Construction Delays Causing Risks on Time and Costa Critical Review

There is an increase in the number of construction projects experiencing extensive delays leading to exceeding the initial time and cost budget. This paper reviews 41 studies around the world which has surveyed the delay factors and classified them into Groups. The main purpose of this paper is to review research which has categorized the causes responsible for time delays and cost overruns in projects. The intention was to see whether these causes are valid for projects being executed in Sabah East Malaysia allowing a mitigation plan to be prepared. The collected list has 113 causes for delays which were categorized into 18 different groups. Most of the research has analysed the responses from Questionnaire surveys. The collected data are used to rank the problem factors. The data are further used to investigate and analyse the reported “Importance Index, Frequency Index, Severity Index, Relative Importance Index, Relative Importance Weight, Weighted Average, Mean, Standard Deviation and Variance”. The collective comparison has revealed that the ranking given by all the researchers is not the same. Further each and every study has different rank ratings from different group. This review paper attempts to provide an updated compilation of the earlier studies on ranking of the delay causers, which are never similar and constant for universal projects. From the critical review, it is concluded that this type of research requires a different method or approach to generate meaningful answers and that there is a strong case against opinion surveys.


Introduction
The purpose of this study is to critically review and identify the applicability of past studies on determining the factors causing time delays and cost overrun in current projects.This goal has been accomplished by reviewing articles published during the last 15 years (since 1995) in various project management journals like: International Journal of Project Management (IJPM), Journal of Construction Management Economics (JCME), Journal of Management in Engineering (JME), Engineering Construction and Architectural Management Journal (ECAMJ) and others.
The biggest customer of the construction industry in most countries is the government (Okpala and Aiekwu, 1988).To the dislike of owners, contractors and consultants, many government projects experience extensive delays and thereby exceed the initial time and cost estimates (Odeh and Bataineh, 2002).This problem is more evident in the traditional type of contracts in which the contract is awarded to the lowest bidder.This procurement strategy is adopted by majority of government projects in developing countries.The Latham Report (Latham, 1994) suggested that ensuring timely delivery of projects is one of the important needs of clients of the construction industry.Severe criticisms of the industry arise if it takes much longer than the stipulated project time (Bennett et al., 1979;Flanagan et al., 1986).Completing projects on time is an indicator of an efficient construction industry (NEDO, 1988).Contractors are primarily concerned with quality, time and cost and yet the majority of construction projects are procured on the basis of only two of these parameters, namely time and cost (Bennet and Grice, 1990).The literature emphasises time as an indicator for project success.
The construction process can be divided into three important phases, i.e. project conception, project design and project construction.Usually, the vast majority of project delays occur during the 'construction' phase, where many unforeseen factors are always involved (Chan and Kumaraswamy, 1997).In construction, delay could be defined as the time overrun either beyond completion date specified in a contract, or beyond the date that the parties agreed upon for the delivery of a project.It is a project slipping over its planned schedule and this is a common problem in construction projects.To the owner, delay means loss of revenue through non availability of production facilities and rentable space or a dependence on present facilities.In some cases, delay causes higher overhead costs to the contractor because of longer work period, higher material costs through inflation, and due to labour cost increases.Completing projects on time is an indicator of efficiency, but the construction process is subject to many variables and unpredictable factors, which result from many sources.The sources are the performance of parties, resources availability, environmental conditions, involvement of other parties, and contractual relations, and the completion of a project within the specified time is rare (Assaf, 2006).
Cost and schedule overruns occur due to wide range of factors.If project costs or schedules exceed their planned targets, client satisfaction would be compromised.The funding profile no longer matches the budget requirement and further slippage in the schedule could result (Kaliba et al., 2009).According to Ahmed et al. (2002), delays on construction projects are a universal phenomenon and road construction projects are no exception.Delays are usually accompanied by cost overruns.These have a debilitating effect on contractors and consultants in terms of growth in adversarial relationships, mistrust, litigation, arbitration, cash-flow problems, and a general feeling of trepidation towards other stakeholders (Ahmed et al., 2002).This problem is not unique to developed countries and is being experienced in most of the developing economies.
When projects are delayed, they are either extended or accelerated and therefore, incur additional cost.The normal practices usually allow a percentage of the project cost as a contingency allowance in the contract price and this allowance is usually based on judgment (Akinsola, 1996).Although the contract parties agree upon the extra time and cost associated with delay, in many cases there are problems between the owner and contractor as to whether the contractor is entitled to claim the extra cost.Such situations result in questioning facts, causal factors and contract interpretations (Alkass et al., 1996).Therefore, delays in construction projects cause dissatisfaction to all parties involved and the main role of the project manager is to make sure that projects are completed within the budgeted time and cost.Several studies have been undertaken on factors causing delays and cost overruns, and affecting quality, safety and productivity, etc. and specific problems in special types of projects.These studies usually focus on specific aspects of project performance.Practitioners need to develop the capacity to foresee potential problems likely to confront their current and future projects.Identification of the common problems experienced on past projects in their construction business environment is a good option (Long et al., 2004).Frimpong et al. (2003) revealed that project management tools and techniques play an important role in the effective management of a project.PMBOK defines Project Management as the application of knowledge, skills, tools and techniques to project activities to meet the project requirements (PMI, 2008).Project management involves managing the resources-workers, machines, money, materials and methods used (Giridhar and Ramesh, 1998).Some projects are effectively and efficiently managed while others are mismanaged, incurring much delay and cost overruns.Any construction project comprises two distinct phases: the preconstruction phase (the period between the initial conceptions of the project to awarding of the contract) and the construction phase (period from awarding the contract to when the actual construction is completed).Delays and cost overruns occur in both phases.However the major instances of project overruns usually take place in the construction phase (Frimpong et al., 2003).
Unfortunately, due to various reasons, project successes are not common in the construction industry, especially in developing countries.From several studies and empirical evidence it is clear that project overruns comprising delays and cost overruns occur during the 'construction' phase.Therefore, professionals and scholars have been motivated to take steps to meet this challenge.

