Impact of Change Orders on Labor Efficiency for Electrical Construction

Change orders are a source of many disputes in today's construction industry. The issue at hand is whether or not the execution of change orders work has a negative impact on overall labor efficiency on a construction project. Previous literature demonstrates evidence that change orders affect labor efficiency. Attempts have been made to quantify these impacts by many researchers, with limited success. Using the electrical construction industry, a research study has been conducted to quantify the impacts of change orders on labor efficiency. In this paper, results of hypothesis testing and regression analysis are presented. A linear regression model that estimates the loss of efficiency, based on a number of independent variables, is also presented. The independent variables used in this model are (1) qualitative and quantitative criteria used to determine whether projects are impacted by changes or not; (2) the estimate of change order hours for the project as a percentage of the original estimate of work hours; (3) the estimate of change order hours for the project; and (4) the total number of years that the project manager had worked in the construction industry. Additional projects were used to validate the model, with an average error rate of 5%. The results of this research study are useful for owners, construction managers, general contractors, and electrical specialty contractors, because they provide a means to estimate the impact of a change order under certain project conditions. This research also identifies factors, which, when understood and effectively managed, may be used to mitigate the impact of a change order on project costs and efficiency.     

Impact of Change Orders on Small Labor-Intensive Projects

In today’s construction, small projects can be just as important if not more important than the larger projects. However, small projects are usually fast track projects, which often involve overlapping design and construction time. Subsequent modifications may be required for the sections that are already under construction. These disruptions to the ongoing project are labeled as change orders. The impact due to changes has been described as the adverse effect upon the unchanged work due to changes in the contract. For this study, 34 projects were selected to develop a statistical model that estimates the amount of labor efficiency lost due to change orders for small projects. The variables in the final model are percent design related changes, percent owner initiated changes, the ratio of actual peak labor to estimated peak labor, the ratio of actual project duration to estimated project duration, and project manager’s percent time on the project. The results of this paper are of value to owners, electrical and mechanical contractors, and construction managers. The model quantifies the impact of change orders by introducing the most important variables that bring the largest disruptions.     

Cumulative Effect of Project Changes for Electrical and Mechanical Construction

Change is inevitable on construction projects, primarily because of the uniqueness of each project and the limited resources of time and money that can be spent on planning, executing, and delivering the project. Change clauses, which authorize the owner to alter work performed by the contractor, are included in most construction contracts and provide a mechanism for equitable adjustment to the contract price and duration. Even so, owners and contractors do not always agree on the adjusted contract price or the time it will take to incorporate the change. What is needed is a method to quantify the impact that the adjustments required by the change will have on the changed and unchanged work. Owners and our legal system recognize that contractors have a right to an adjustment in contract price for owner changes, including the cost associated with materials, labor, lost profit, and increased overhead due to changes. However, the actions of a contractor can impact a project just as easily as those of an owner. A more complex issue is that of determining the cumulative impact that single or multiple change orders may have over the life of a project. This paper presents a method to quantify the cumulative impact on labor productivity for mechanical and electrical construction resulting from changes in the project. Statistical hypothesis testing and correlation analysis were made to identify factors that affect productivity loss resulting from change orders. A multiple regression model was developed to estimate the cumulative impact of change orders. The model includes six significant factors, namely: Percent change, change order processing time, overmanning, percentage of time the project manager spent on the project, percentage of the changes initiated by the owner, and whether the contractor tracks productivity or not. Sensitivity analysis was performed on the model to study the impact of one factor on the productivity loss (%delta). The model can be used proactively to determine the impacts that management decisions will have on the overall project productivity. They may also be used at the conclusion of the project as a dispute resolution tool. It should be noted that every project is unique, so these tools need to be applied with caution.     

