Causes and Effects of Delays in Construction of Medium Scale Drinking Water Supply Projects in Sri Lanka

Transcription

1 Annual Transactions of IESL, pp. [ ], 2012 The Institution of Engineers, Sri Lanka Causes and Effects of Delays in Construction of Medium Scale Drinking Water Supply Projects in Sri Lanka W.D.A. Perera and R.U. Halwatura Abstract: Most of the infrastructure developments are carried out on project basis. Construction projects frequently suffer from delay, though there are many sophisticated tools and techniques available for construction project management. This paper presents the results of a questionnaire survey conducted to identify and rank the causes and effects of delays in construction of medium scale drinking water supply projects in Sri Lanka. Both Severity Index () and Frequency Index () were used to rank the importance of the factors and the findings of the study indicate that inclement weather conditions, contractors financial difficulties, shortage of labour, rules and regulations of road authorities, delays in sub contractors work, material import delays and ineffective planning and scheduling of projects by contractors are among the most important factors causing delay in construction of medium scale drinking water supply projects. Moreover, time overruns, cost overruns, funding difficulties, development of unfair relationships among the parties and disputes are the most important effects due to delay. Delays are costly for both clients and contractors and often result in disputes and claims. Therefore in order to improve the situation and avoid /mitigate delays in projects, several prescriptions are recommended for clients and contractors. Keywords: Water supply projects, Causes and effects of delays, ing of delay factors 1. Introduction In Sri Lanka, a considerable amount of the national budget on infrastructure development is channelled to water supply sector and at present only around 37 percent of the population have access to pipe borne water [1]. The demand for pipe borne water is growing continuously with the increased level of urbanization, change in lifestyles and expansion of commercial and industrial activities. National Water Supply & Drainage Board is responsible for supplying pipe borne drinking water to the nation. The operation and maintenance of existing water supply schemes and the implementation of projects to construct new schemes to meet the growing demand due to urbanization are among the major tasks of it. In recent past, number of water supply projects that had been planned to supply water to developing areas in and around major cities of the country has failed to meet the time targets due to various reasons and affected the socio-economic development of the country. Most of the infrastructure developments are carried out on project basis. Every construction project has a defined goal or objective, defined tasks to be performed and a defined time frame and also every construction contract considers time as the essence of the project. Delay is a situation when the contractor and the project owner jointly or individually contribute to the non-completion of the project within the original or the stipulated or agreed contract period [2]. Delays in construction projects are frequently expensive, as they are usually involved with construction loans which charges interest, management staff dedicated to the project whose costs are time dependent and ongoing inflation in wage and material prices [3]. Some projects are susceptible to delay due to their nature and water and sewerage projects are in this category with several influential factors causing delays. These factors include; the projects are taken place in public roads and streets where special precautions are required, high uncertainty associated as they require Eng. W D Anuruddha Perera, B.Sc.Eng.(Hons), M.Sc.(CPM), C.Eng., MIE(Sri Lanka), Chief Engineer, National Water Supply & Drainage Board, Avissawella. Eng. (Dr.) R U Halwatura, BSc Eng. (Hons), PhD, CEng., MIE(Sri Lanka), AMSSE, Senior Lecturer, Civil Engineering Department, University of Moratuwa. 151

2 excavation and trenching works in varied soil and site conditions, works are heavily dependent on equipment and machineries, which are susceptible to repairs and need to get approvals from various authorities [4]. Further, the procedures in issuing of approval certificates for excavation for trenching from government authorities are complex and time consuming due to lack of coordination and various other reasons [5]. There are different perceptions among the major parties involved in projects regarding the causes of project delays. Both contractors and consultants agree that owner interference, inadequate contractor experience, financing and payments, labour productivity, slow decision making, improper planning and sub-contracting are among top ten causes of construction delays in traditional contracts [6]. In most of the developing countries, infrastructure development projects are implemented through the major government authorities that still act as traditional organizers and strictly bound to follow government rules and regulations on procurement. There are a lot of criticisms on the inefficiencies of these government institutions regarding project implementation. The Contractor s improper planning is the major cause of delay in Malaysian construction industry [7]. According to this study, contractors often fail to come out with a practicable and workable work program at the initial planning stage and this failure is interrelated with lack of systematic site management and inadequate contractor s experience towards the projects. On the other hand, the significant factors causing delays in