Impact of Variation Orders on Cost and Time in public and Industrial Projects
(Company Case Study)
This research proposal has a major focus on the change orders in both the public and private construction projects in gulf countries. Further, the proposal shall use questionnaires surveying the construction managers, contractors and consultants in the construction industry. The data collection techniques with the help of questionnaires will help in the demonstration of the characteristics of the construction industry. In addition, the introduction will outline the background information in the change orders that cause delays and additional overhead costs. The introduction section will also entail the statement of the problem of the research topic. Secondly, the research questions will outline the main areas in the knowledge gap that the research intends to cover as well as the outlining of the study specific objectives. Further, the literature review of the study shall explain relevant works by other researchers who worked on the effects of change orders on delays. The main key words of the study include; causes related to change order, control, effects, construction and overhead costs.
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Variation orders are very common in most construction projects these days, often resulting to an increase in the cost of the project by a particular percentage of the project cost. It is vital to understand the consequences of such trends and it is for this reason that studies have been carried out to determine the impact of variation orders on the cost of the project. The current research investigates the impact of variation orders of cost and time in in Industrial Projects. The research is based on a case study of Arabian company in the gulf. Questionnaires were administered to 20 workers in this construction company and the results analyzed using SPSS. Frequency tables of the demographic statistics were obtained as well as the mean ranks of the different factors for variation orders. The study has established that the main source of variation of orders is the changing of plan by the owners. The other source of variation orders is the change in mind in regard to materials, which are always available. It is also worth to note that consultants also contribute to variation orders. Increase in the cost of a project and duration of the project are considered to be the main effects for variation orders.
Over the years, change orders have seemed to dominate the construction industry as evidenced in the case study of the industrial construction. Change orders can be categorized in three types namely; firstly, the change orders that affect the initial planning stage of a project. Secondly, construction change directives that change the main objectives of the monitoring stage in construction projects and the minor changes that only affect the small related projects in the construction strategies (Hwang and Low 2012, 817). The different phases involved in project planning, implementation and monitoring involve different stakeholders (Bryde, Broquetas and Volm 2013, 971). In this light, the different stakeholders develop dynamic objectives towards the actualization of the project as well as different perceptions on the success of the project (Hwang and Low 2012, 817). Notably, the different views developed make the changes in the project actualization (Han, Love & Peña-Mora 2013, 2044). Project managers have learned to acknowledge the change and developing of mitigation procedures in the reduction of costs that the changes bring (Hwang and Low 2012, 817). In some cases, the change in orders develop severe complications that reduce the probability of success of the project (Bryde, Broquetas and Volm 2013, 974). In addition, a variation from the main goals of the project describe change orders and mostly lead to additional project costs and increments in the cost overruns.
Change order in project management describe the work or phase that added or got lost in the process of actualization of the project (Han, Love & Peña-Mora 2013, 2044). In addition, a change order is a general deviation from the main course of the project motivated by organizational structure, environmental aspects or other external aspects (Marzouk and El-Rasas 2014, 49). The change orders act as a disincentive to the actualization of the project (Bryde, Broquetas and Volm 2013, 974). Moreover, constructors have found that additional paper work and concepts deviate the specific project objectives (Kikwasi 2013, 57). Importantly, some change orders are intended to improve the probability of success of the project through additional ideas, methodologies and interpretations (Hwang and Low 2012, 819). Further, change orders distort the relationship between the owners, the constructors, the subcontractors and the other involved stakeholders (Han, Love & Peña-Mora 2013, 2044). The changes made on the project also have proved to have a negative correlation with the actualization of other related projects and sub-projects (Bryde, Broquetas and Volm 2013, 975). In most cases, the sub-projects have different objectives from the main project but the two share in the final outcome and goal (Hwang and Low 2012, 820). In this light, distortion of the original plan of a project would affect the sub-projects that share in the common goal but do not share in the specific objectives of the main project (Marzouk and El-Rasas 2014, 49).
The change orders introduce delays in the implementation and monitoring of projects. In addition, the costs on industrial constructions tend to rise in the event of negative change orders (Bryde, Broquetas and Volm 2013, 977). Moreover, the workflow of the project is disrupted in the situation where the work schedule relies on the planning phase of the project (Han, Love & Peña-Mora 2013, 2044). Additionally, the study will identify the specific aspects of change orders that affect the performance of the project (Hwang and Low 2012, 822). Clearly, the change orders attribute greatly to either the downfall or the success of a project depending on the direction of both causality and correlation (Bryde, Broquetas and Volm 2013, 977). Additionally, the change orders that will be developed in the study will evaluate their effect on both the delays in project actualization and the additional costs in the industrial constructions (Han, Love & Peña-Mora 2013, 2054). In a nutshell, the research statement of the problem will be the enquiry into the effects of change orders on delays and the costs of industrial construction in projects. Additionally, the theory of consumption expenditure is crucial in explaining the causality tests of the delays and the cost overruns (Hwang and Low 2012, 817).
