes are the result of
poor procurementplanning and weaker controlin executing pro-
curement schedule in most projects. The extent of the tender period
and tender conditions in the marketplace are not determinants of the
contactor’s inability to controlcosts on-site.Avoidance of over-
commitments and effective management of resources are somewhat
closely related to contractor’s competence and thus both of these
attributes are criticalfor managing costs in projects (Akinciand
Fischer 1996; Hicks 1992; Akintoye 2000; Mansfield et al. 1994).
This finding shows a clear contrast between the past understanding
of the marketdynamism being an independentphenomenon
(Akintoye 2000; Bowen and Edwards 1998) and the management
opportunity of the fluctuating marketconditions with contractors
being proactive in the projectdevelopmentenvironment.
Conclusions and Further Research
Focusing on the three majorindustry groups (consultant,client,
and contractor),this research investigated the criticalfactors that
affectcost performanceacrossboth the preconstructionand
construction phasesof projects.Based on descriptive analysis,
48 selected attributes associated with project cost performance were
ranked using the relative performance index as perceived by clients,
consultants,and contractors in Australian construction projects.
By performing confirmatory factoranalysis,36 attributes ofthe
48 selected attributes were furtherreduced to eightkey factors
for an investigation of their quantitative impacts on projectcost
performance.The influence ofthese eightkey factorson cost
performance was further validated using regression analysis. Based
on multivariate regression analysis,five of the eightkey factors
were further highlighted as highly significant. The five significant
factors were accurate projectplanning and monitoring,effective
site management,contractors’efficiency,design efficiency,and
communication.The roles and responsibilitiesof the clients,
consultants,and contractors were then analyzed in relation to the
factors for devising appropriate management strategies and reduc-
ing project costoverruns.
One of the key findings, that project planning and control mea-
sures play a significantrole in overallprojectcostperformance,
shows a clear shift of the industry-wide perception of cost perfor-
mance being heavily reliant on the competency of contracting par-
ties alone. The emphasis on the technical planning and controlling
skills of the contracting parties for effective managementof cost
performance clearly adds a new dimension to the currentbody
of knowledge in the field,in which the contractor’s performance
in terms of financial strengths,relevant experience, firm size,and
so on was reported to be closely linked with achieving cost targets
in mostprojects (Iyerand Jha 2005;Chan and Kumaraswamy
1997).Although Iyer and Jha (2005) asserted the importance of
contractors and consultants in the cost controlling and monito
process,the author’sresearch furtherhighlighted the potential
influence of both parties in the technicalplanning of the project.
Implementingappropriateconstructionmethodsand effective
reporting and monitoring procedures among the projectparties,
a common standard can be established for managing on-site c
struction projects,which potentially reduces numerous mistakes
and errors in the downstream construction phase.Programming
and sequencing of work during the on-site construction stages
be regularly updated and forecasted to limit changes of delays
subsequent cost overruns throughout the project. Design effic
in terms of extentand clarity of precontractdesign atthe initial
stage of projectcreation is highly necessary to produce realistic
project time and cost plans. Failure to provide a complete deta
scope and design forthe projectwill resultin discrepancies in
contract documentation and the likelihood of mistakes during
struction.The shift of emphasis to the previously noted technica
issues in achieving costperformance in Australian construction
projects is clearly a key contribution to new knowledge in the
rent construction engineering and management literature.
The contractor’s ability in effective site management is a vi
requirement for controlling project costs. An experienced cont
tor with a sound workforce and cash flow during construction
can provide a significant expertise to better control the projec
finding issimilarto the assertionsin Frimpong etal. (2003).
Coordination between allprojectparticipants is one of the most
important factors to achieve successful project outcomes. Com
nication and personal rapport between all project participants
lead to a reduction in unnecessary paper work and therefore g
reduce the time and overallproject costs.
The contractor’s inefficiency in terms of relevant project exp
rience and costestimation process potentially affects the overall
projectcostperformance.Furthermore,the contractor’s financial
hardships and hence delays in the subcontractor’s payments c
possibility affect overall financial control. The contractor’s lead
ship skills and ability to coordinate numerous activities on-site
a significant impact on project cost performance.A good upfront
understanding of the contractors on the project design and on
constructability issuespotentially enhancesthe probability of
achieving positive projectcostperformance.The revelation that
the scale, scope, and structure of the project are less likely to
projectcostperformance is in contradiction with the findings of
some pastresearch,including Akintoye (2000),Frimpong etal.
(2003),and Flyvbjerg etal. (2004).
Based on thereliability ofthe datasetand robustnessof
the analysismethodology,the author’sresearch revealed some
degree of clear contraston the mostsignificantfactors from pre-
viously published research, and provides an opportunity for un
standing the perceived shiftof industry practices in construction
projects. Although factors such as project size, type, and comp
ity (Akintoye 2000;Baloi and Price 2003),financialdifficulty
(Frimpong etal. 2003),inaccurate costestimation (Akinciand
Fischer 1998),contractualarrangements (Mansfield etal. 1994),
and length of construction (Flyvbjerg et al. 2004) have signific
effects on costperformance in mostprojects,the findings of this
research highlighta new emphasis on well-developed technical
skills as the key in controlling costoverruns in modern projects.