Hong Kong construction projects are: poor site management and supervision, unforeseen ground conditions, low speed of decision making involving all project teams, client initiated variations and necessary variations of work [8]. Further, the most significant problems causing construction project delays in Thailand includes lack of resources, poor contractor management, shortage of labour, design delays, planning and scheduling deficiencies, change orders and contractors' financial difficulties[9]. Moreover, delayed payments, financial processes and difficulties on the part of contractors and clients, contract modification, economic problems, materials procurement, changes in drawings, staffing problems, equipment unavailability, poor supervision, construction mistakes, poor coordination on site, changes in specifications and labour disputes and strikes were found to be the major causes of schedule delay in road construction projects in Zambia [10]. Both the project owners and contractors suffer from the delays. The owner loses his money due to increased overheads for supervision, contract administration and also delaying the use of the final product or result of the project [4]. On the other hand, the contractor losses may be the lost opportunities for new projects, increased overheads, etc. But, most of the construction projects suffer from delay, though there are many tools and techniques available for project management. However, there are only few previous studies available on this topic and related to our construction projects. Therefore, there is a need for more efforts to identify the causes and effects of delays in different types of construction projects in Sri Lanka and made awareness of the relevant parties involved to avoid or minimize them and complete the projects successfully. 2. Objectives of the Study To identify and rank causes and effects of delays in construction of medium scale drinking water supply projects in Sri Lanka. To study the difference in perceptions of the two major parties involved in construction of drinking water supply projects namely clients and contractors on causes and effects of delays in construction of medium scale drinking water supply projects. Propose measures to mitigate delays in construction of medium scale drinking water supply projects. 3. Research Methodology A detailed literature review was carried out to identify the previous studies in the research area and found the major causes and effects of delays in projects in Sri Lanka and other counties. Then, a careful identification of the factors related to the study were done and a survey questionnaire was developed to assess 152

3 the perceptions of contractors and clients who were involved in construction of medium scale water supply projects on the relative importance of causes and effects of construction delays. The questionnaire consisted of four parts; part I- respondents details, part II causes of delays, part III effects due to delays, part IV mitigation actions. The first part of the questionnaire requested the respondents general details while the second part of the questionnaire consisted of thirty nine causes of delay that were categorized under seven major groups: i. Project related: Inadequate project duration, Improper contract formulation (large Nos. of contracts for a single project, intake civil construction work included in a pump contract, etc.),type of project bidding and award (tendency in awarding the contracts to lowest bidder) ii. Owner/consultant related: Delay in progress payments by owner, delay in handing over the site to the contractor, delay in approval of shop drawings and samples, delay in inspection and testing of works, Inadequate Liquidated damages, too many change orders, slow decision making, poor contract management of owner/consultant. iii. Contractor related: Contractors financial difficulties, mistakes during construction and rework, shortage of project staff with required experience, Poor coordination/communication by the contractor with other parties, Ineffective planning and scheduling of project by contractor, improper construction methods implemented by contractor, delays in sub contractors work, insufficient delegation of power to the site management team. iv. Design related: Delays in producing construction drawings, unclear and inadequate details in drawings, mistakes and discrepancies in drawings and bills of quantities, inadequate specifications for materials. v. Materials related: Shortage of construction materials in market, changes in material types and specifications during construction, restrictions on issuing permits to transport materials, rejection of imported materials due to non-compliance with the contract specifications. vi. Equipment and Labour related: Frequent equipment breakdown, shortage of equipment and hiring delays, low productivity and efficiency of equipment, low productivity level of workers, shortage of labour, labour union actions. vii. External factors: Inclement weather conditions, delay in obtaining permits, services, etc. from local authorities and other organizations such as electricity board, traffic/security problems, changes in government regulations and laws, rules and regulations of Road Development Authority(RDA), Provincial Road Development Authority (PRDA) and local government authorities (PS) on road excavation work approvals. The third part of the questionnaire consisted of the effects due to delay checklist: Time overrun cost overrun, dispute, arbitration, litigation, total abandonment, funding difficulties, delay in commissioning other related projects and develop unfair relationships with other organizations such as RDA, PRDA, PS, etc. The last part of the questionnaire