Change is referred to an event of transforming something to make it different. This transformation is made possible through various modifications by additions or deletions from the original event. Industrial projects undergo several modifications which are referred to as change order. Change orders are often given out to take care of variations in material quantities, scope of the project, errors in designs and changes in unit rate (Arain, 2005). This change order may occur because of several reasons such as a change in scope, change in design, change in work conditions, as well as a change in work quality (Gibson and Ryan, 2000). Change orders have several consequences and impacts on organizations and people regarding cost, time and performance (Arain, 2005). These effects vary depending on the nature and type of change order. Controlling and minimizing change order is necessary and beneficial to the project owners since it increases efficiency and productivity of members (Mokbel, 2003). Project profits are also seen when there is a reduction in percentage change order. Change order needs intense analysis and study to measure the sources and impact of change order in industrial projects. It is risky and difficult to manage change orders, but it should be dealt with and avoided in a project. Therefore, it is necessary to first have knowledge of source or causes of change order before trying to minimize it (Halwatura and Ranasinghe, 2013). Therefore with this knowledge, it is easy to establish mitigations of dealing with the impacts of a change order concerning cost and time.
The efforts of controlling change orders are proving to be a great burden on project management. No industry wishes to experience change orders as a problem since it has a huge negative impacts that affect the performance of the industry. Change orders may also cause ethical disputes and problems. These problems of change order possess an opportunity for research on the impacts of change order on time and cost on industrial projects.
Most of the industrial projects have been facing change order for quite some times. This change order has brought about several impacts on the performance of the projects not only in Arabian construction company, but also in the entire globe. Since change order is inevitable, it is, therefore, necessary to understand factors influencing change order and its impacts on time and cost as well as recommend policies to minimize change order. Qualitative research has been done in the past on the factors influencing change order and its impacts on industrial projects. This has led to lack of quantitative information to draw a framework for sources and effects of change order. This work examines quantitatively the causes and impacts of change order in Arabian construction company and develops a framework to be used in future studies in this field.
To establish the impacts of a change order on cost and time on industrial projects.
- To determine the change order definition.
- To determine the main factors influencing the occurrences of change order.
- To determine the impacts of change order.
- To assess the impact on cost brought by change order.
- To determine the impact of a change order on time
- To find out how owners, contractors and consultants can benefit from the results of the study.
- To formulate a simulation model of change order that can be built on its impact on performance.
- Are there major factors that significantly influence the occurrences of change order?
- Does change order significantly affect industrial projects?
- Does change order have any significant impact on the cost of industrial projects?
- Do change orders have any significant effect on time?
- Is there a significant benefit that owners, contractors and consultants can get from the results of the study?
- Is there a simulation model of change order that can be built on its impact on cost and time?
- There are no major factors that significantly influence the occurrences of change order.
- Change order has no significant effect on industrial projects.
- Change order does not significantly affect costs.
- Change order has no significant effects on time in industrial projects.
- Owners, contractors and consultants cannot significantly benefit from the results of the study.
- There is no significant simulation model of change order that can be built from its impact on performance.
The main reason why research has to be advanced in different fields is to help human being solve their day in day out challenges in the world. Therefore, just as any other research, this study is important in the following ways:
- Helps in solving unresolved problems. My main aim is to clearly explant e determinants of a change order managed by Arabian construction company with a strong emphasis on its impacts in industrial projects especially in terms of time and cost.
- Increase body of knowledge. Not only do I believe that this study has made me an expert in this field of change order, but I also think that whoever goes through it will experience a great likeness in a change order and other related phenomena.
The extent of the study is in the Arabian construction company. Although there are many effects brought about by change order, the research focuses on the impacts of change order on cost and time in industrial projects. Other study included relating impact to project professional’s experience using number of projects of the same type, years in industry and number of projects of the same size.
Change: This is the process of transforming an event by either additions or deletions from the original work.
Change order: This is single written order in project management agreed by the owner directing contractors to change contracts, requirements and cost within the scope of work.