Review of Construction Delays across the World
Realistic 'construction time' has become increasingly important because it often serves as a crucial benchmark for assessing the performance of a project and the efficiency of the contractor (Kumaraswamy and Chan, 2002).This study aims to identify the uncertainties and to foresee potential problems likely to confront the current and future projects, helping project teams to be proactive in managing their projects in which potential problems are fully anticipated (Long et al., 2004).
Research literature from all around the world has been collated and consolidated for the better understanding and to conceive the overall picture of the issues.This critical review is presented in five sections; Firstly Identification of Factors and Category, Secondly the Research Methodology adopted in earlier studies (reorganizing and tabulating the data from literature), Thirdly Analysis of Data, Fourthly Results and discussions and Fifthly Conclusions.

Identification of Factors and Category
The factors identified in the research articles are collated and grouped into 18 categories.The set of factors studied by different authors are collected and presented in Table 1.Different authors focus on selected categories for study and analysis.Table 1 tabulates the type of effect studied by different authors and the respective category as classified in their studies.From the review it is observed that certain factors have been categorized under different Groups by different authors.This has been tabulated in detail and discussed in following section of this paper.
The questionnaires were designed to evaluate the frequency of occurrence, severity and the importance of the identified causes (Assaf, 2006).The questionnaire was distributed to Contractors, Consultants and Clients.In the field survey the respondents were asked to indicate the level of importance of each cause using five-point Likert scale ranging from 1 (not important) to 5 (extremely important).The number of firms that completed and returned the questionnaire sets are listed in Table 2 and graphically represented in Figures 1 and 2. Figure 1 shows the total number of questionnaires distributed and the total responses of the individual study.
Figure 2 shows the response rate of individual sectors of respondents in Percentage.

Questionnaire Design and Methods:
The Questionnaire study adopted by each author has a different approach.They have been designed based on previous literature, current construction practice, personal experience and location of the project.Assaf et al. (1995) conducted the investigation in two phases.The first phase included a literature search and interviews.The first phase identified 56 causes of delay.In the second phase a questionnaire was developed using these delay causes.His scope was limited to large public building projects in the Eastern Province of Saudi Arabia.The total population consisted of contractors, architects/engineers (A/Es), and public owners (Government agencies).
Chan and Kumaraswamy conducted two studies in 1997 and 2002.In the earlier study, a pilot study was carried out in early 1994 to investigate the principal causes of construction delay of both building and civil engineering projects which were completed in Hong Kong between 1990 and 1993.The latter survey was supplemented by site visits by industry experts with the aim of identifying the principal factors facilitating faster construction in Hong Kong projects.
Odeh and Battaineh ( 2002) distributed the questionnaire to a random sample of 100 contractors and 50 consultants representing different specializations in large projects.The sample size of each specialization is proportional to the distribution of the population of the different specializations.Given the sample size, the samples were selected randomly from the population in each specialization.Sambasivan and Soon (2007) adopted the same method in their study on the causes and effects of construction delays.Long et al. (2004) developed their questionnaire survey to investigate several issues relating to large construction projects focusing only on the problems experienced.To suit the Vietnam construction conditions, the preliminary questionnaire was pilot tested.Six experienced professionals in the Vietnam construction industry were involved in the pilot test.Their comments were used to revise and prepare the final questionnaire.Responses to the questionnaire were then collected and analysed.The analysis included ranking the problems in terms of degree of occurrence and level of influence.
Frimpong et al. ( 2003) developed a questionnaire of 26 factors designed from previous preliminary investigations conducted in groundwater drilling projects between 1970 and 1999 in Ghana.The questionnaire was directed towards three groups in both public and private organisations: owners of the groundwater projects, consulting offices, and contractors working in the groundwater works.Alaghbari et al. (2007) distributed the questionnaire among government bodies, main contractors, consultants and developers who were connected with the building systems construction projects.In order to accomplish this, the researchers contacted professional institutions, agents and government bodies.The sample was restricted to building system companies.The respondents were contractors, consultant, developers, subcontractors, engineers and architects who were involved in building system construction projects.
All the other studies were conducted by the random sampling of the three principal construction parties (Owners, Consultant and Contractor).Assaf et.al. 1995 Saudi Arabia