is for getting the respondents prescriptions to reduce delays in projects. For each cause/effect two questions were asked: what is the frequency of occurrence for this cause? and what is the degree of severity of this cause on project delay? Both frequency of occurrence and degree of severity were categorized on a four point scale. Frequency of occurrence was categorized as: Rarely, Sometimes, Often and Always. Similarly, degree of severity was categorized as: Little, Moderate, Great and Extreme. In Sri Lanka, almost all the medium scale drinking water supply projects are carried out by the National Water Supply and Drainage Board and the contractors are involved in these developments. The questionnaire was distributed among the professionals of the above two groups and the sampling method used in this study was convenience and snowball sampling that comes under the class of non-probability sampling techniques [7]. 3.1 ing of delay factors The ranking of causes and effects of delays from the viewpoints of three parties involved in construction projects; owners, contractors and consultants can be done using three indices; frequency index, severity index and importance index [11]. The similar method was applied in the study and the following equations were used for the calculation of three indices. Frequency index () is a formula 153

4 used in the study to rank causes of delay based on frequency of occurrence as identified by the participants. : () (%) = a (n/n)*100/4 (1) where, a is the constant expressing weighting given to each response (ranging from 1 for rarely up to 4 for always), n is the frequency of the responses, and N is total number of responses. Severity Index () is a formula used in the study to rank causes of delay based on severity as identified by the participants. () (%) = a (n/n)*100/4 (2) where a is the constant expressing weighting given to each response (ranges from 1 for little up to 4 for severe), n is the frequency of the responses, and N is total number of responses. Importance Index (IMPI) of each cause is calculated as a function of both frequency and severity indices. (IMPI) (%) = () (%) *() (%) (3) 4. Data analysis 4.1 Sample Characteristics The questionnaires were distributed to a sample of professionals of the two major parties (clients and contractors) involved in the projects by hand delivery, regular mail and also via internet. The survey was carried out over the period from August 2010 to October 2010, and the response rate and the basic qualifications of the sample were as shown in the Tables 1 and 2. Table 1- Questionnaire Response Rate Category Client Contractor Total Hand Regualr Via Questionnaire sent Total delivery mail Internet Nos. of participants Nos. of respondents Response rate% Nos. of participants Nos. of respondents Response rate% Nos. of participants Nos. of Respondents Response rate % Data Analysis The responses to the questionnaires were analyzed from client s, contractor s and overall perspectives based on severity and frequency of occurrence of the causes and effects to identify the most important causes and effects of delays. The ranking indices were calculated using the three formulas stated under methodology and are presented in Tables 3 and 4. Table 2 - Respondent s Qualifications Category Client Contractor Total Basic Qualification No. of Respondents % Dip B.Sc M.Sc Ph.D Dip B.Sc M.Sc Ph.D Dip B.Sc M.Sc Ph.D Discussion of Results This section discusses the results obtained in the analysis. First, the results obtained by analyzing the causes of delay in construction of medium scale water supply projects were discussed and compared the client, contractor and overall perspectives. Then, the results obtained by analyzing the effects due to delay were discussed. 5.1 Causes of Delay The importance of the identified thirty nine causes of delay in construction of medium scale water supply projects were depended on both the severity and frequency of occurrence. Severe delay factors The results of the analysis show that the clients ranked ineffective planning and scheduling of the project by contractor (=87.79), contractor s financial difficulties (=84.30) and rejection of imported materials (=83.72) as the most severe causes of delay while the contractor considers weather conditions (=90.00), delays in sub contractors work (=89.38) and delay in progress payments by owner (=88.13). This shows that there is a disagreement between the two parties regarding the most severe causes of delays. In Sri Lanka, almost all the medium scale water supply projects are implemented through National Water Supply & Drainage Board and funded by either the capital budget or foreign donor funds. 154

5 Table 3 - ing of Causes of Delay Table 4 - ing of Effects due to Delay Causes of delay Inde Inde Inde Project related 1 Inadequate Contract duration Improper contract formulation Tendency in awarding the contracts to lowest bidder Owner/consultant related Delay in progress payments by owner Delay in handing over the site to the contractor Delay in approval of shop drawings and samples Delay in inspection and testing of works 8 Inadequate application of Liquidated damages Too many change orders Slow decision making Poor contract management of owner/consultant Contractor related financial difficulties Mistakes during construction and rework 14 Shortage of project staff Poor coordination/ communication Ineffective planning and scheduling of project Improper construction methods Delays in sub contractors work Insufficient delegation of power to the site Design related 20 Delays in producing construction drawings 21 Unclear and inadequate details in drawings 22 Mistakes and discrepancies in drawings and BOQ Inadequate specifications for materials Materials related 24 Shortage of construction materials Material import delays (Pipes, fittings, etc.) Changes in material types and specifications Restrictions on issuing permits to transport materials. 