Cost: Amount that has been spent to obtain something.
In the course of the research work on change order, we are faced with several limitations as per the proposed research. One of the limitation is that the scope of the survey is enormous hence the lack of uniformity in the data collected. The second limitation focuses on the financial constraints leading to inadequate research materials and personnel, which eventually might influence the inefficiency and ineffectiveness of the research. The other limitations are based on the assumptions made in the research that all the estimates of the change order are accurate and that the estimates of the original research are reasonably accurate.
The basis of any good research is determined by the investigation on prior studies done on it about articles, data analysis techniques, research designs and discoveries during such studies. Change order not being a new phenomenon has been examined in length and its impact verified. This chapter covers some of the empirical analysis and conceptual framework that establishes the relationship between variables.
Change is a process that cannot be avoided to attain successful projects. A variation order in most industrial projects involves modifications of the original framework by either additions or deletions agreed by project owners (Staiti, 2015). These are written orders from the project owners to contractors. Variation order involves a change of requirements, time, amounts and even designs of the projects. Changes are necessary due to lack of money and resources that can be employed in planning hence industrial projects incorporate variation orders to address the unavoidable and unforeseen situation (Kokel, 2015). However, variation orders have a great negative impact on most construction processes such as delays and disputes among involved parties (Choi et al., 2015).
The variation order, therefore, refers to the processes, scope, and project methods that differ from the original work project (Ai-Dubaisi, 2000). These changes are encountered in industrial projects for several reasons including design changes and new scope. In most cases, changes are classified based on the technique used to introduce them such as scope changes, directive changes and effective change (Love, 2002).
In construction projects, a change is referred to as modification or alteration made to original conditions, basic information, original requirements and original assumptions which include cost, time and performance. During execution of work, a change in procedure of construction, planned design and terms of contract may result to variation order (Hanna and Gunduz, 2004).
A variation order is a written order which the owner signs and issues to the contractor after the contract has been executed requesting for change I the adjustment of scope of work and contract time. For an industrial project to be successful, it largely depends on the project professional’s ability to control and manage the variation orders so as to prevent its negative impacts on performance of industrial projects (Camlic and Nordheim, 2002).
In construction projects, various changes are experienced which leads to issuing of variation orders meant to cover for various variations such as changes in material quantities, design errors, and change in unit rate (Arain and Pheng, 2005).
2.3 Legal Aspects of variation Order
There are no doubts that variation order result into serious negative impacts on the performance of a project in terms of cost, time and efficiency. Due to these impacts, specified clauses indicate individuals who are authorized to take decisions. The clauses are found in most contracts. The International Labor Organizations indicates that the engineer of the project has the right to approve a change of original scope. Parties responsible for variation orders may cause damaging impacts including owners causing bad impacts due to failure to understand the objectives of the scope as well as installation of nonconforming work by the contractor (Bubshait, 2003).
Many previous studies show the significant factors affecting the circumstances of change order. Several factors have been highlighted in Table 2.1 below,
|Design Errors||Lack of design expertise||Designers should have better understanding of the project to maintain high quality. Change occurs when designers with lack of skills are employed.|
|Duration||When there are delays in prepared design, then change orders cannot be avoided|
|Requirements of design||The owner may have ambiguous detail specification and requirement of drawing.|
|Designer’s responsibilities||Designer’s responsibility should be determined at a high standard level|
|Specifications||Specifications and procedures reworked for quality implementation should be followed strictly.|
|Scope and quantity of work||Significant change in the quantity of work|
|Scope of the project (Type and nature)||This is a section of project planning involving documentation and determination of project goals, tasks, costs, and deadlines.|
|Methods of work||Best practices and methods|
|Final measurements and calculation||Project sales measured by its estimated values|
|External conditions||Extreme weather conditions|
|Unavailability of materials||This leads to changes due to delays|
Various effects are associated with variation order in industrial projects. Some of the implications of the variation order are discussed in this section.
The cost is significantly affected by variation order. It is possible to calculate the direct change expect in the event of Home Office Overhead, Financial costs, Material and increased labor cost. Equation 2.1 shows the difference between and the original budgeted cost, which defines a change in cost.
From the equation (2.1), a model was constructed to determine the % increase in cost due to variation order. Equation (2.2) illustrates the impact of variation order on cost in industrial projects.
Serag and Oloufa, (2007), argued that 57% of changes increase the cost of the project. This increase is due to additions and deletions on the original designs and scope. However, most industrial projects, funds are put aside to deal with any possible change (Gransberg et al., 2006).