Rank correlation coefficient
Where, D= difference between ranks given by one party and the rank given by another party for an individual cause and N= umber of cause or groups.

Assaf et.al. 1995 Saudi Arabia
Relative Importance Index RII where w = weighting given to each factor by the respondentsand ranges from 1 to 5 where '1' is 'not significant' and '5' is 'extremely significant', A = highest weight (i.e. 5 in this case), and N = total number of respondents.

Chan & Kumaraswamy, 1997
Hong Kong Relative Importance Index RII where r = rating given to each factor by the respondents and ranges from 1 to 5 where '1' is 'not significant' and '5' is 'extremely significant', A = highest rating (i.e. 5 in this case), and N = total number of respondents.

Analysis of Data
Each and every study has a different scope and different conclusions.Hence, different approaches have been used and the data analysed with different expressions.Table 3 includes the expressions used by individual researchers to produce the results to meet the set objectives.It shows the data analysis approaches with abbreviations and the equations used to calculate the results.The table explains the parameters used in the expressions.The place where the study was performed is denoted in column 6 of the Table 6.

Results and Discussions
The data from the responses were analyzed by the authors of each and every study and the groups were ranked as shown in Table 4.
It has collective listing of 18 different Groups/Category.The respective rankings results of the studies have been summarized to obtain an over view on the Groups that are highly responsible for the project delays.
The review findings shows that the group and factor ranking differs based on the location like Hong Kong, Jordan, Vietnam, etc. Sambasivan and Soon (2007) stated that "the effects of delays in construction projects can be country-specific" whereas other studies has proven that project characteristics may even be region-specific.None of the studies is comparable to any other and each study has different rankings for the groups/categories/sources of the delays and cost overruns.The groups most influential in earlier studies (in 1995) are now ( 2010) not considered high risk factors.The possible variations in the ranking results are most unlikely to be because of the different respondents.Table 4 clearly outlines that the studies have yielded different results.Even Sambasivan & Soon (2007) adopting the same 28 factors derived by Odeh & Battaineh (2002) has obtained different results of group influence and their responsible levels.Figure 3 shows the scatter diagram of the ranks obtained from the various related studies.
As there is no correlation in the ranking of the different studies, the first five rankings influencing project delays and cost overruns from the entire set of results of each author has been collected.In the different studies the groups with Rank 1 to Rank 5 has been listed.The groups which appear more than once have been identified.This is tabulated in Table 5.
Even though the groups like Owner (Rank 1), Contractor (Rank 2), Design related and Plant and Equipments (Rank 3), Labour (Rank 4) and Consultant and Contractual relationships (Rank 5) fall more frequently within the first 5 rank category, other groups like Finance related, Materials, Schedule and Controlling, Coordination, Changes are also found in some studies but occurs only once in the collated studies.So out of all 18 categories 7 categories appears among the first five ranks and other 11 categories are rated consistently below Rank 5.This provides an overall view of the study, and is shown in Table 5.
The critical review has resulted in a consolidated list of factors/causes and their ranking (Table 6).This review study has identified 113 factors from the studies discussed in this article.Further analysis ranked all these factors according to the results in the respective studies.Table 6 compares the results of ten studies in 12 different sectors of the projects.The corresponding Factors and their Group wise categories are mentioned in the last column of the table 6.This comparative study brings together the results of various studies and combines the Factors / Causes, Ranking and Group classification.
From the list of factors obtained in Table 6 from the previous studies, the first five important causes of delay and cost overruns in different developing countries are determined and summarized in Table 7.
The problem of delays in the construction industry is a global phenomenon.In Saudi Arabia, Assaf and Al-Hejji (2006) found that only 30% of construction projects were completed within the scheduled completion dates and that the average time overrun was between 10% and 30%.In Nigeria, Ajanlekoko (1987) observed that the performance of the construction industry in terms of time was poor.Odeyinka and Yusif (1997) have shown that seven out of ten projects surveyed in Nigeria suffered delays in their execution.Ogunlana and Promkuntong (1996) conducted a study on construction delays in Thailand.Al-Momani (2000) carried out a quantitative analysis on construction delays in Jordan.Frimpong et al. (2003) conducted a survey to identify and evaluate the relative importance of the significant factors contributing to delay and cost overruns in Ghana groundwater construction projects.Chan and Kumaraswamy (1997) studied delays in Hong Kong construction industry.