28 Rejection of imported materials Equipment and Labour related 29 Equipment breakdown Shortage of equipment and hiring delays Low productivity and efficiency of equipment 32 Low productivity level of workers Shortage of labour Labour union actions External factors Factor Description 35 Inclement weather conditions Delay in obtaining permits, services, etc. 37 Traffic/security problems Changes in government regulations and laws 39 RDA, PRDA, PS. rules and regulations Client Contractor Overall No Effects due to delay Contractor's view Client's View Overall view Index Index Index 1 Time overrun Cost overrun Dispute Arbitration Litigation Total abandonment Funding difficulties Delay in commissioning other related projects Develop unfair relationships with 9 other organizations such as RDA, PRDA, PS,etc. Source: calculated from survey data There is a high competition in the industry and most of the contracts are awarded to lowest bidders who are normally having a little profit margin. There are delays in monthly progress payments to the contractors due to the financial difficulties faced by the client. Hence, the work progress can be delayed. Frequent delay factors Frequency of occurrence of delay factors is also a significant aspect, which uses to determine the importance of causes of delay. The client ranked Ineffective planning and scheduling of project by contractor ( 92.44) as the most frequent factor causing delays in construction of medium scale water supply projects while it is inclement weather conditions for both contractor s ( 91.25) and overall ( 88.6) rankings. The inclement weather conditions badly affect the construction of water supply projects and in sometimes it will cease the construction activities until the weather becomes normal [12]. This supports the findings of the research and reconfirms that inclement weather is a frequent cause of delay in construction of water supply projects and the project teams should draw special attention to the inclement weather conditions at the planning, design and construction stages of the medium scale water supply projects. Further, the delay factors such as RDA, PRDA, and PS rules and regulations on road excavation work approvals, material import delays (pipes, fittings, etc.) that occur due to the nature of water supply projects are identified by clients as well as contractors as frequent causes of delay and ranked within first ten positions. Moreover, both the clients and the contractors ranked the delay factors 155

6 labour union actions and changes in government regulations and laws as very rare causes of delay in construction of medium scale water supply projects although in some other sectors in Sri Lanka union actions are very frequent. One of the reasons for this is less opportunities in the construction industry to organize for bargaining for their benefits. But in the recent past the union actions of clients professional staff had been affected project activities and there had been delays in extra work approvals, tender evaluations, tender awarding, and etc., which caused delays in construction of water supply projects. The construction of water supply projects requires getting various types of approvals from government institutions. Due to improper coordination with these organizations, it has been facing difficulties in getting these approvals on time. The delays in getting approvals for road excavation that requires for pipe laying in public roads have been identified as a frequent causes of delay in construction of water supply projects. Further, the introduction of new rules and regulations of Road Development Authority (RDA) on road reinstatement after trenching has severely affected the implementation of water supply projects, as it requires some time to adjust to new requirements and take necessary policy decisions to develop relevant systems to carry out the works. Therefore early attention should be drawn in this regard and develop some effective and efficient systems to handle RDA requirements and provide necessary provisions in contracts to do the temporary as well as permanent road reinstatement. Important delay factors The results of the analysis show that there are several important factors underlying causes of delay in construction of medium scale water supply projects in Sri Lanka. Ten most important delay factors as identified by clients, contractors and overall view are presented in Table 5. Contractors ranked inclement weather conditions first, whereas the clients ranked it fourth. The construction of medium scale water supply projects normally includes construction of head works, laying of transmission and distribution systems and construction of office, stores and other facilities. Table 5 - Important Delay Factors Client s view Contractor s view 1 Ineffective Inclement planning and weather scheduling of conditions project by contractor 2 Contractors financial difficulties 3 Shortage of labour 4 Inclement weather conditions 5 RDA, PRDA, PS. rules and regulations on road excavation work approvals 6 Material import delays (Pipes, fittings, etc.) 7 Delays in sub contractors work 8 Delay in handing over the site to the contractor 9 Too many change orders 10 Delay in obtaining permits, services, etc. from local authorities and other organizations such as Electricity Board. Delays in sub contractors work RDA, PRDA, and PS rules and regulations on road excavation work approvals Delay in progress payments by owner Inadequate contract duration Material import delays (pipes, fittings, etc.) Mistakes and discrepancies in drawings and bills of quantities Shortage of labour Unclear and inadequate details in drawings Slow decision making Overall view Inclement weather conditions Contractors financial difficulties Shortage of labour RDA, PRDA, PS. rules and regulations on road excavation work. Delays in sub contractors work Material import delays (Pipes, fittings, etc.) Ineffective planning and scheduling of project by contractor Too many change orders Delay in handing over the site to the contractor Delay in obtaining permits, services, etc. 156