Variation order has an effect on time since it causes completion schedule delay. It is important to note the time when the change occurred when evaluating variation order regardless of the causes. Experienced project professionals consider this factor a significant factor when timing change. Change in time can be expressed in equation form as,
Delays are often brought about by changes in new equipment and material requirements. Delays in procurements may be experienced in industrial projects due to variations in material requirement (Al-Jishi and Al-Marzoug, 2008). The use of CPM analysis in determining general effects of variation order on project time is a useful method.
2.5 Managing variation Order
The occurrence of variation order causing bad performance of an industry can be controlled. The control of change order can be analyzed in three stages which include design-interface stage, design stage and the construction stage. Owners, contractors, and architect are responsible for variation order; therefore, the control of variation order must be in the stages influenced by these three parties. Owners may fail to understand the scope of the project while contractors might install nonconforming work that the owner accepts to avoid corrections (Atkins and Simpson, 2006). The architect may influence the variation orders due to omissions or disruptions when poor construction documents are prepared.
2.5.1 Construction Stage
There are several control tools which are to be taken into account in this variation order scope
The planners should have a well-developed scope so as to plan appropriately in order to reduce the negative impacts that are as a result of variation orders on both cost and time. When he scope is clearly stated, it is easy to distinguish between changes that are due to design development and change due o change in scope (Arain and Pheng, 2005).
- Involvement of the owner
The owner helps in approving the changes quickly and identifying noncompliance with the requirements hence it is necessary to involve him or her during the contraction phase. These will help in minimizing the impact of variation orders on cost and time in industrial projects.
- Use of management skills and project scheduling
Having a flexible schedule to manage variation order is necessary as well as dealing with the changes in a flexible manner. In industrial projects, PERT is a common technique used for scheduling. The schedule should show the impacts of variation order on time and cost at any given time.
- Written approvals
Before a change can be executed, the owner should approve in written form any changes in the work involving original price change. I someone else must sign for the owner, then it must be through an authorized procedure to allow ease in compensation claims. Verbal agreements should be avoided since it lacks legal proof (Von and Loch, 2004).
- Clarity of change order procedures
For effective management of change order, then the change order procedures should be clearly stated early in the project. These reduce processing time and saves on cost (Al-Dubaisi, 2000).
Other factors include: Change logic and justification, project manager from an independent firm to manage the project and avoidance of use of open tendering.
2.5.2 Design stage
During this phase several factors must be considered in rder to minimize the negative impacts of variation orders on cost and time. These factors are;
- Clear and thorough project brief
A clear plan identifies the objectives of the project hence helps reduce the occurrence of variation order through the reduction of noncompliance with requirements of the owner.
- Freezing design
Blocking the changes for changes after the design has been completed, helps to freeze the design in a method which is so strong reducing the numerous change orders and their impacts (Arain, 2005).
- Review of contract document
To ensure communication and co-ordination, contract documents should have balanced and comprehensive order change clauses.
- Thorough detailing design
Omissions and errors can only be identified in the project work to avoid variation order if the design is detailed.
- Involvement of professionals at the beginning of the project
When professionals are involved in the development of a project design, a more effective and compatible design is prepared which reduce the occurrences of variation order.
- Contractors involvement in planning and designing phase
The contractor should be allowed to give experienced suggestions at the early phase of the work so as to prevent occurrence of change order (Al-Momani, 2000).
2.5.3 Design-construction interphase stage
During the period between construction and design several tools should be taken care of at this stage. These control tools include;
- Ability to negotiate change
For effective management of variation order, the professional team should have effective negotiation skills such as communication skills and awareness of equipment’s, project detail and contract terms so as to reduce the negative impacts of variation order on cost and time in industrial projects.
- Co-ordination and of project professional team
This is an important factor in minimizing variation order since the contractor; the owner and the consultant combine efforts at the early phase of the project (Berends, 2000).
- Comprehensive site investigation
During the design stage, a comprehensive site investigation is important in identifying any uncovering site condition to avoid impacts of variation order on time and cost.
- Previous knowledge on similar projects
The past similar projects can help the professional team to formulate philosophies and strategies to avoid change orders.
The impact of variation order on industrial projects regarding cost and time can be quantified in an expert system Chao-ying (2005), but its functionality and effectiveness are limited due to lack of good data analysis techniques. A decision support system based on knowledge was put in place to manage variation orders. This system was designed to provide sufficient information and in accessible format to users (Yitmen et al., 2006).