This is perhaps attributable to the shiftin the contractor’s roles
and responsibilitiesassociatedwith the ever-increasingnon-
traditionalprocurementroutesselected in projects.Given that
the contractors are engaged with stringent contractual terms,they
are increasingly responsible fortheirown profitsor lossesin
modern projects. Thus, the lack of the contactor’s ability in ac
planning and efficient control process is one of the most signifi
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Table 7.PotentialChecklists for Addressing Cost Overruns in Projects
Factors
Checklist
Clients Consultants Contractors
Accurate project
planning and
monitoring
Clear scope definition Appropriate requirementanalysis Clear understanding of the projectscope
Clear quality specifications Simplification of the design complexityUnderstanding the design
Establishmentof a clear change
request and feedback protocol
Consideration of buildability and requirements
of specialized resources
Construction methods and techniques
Avoid change of scope and
variations
Establishmentof a clear change request
and feedback protocols
Details of resources required
Agreementon appropriate project
budget and delivery timeframe
Accurate work flow planning
Developmentof accurate schedule
Clear process of projectcontrol
Clear change requestprotocol
Monitoring and status reporting protocols
Design efficiencyEarly engagement of consultants for
developmentof precontract design
Detailed and error-free design Assessment of design,buildability,
and resource requirements
Accurate construction documentationDesign simplification Accurate construction planning
Buildability analysis Agreed communication and feedback
protocols
Rigorous liaising with clients and
design updates
Accurate projectdocumentation
Effective site
management
Clear contract documentation and
administration
Error free design Clear construction documentations
On-time approvaland invoice paymentsEfficientdesign supervision Proper controlover site resource allocation
Nondisruptive cash flow Clear projectdocumentation Efficientsite managementand supervision
Appropriate mechanisms for early price
lock-in for construction materials
Clear projectand quality specifications Efficientmonitoring of labor productivity
Nonconformance compliance protocolsEfficientprogress reporting protocol
Nondisruptive cash flow
Accurate risk managementplan and
controlling process
CommunicationEstablishmentof a clear communication
protocol
Establishmentof a clear communication
protocol
Establishmentof a clear communication
protocol
Effective use communication mediaEffective use communication media Efficientsite managementand supervision
Participation in regular site meetings Proper controlover subcontractors and
effective contract administration
Contractor’s
efficiency
Accurate understanding of technical
issues associated with the project
Efficient decision-making and communicationRelevantexperience and availability of
technical expertise
Selection of contractors with relevant
technicalexpertise
Accurate understanding of technical
issues associated with the project
Accurate estimation by exhausting
appropriate tools,techniques,and processes
Efficientdecision-making and
communication
Frequent communications with client
and contractors on design-related issues
Efficientdecision-making and
communication
Availability of funds
Project
characteristics
Size and complexity of the project Projectdesign and structures Accurate site assessment
Selection of projectlocation Clear assessmentof the geological
conditions
Accurate understanding of design and
specifications
Assessmentof site accessibility and
sharing appropriate resistibility
Clear understanding of site,accessibility,
and buildability issues
Accurate assessmentof site accessibility,
managementof site-related risks,and safety
issues
Due diligence Exercise responsibility Exercise responsibility Understanding of the localauthorities and
regulations
Appropriate and clear contractual
agreements with allparties
Follow contractualagreements Conducive labor relations
Follow contractualagreements
Market
competition
Acquire relevant knowledge on the market
conditions
Selection of appropriate design Carefulassessmentof marking conditions
and competitions
Appropriate tender process Use of materials based on market conditions,
including supply and demand analysis
Carefulprocurementplanning
Selection of appropriate procurement
routes
Integration of lead time in procurement
planning
Carefulselection of subcontractors
Early engagementof subcontractors and
efficientcontract administration
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factorsin medium-to large-scale(ranging from $75 million
to over $150 million) Australian construction projects.Although
the author’s research has highlighted the key factors thataffect
construction costperformance based on the data collected in an
Australian context, the results provide a solid basis for comparing
or contrasting past findings in a global perspective (Akintoye 2000;
Baloi and Price 2003; Enshassi et al. 2009; Mansfield et al. 1994).
Given that there has been a clear shift in emphasis of the underlying
responsibilities of the key stakeholders in terms of effective man-
agementof the criticalfactors,irrespective of geographicalloca-
tion, the currentindustry practiceconcerning achievementof
cost performance needs careful consideration in projects globally.
Table 7 depicts a potential checklist for addressing the cost over-
runs in projects. Although the checklist is predominately developed
by summarizing the attributes under the eight key factors reported
in Table 3, the extent of its usability may significantly differ based
on factorssuch asprojecttypeand size,culturalsensitivity,
geographicalboundaries,and so on.Nevertheless,this checklist
should herald a meaningful insight for addressing the chronic issue
of projectcostoverruns among professionals in the construction
industry.
The author’s findings have some limitations.Although the re-
sults of the multivariate regression analysis depict the influence of
five key factors on cost performance, the lack of a new dataset on
independent variables renders the prediction model quite incompre-
hensive and impractical.However,it has been recommended that
furtherinvestigation in termsof developing predictive models
should be undertaken to validate the similar shift in industry prac-
tices across varied sizes and types of projects at different locations.
To this extent, nonlinear regression analysis based on independent
collection ofindustry data on the factors should be performed
to develop the prediction modeland enhance the relevantbody
of knowledge furtherwithin the construction engineering and
managementdomain.
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