7 The inclement weather affects most of these works, and especially for pipe laying works and intake construction works. Contractor s ineffective planning and scheduling of the project will make worse the situation if he does not consider or fails to predict the weather pattern at the initial planning. Skills and experience of workforce, management, job planning, workers motivation, and material availability were the major drivers of productivity of water and waste water treatment plant construction works [13]. It is essential to draw special attention to these factors and apply in projects as this will help to speed up of the works and also help to expedite the delayed works due to various causes identified in this study. Agreement among groups The degree of agreement between the clients and contractors on causes of delays in projects was calculated using spearman s rank correlation coefficient. The equation, r s = 1- (6 d 2 /N(N 2-1)) was used to calculate this coefficient when there are no tied links [14]. Where r s = Spearman s rank correlation coefficient, d = the difference in ranking between the clients and the contractors and N = the number of variables. The spearman s correlation coefficient calculated was 0.55 for the causes of delays ranked by the clients and contractors. Spearman s rank correlation coefficient equals to +1 means that two variables are having perfectly positive correlation while -1 gives perfectly negative relationship. The somewhat low value of rank correlation coefficient (0.55) indicates low agreement between clients and contractors on the ranking of the factors. This low agreement has created disputes between the parties and the most delays occur at the project construction phase. 5.2 Effects due to Delay Clients as well as contractors ranked, total abandonment as the most severe effect due to delay in construction of medium scale water supply projects and the severity indices calculated for them are 94.8 and 96.9, respectively. But they ranked it as a very rare effect due to delay and the frequency indices are 29.1 and 28.8, respectively. This depicts that though there are delays in construction of medium scale water supply projects due to many reasons, the relevant organizations have taken measures to complete the projects without abandonment. Further, the clients and contractors agreed that time overruns and cost overruns are among the most severe effects due to delay. These effects may lead to other effects such as disputes, funding difficulties, delay in commissioning related projects, etc. On the other hand, both clients and contractors agreed that time overruns, cost overruns and disputes are the most frequent effects due to delay in construction of medium scale drinking water supply projects in Sri Lanka. Most of the delay factors, which were categorized under seven sections in this study, affect the completion of the projects and cause time overrun, cost overrun and disputes. Similar effects have been identified as the most frequent effects due to delays in Nigerian construction industry through a study carried out concentrating the building construction industry [15]. This study mainly recommended providing sufficient contingency provisions in total cost estimates to handle the project uncertainties. As the construction of water supply projects also faces a lot of uncertainties due to their nature [4], it is better to consider this recommendation and decide contingency percentages wherever necessary after carefully considering the requirements rather than providing fixed percentages from the contract value. The importance of the effects due to delay the same as the importance of causes of delay is determined by considering both severity and frequency of occurrence. Hence some effects due to delay, which were having higher frequency indices with low severity indices, were ranked as the lesser important factors. As an example, Disputes has the highest frequency index of 88.6% and the least severity index of 44.0% as per the overall view, were ranked at 5 th as per the importance with 38.94% importance index. Therefore the identification of these effects due to delay based on the above three indices will help the project management to select the causes of delay, which requires more attention based on their consequences. 157