(KBDSS) is a decision support system brought by Arian, 2005 to control variation order. The sufficient information provided by the KBDSS enables the users to make proper and useful decisions. The system has two major components which link six important stages, a control selection section and a knowledge-base to help in making correct and relevant decisions for change orders to be managed easily (Kerzner, 2013).
Data base Questionnaires
Interviews with professionals Data from different sources
Knowledge from literature
Knowledge found through Inference engine
Organization and initial sieving categorizing by types
Calculating cost implications
Knowledge base (KB) calculating frequency of
It has three parts variations
- Effects /control layer ( level 3) calculating percentages
Has suggested solutions and effects to a particular cause
- Micro layer (level 2)
Contains information of variation orders in a project
- Macro layer (level 1)
Contains information about past projects
User interface software interface
Import – export
User knowledge between KB and DSS
Decision support shell (DSS)
Through building the hierarchy among the main criterion
And the suggested controls, rating the controls and analyzing.
In this chapter am interested in creating a framework that binds my research together and analyses it in respect to the research question. As stated earlier where he basis of concern being the impact of change order on cost and time in industrial projects. The study have narrowed down to appropriate research and sampling designs, data collection tools and proper analysis techniques.
The following research design will be used in the study.
Survey research design using questionnaires
Survey design is suitable to determine the current impact of change order on cost and time as well as identifying the factors influencing change order. Survey is used to study large populations by selecting and examining the samples from a population to determine the distribution, relative incidence, and inter-relation of psychological and sociological variables. Questionnaires were given out to various respondents who were of interest in this study
The area of study that was covered in this research is Arabian construction company as it objectively aimed at pointing out specifically factors influencing change order in industrial projects managed by Arabian construction company. It was important to use the data from the Arabian construction company since the main problem was to establish main causes and impacts of change order in industrial projects in the gulf.
The primary target is the consultants involved in projects, managers in health departments, constructors of residential units, and professionals of industrial projects in the gulf.
The sampling design based on the composition of the target population is stratified random sampling as the population is heterogeneous. The population is from different sectors. Therefore, it is necessary to evaluate each sector separately to determine the effect of change order on the performance of each sector.
In considering the size of the sample to be studies, it is assumed to be greater than 10000, therefore the desired sample size will be derived from the following formula represented in equation (3.1),
Where from equation (3.1) we have:
– Desired sample size
– Proportion of population with a characteristic of interest
– Error margin (significant level)
Questionnaires were given out so as to obtain the sufficient data from the field. Questionnaires were used so as to avoid the bias which can be well evaded when questionnaires are used.
Questionnaires were administered to various personnel at Arabian construction company.
3.7.1 Contents of the questionnaires
The questionnaire has four sections. The first part has the respondents’ general information such as company size, contact address, type and characteristics of the industry like experience, amount of change and size. In te second section, the questions focus on the causes of change orders. The respondents are asked to state the frequency of occurrences of listed causes of change order in their projects. The respondents were expected to answer “very often” or “never”. To ease the analysis, the causes of change order were divided into three sub-groups which are; contractor originated causes, owner’s originated courses and design originated courses. The respondents were free to add more other causes of change order. The last two sections contained multiple choice questions where in section three the effects of change order on industrial projects were addressed while section four addressed control measures adopted to minimize the effects of change order on industrial performance. The ratings used were;
- Totally disagree = 1
- Partially disagree = 2
- Indifferent = 3
- Partially agree = 4
- Totally agree = 5
Questionnaires used in this study required information from different respondents such as engineers from consultant firms, clients, quantity surveyors, contractors and architects. Out of 200 questionnaires that were distributed, 170 of them were returned. The returned questionnaires represented the target population in the research. SPSS software program version 20 was used in the analyses of the dat. The table below shows the summarized responses in percentage.
Distribution and response of questionnaires
|Respondent||Questionnaire distributed||Questionnaire returned||Rate of responses|
3.8 Measuring Techniques
In the research, the direct impact on cost was studied where questions were in the questionnaires regarding the same.
There were questions in the questionnaires which required the respondent to provide the impact of time.
3.9.1 Statistical Analysis
In this analysis, data obtained from the questionnaires were analyzed to determine the impact of change order on time and cost. SPSS as a statistical package was employed to explore, summarize and analyzed the dataset.