Conclusions
The critical review undertaken in this paper covers research studies in the area of construction delay with time and cost risks.Totally 18 categories of causes were identified from the various related studies reported in the literature.These 18 categories or Groups are (1) Financerelated, (2) Project-related, (3) Project Attributes, (4) Owner/Client, ( 5 Generally, all the research studies were conducted by questionnaire surveys using randomly sampled responses and analysis of data obtained from the responses.The review study has ranked the responsible groups by combining the analysis results which are: Owner (Rank 1), Contractor (Rank 2), Design related and Plant and Equipments (Rank 3), Labour (Rank 4) and Consultant and Contractual relationships (Rank 5).These fall into the first 5 rank categories.
Each study has a unique approach and unique results are derived from the questionnaire response data.Various indices like Importance Index (I), Rank Correlation Coefficient, Relative Importance Index (RII), Frequency Index (FI), Severity Index (SI) and Mean Score (MS) have been determined to assess the impact of the Factors at various angles based on the requirement for the project.
Each study has rated the groups or factors with Ranks of influence.These ranks are compared for better understanding.But two studies have similar rating of ranks.Each and every Group in the various studies arrived at different weights of Ranks.It would appear that the Groups and Factors causing delays are country, location and project specific and that there are no root causes that can be generalised.

Figure 1
Figure 1 Total number of questionnaires distributed and response Ramanathan, C et al. (2012) 'Construction delays causing risks on time and cost -a critical review', Australasian Journal of Construction Economics and Building, 12 (1respectively; xi = frequency of the ith response given as a percentage of the total response for each cause; i = response ategory index. RII Where i = response category index, Wi = the weight assigned to the ith resonse.Xi = frequency of the ith response given as percentage et al. (2012) 'Construction delays causing risks on time and cost -a critical review', Australasian Journal of Construction Economics and Building, 12 (15 where '1' is 'not significant' and '5' is 'extremely significant', A = highest weight (i.e. 5 in this case), and N = total number of respondents.from 0 for No happen to 4 for Always), n = frequency of each response, N = total number of responses.Le-Hoai et al. 2008 Vietnam Severity Index (%) S.I. (%) a = constant expressing the weight assigned to each responses (ranges from 0 for No happen to 4 for Always), n = frequency of each response, N = total number of responses.Le-Hoai et al. 2008 Vietnam Relative Importance Index RII Le-Hoai et al. 2008 Vietnam ) Contractor, (6) Consultant, (7) Design-related, (8) Coordination, (9) Materials, (10) Plant/Equipment, (11) Labour/Manpower, (12) Environment, (13) Contract-related, (14) Contractual relationships, (15) External, (16) Changes, (17) Scheduling & Controlling and (18) Governmental relationship.

No. Category No. of causes / factors / problems Type of Effect Studied References
Ramanathan, C et al. (2012) 'Construction delays causing risks on time and cost -a critical review', Australasian Journal of Construction Economics and Building, 12 (1) 37-57 41 Table 1 cont'

Table 2 Details of the Questionnaire distribution in various studies and their response
Ramanathan, C et al. (2012)'Construction delays causing risks on time and cost -a critical review', Australasian Journal of Construction Economics and Building, 12 (1) 37-57 44 * The decimals more than 0.5 are rounded to next whole number

Table 6 Consolidated list of Factors / Causes and their Ranking
* (Due to unfamiliarity with local conditions and environment) #(Design & Build, General Contracting, turnkey, etc.)