8 6. Conclusions and Recommendations There are delays in construction of medium scale drinking water supply projects in Sri Lanka. As per the overall view inclement weather conditions, contractors financial difficulties, shortage of labour, rules and regulations of road authorities and delays in sub contractors work are the first five important factors causing delays in projects. Further, both clients and contractors agree that rules and regulations of road authorities and inclement weather conditions are among the most important delay factors. On the other hand, as per the overall view inclement weather conditions, mistakes and discrepancies in drawings and bills of quantities, rules and regulations of road authorities, delay in obtaining permits services, etc. and contractor s financial difficulties are the most frequent causes of delay while rejection of imported materials due to noncompliance with contract, delay in subcontractors work, delay in progress payments by owner, contractors financial difficulties and shortage of labour are ranked as the most severe causes of delay. On the other hand, time overruns, cost overruns, funding difficulties, disputes, arbitration, litigation, delay in commissioning related projects, total abandonment and develop unfair relationships with road authorities are the effects due to delay in projects. Both clients and the contractors felt that time overruns, cost overruns, funding difficulties and develop unfair relationships with other organizations appear to be the most important effects due to delay in construction of medium scale water supply projects. As per the overall view, disputes and time overruns are the most frequent effects while total abandonment and time overruns are the most severe effects due to delay. A proper understanding of these causes of delays and their consequences will help the relevant project professionals to better manage delay situations in construction of medium scale water supply projects. Further, based on the study, the following prescriptions are recommended for clients and contractors to avoid/mitigate delays in construction of medium scale drinking water supply projects. Prescriptions for Contractors Contractors must consider their financial capabilities before bidding projects and should employ a qualified staff for the financial management of projects. Contractors should not take up the job in which they do not have sufficient expertise. Contractors should employ qualified and well experienced site staff during the project period. The planning and scheduling of the project should be done properly and the revision of the schedules has to be done as required. When employing sub-contractors it has to be done after considering his capabilities and by entering into a formal agreement. Contractors should keep site records properly. Contractors should submit their claims as per the requirements given in the contract. Prescriptions for Clients Contractors should not be selected based only on the lowest bid. The client should consider contractor s experience in similar works and his technical and financial capabilities, before awarding the contracts. It is necessary to decide realistic project durations by the client considering various aspects. The client should take necessary measures to use qualified and experienced professionals for planning and designs of projects. The clients must take necessary actions to handover the possession of site to the contractors without delay. The client should employ a capable and well experienced project staff for the construction stage. They have to closely monitor the progress of work and propose necessary steps to expedite the works to the contractor if the progress is behind the schedule. Appropriate total cost estimates should be prepared at the initial stage of projects and the client should settle the contractors claims without delay. Enforcing liquidated damage clauses and offering incentives for early completion. 158

9 Minimize change orders during construction to avoid delays. The client should coordinate with other organizations such as local authorities, road authorities and various other government organizations at various stages of projects. 6.1 Recommendations for Future Studies Similar study can be conducted for other types of infrastructure development projects such as road development projects, telecommunication projects, power generation projects, etc. and compare the similarities and differences of causes and effects of delays in these projects. References 1. Report, C. B. (2010), Central Bank Report, pp Levy, S. M. (1994), Project Management in Construction. Mgraw-Hill Inc.USA, pp Trauner, T.J., Construction Delays, Publisher, Butterworth Heinemann, pp , Al-Khalil, M., & Al-Ghafly, M., Delay in public utility projects in Saudi Arabia. International Journal of Project Management, pp , Chabota Kaliba, A, Cost escalation and schedule delays in road construction projects in Zambia. International Journal of Project Management, pp , Assaf, S., & Al-Hejji, S., Causes of delay in large construction projects. International Journal of Project Management, pp , Frimpong, Y., Oluwoye, & Crawford, L., Causes of delay and cost overruns in construction of ground water projects in developing countries; Ghana as a case study. International Journal of Project Management, pp , Mojahed, S., & Aghazadeh, F., Major factors influencing productivity of water and waste water treatment plant construction: Evidence from the deep South USA. International Journal of Project Management, pp , Dowdy, S., & Wearden, S., Statistics for research. New York: John Wiley & Sons, pp , Aibinu, A., & Jagboro, G., The Effects of Construction Delays on project delivery in Nigerian Construction Industry. International Journal of Project Management, pp , Luu, V., Kim, S., Tuan, N., & Ogulana, S., Quantifying schedule risk in construction projects using Baysian belief networks. International journal of project management, pp , Odeh, A., & battaineh, H., Causes of construction delay: traditional contracts. International Journal of Project Management, pp.67-73, Sambasivan, M., & Soon, Y., Causes on effects of delays in Malaysian Construction Industry. International Journal of Project Management, pp , Chan, D., & Kumaraswamy, M., A comparative study of causes of time overruns in Hong Kong construction projects. International Journal of Project Management, pp.55-63, Toor, S., & Ogunlana, S., Problems causing delays in major construction projects in Thailand. Construction Management & Economics, pp ,