Descriptive statistics, and mean ranks test was used to analyze the data that was obtained using the questionnaires. To obtain an index showing utilization of causes, effects and controls, scores were formulated as follows:
- Very Often = 100%
- Often = 75%
- Sometimes = 50%
- Seldom = 25%
- Never = 0%
These index are calculated as shown below
Number of people who answered (VERY OFTEN)
Number of people who answered (OFTEN)
Number of people who answered (SOMETIMES)
Number of people who answered (SELDOM)
Number of people who answered (NEVER)
3.9.2 Simulation Model Analysis
The probability distribution and calculation of impact of each factor were found using the simulation model. All the information obtained from the field was tabulated and percentage of change order calculated as in the equations below:
From the analysis, a simulation model was built based on the factors distributions tabulated below.
|Factors||Service time||Cost distribution function||Schedule distribution function|
|F1||0.49||TRIA (Max, Mode, Min)||WEIB (Beta, Alpha)|
|F2||0.3||NORM (Std Div, Mean)||EXPO (mean)|
|F3||0.9||UNIF (Max, Min)||Constant|
3.10 Building a Simulation Model
A simulation model was built using the data obtained by the questionnaires, interviews, and case studies. When the changes were input, the impact of change order on time and cost were shown clearly.
3.10 Model verification
The simulation model was verified using two methods,
- Method 1
Inserting the results of each case study on the model and comparing it by calculating the mean of the error through categorical regression test and bivariate correlations.
- Method 2
Reviewing with the supervisor the model systematically to ensure that there is no errors.
3.11 Model validation
The validity of the simulation model of change orders and their effects on time and cost was done through entering a new case on the model and later comparing the results and also through interviewing project professionals.
This chapter presents the results that were obtained after analyzing the data that was collected. The first section presents the descriptive statistics of the demographic information that was obtained. The second section presents the mean ranks of the factors causing change orders. The data that was analyzed was obtained using questionnaires, which were administered to different respondents from the Arabian construction company. 20 respondents returned the survey questionnaires and as such the data analysis is based on a sample of 20 respondents.
Below is the frequency table for the age of the respondents;
Table 1: Frequency table for age of respondents
|Frequency||Percent||Valid Percent||Cumulative Percent|
|Above 50 years||5||25.0||25.0||100.0|
It can be seen from the table above that the respondents who were of age 21-30 were 6, those between the ages 31-40 are 3, those between the ages 41-50 were 6 while those above the age of 50 years were 5.
Below is the frequency table for the marital status of the respondents:
Table 2: Frequency table for the marital status of the respondents
|Frequency||Percent||Valid Percent||Cumulative Percent|
From the table above, it can be seen that 7 respondents are single while 13 respondents are married.
Below is a frequency table for the role the respondents play in the construction industry.
Table 3: Frequency table for the role played in the construction industry
|Frequency||Percent||Valid Percent||Cumulative Percent|
It can be seen from the table above that 7 respondents were project engineers, 2 respondents were construction engineers while 4 respondents were contractors. Furthermore, there was one client and 6 consultants.
The table for mean rank test of the factors that cause the change of orders. The causes were ranked using a like art scale in which case 1 meant the least severe while 10 was the most severe factor that causes change of orders. From the means of these factors based on the respondents, all the means were more than 5 which implies that all the factors are severe factors causing change orders in industrial projects. Below are some of the factors that have a mean of more than 9 as can be seen from the table in the appendix.
- Effect of changes caused by consultant on time.
- Effect of customer request change in design on cost.
- Effect of construction contractors not involved in the original design on cost.
- Effect of construction contractors not involved in the original design on time.
- Effect of construction contractors not involved in the original design on success.
- Effect of market changes providing advanced materials and equipment on occurrences.
- Effect of bad quality shop drawings on success.
- Effect of reworks after contractor make several mistakes during construction on time.
- Effect of reworks after contractor make several mistakes during construction on success.
- Effect of bad material procurement approach and procedures on time.
- Effect of bad material procurement approach and procedures on success.
- Effect of wrong assumptions by owner and contractors on success.
- Effect of project size and contract type on time.
The study aimed at establishing the causes of change orders and their effects on cost and time. The uncertainties and risks that are associated with project changes makes prediction and planning for any changes in an industrial project a very difficult task. The study has established that the main source of change of orders is the changing of plan by the owners. The other source of change of orders is the change in mind in regard to materials which are always available. It is also worth to note that consultants also contribute to change of orders. Increase in the cost of a project and duration of the project are considered to be the main effects for change of orders.