Decision Tree Approach to Classify and Quantify Cumulative Impact of Change Orders on Productivity

Multiple or unusual change orders often cause productivity losses through a “ripple effect” or “cumulative impact” of changes. Many courts and administrative boards recognize that there is cumulative impact above and beyond the change itself. However, determination of the impact and its cost is difficult due to the interconnected nature of construction work and the difficulty in isolating causal factors and their effects. As a result, it is very difficult for owners and contractors to agree on equitable adjustments for the cumulative impact. What is needed is a reliable method (model) to identify and quantify the loss of productivity caused by the cumulative impact of change orders. A number of studies have attempted to quantify the impact of change orders on the project costs and schedule. Many of these attempted to develop regression models to quantify the loss. However, traditional regression analysis has shortcomings in dealing with highly correlated multivariable data. Moreover, regression analysis has shown limited success when dealing with many qualitative or noisy input factors. Classification and regression tree methods have the ability to deal with these complex multifactor modeling problems. This study develops decision tree models to classify and quantify the labor productivity losses that are caused by the cumulative impact of change orders for electrical and mechanical projects. The results show that decision tree models give significantly improved results for classification and quantification compared to traditional statistical methods in the field of construction productivity data analysis, which is characterized by noisiness and uncertainty.     

Model for Quantifying the Impact of Change Orders on Project Cost for U.S. Roadwork Construction

Change orders are very common in almost every construction project nowadays, often resulting in increases of 5–10% in the contract price. Understanding the consequences of such trends, several studies have attempted to quantify the impact of change orders on the project cost. Most of the studies aimed at the quantification of the change orders were sponsored by contractors’ organizations, where statistical models used to quantify the impact of the change orders on the project cost were based on data supplied by the contractors; a situation that can lead to owner-contractor disagreements related to the quantification method used. In addition, most of the studies tackled commercial and electromechanical work, and very rare studies tackled the field of heavy construction; a field that suffers from change orders because of errors and omissions, scope of work changes, or changes because of unforeseen conditions. This study addresses the need for a statistical model to quantify the increase of the contract price due to change orders in heavy construction projects in Florida. The model is based on data collected from 16 Florida DOT projects with contract values that ranged between $10–$25 million, and that encountered an increase in the contract price from 0.01 to 15%. Eleven variables were analyzed to test their impact on the cost of the change orders. The study concluded that most significant variables that impact the value of the change order, which are (1) the timing of the change order and (2) when the reason for issuing the change order is unforeseen conditions. Two regression models are developed and validated as follows: (1) a model to quantify the percentage increase in the contract price due to the change orders that increase the contract price from 0.01 to 5% and (2) a model to quantify the percentage increase in the contract price due to the change orders that increase the contract price from 5 to 15%. Those models will provide the owner with a retrospective or forward pricing of the change orders, and hence, allow the owner to estimate and utilize contingency amounts.     

Quantifying the Impact of Schedule Compression on Labor Productivity for Mechanical and Sheet Metal Contractor

In a typical construction project, a contractor may often find that the time originally allotted to perform the work has been severely reduced. The reduction of time available to complete a project is commonly known throughout the construction industry as schedule compression. Schedule compression negatively impacts labor productivity and consequently becomes a source of dispute between owners and contractors. This paper examines how schedule compression affects construction labor productivity and provides a model quantifying the impact of schedule compression on labor productivity based on data collected from 66 mechanical and 37 sheet metal projects across the United States. The model can be used in a proactive manner to reduce productivity losses by managing the factors affecting productivity under the situation of schedule compression. Another useful application of the model is its use as a litigation avoidance tool after the completion of a project.     

Owner’s Role in Construction Safety

Despite dramatic improvements in recent decades, the construction industry continues to be one of the industries with the poorest safety records. Recent improvements are due, in part, to the concerted efforts of owners, contractors, subcontractors, and designers. While past safety studies have investigated the roles of contractors, subcontractors, and designers, the owner’s impact on construction safety has not been previously investigated. This paper will present the results of a study on the owner’s role in construction safety. Data were obtained by conducting interviews on large construction projects. The relationship between project safety performance and the owner’s influence was examined, with particular focus on project characteristics, the selection of safe contractors, contractual safety requirements, and the owner’s participation in safety management during project execution. By identifying practices of owners that are associated with good project safety performances, guidance is provided on how owners directly impact safety performance.     

Structural Equation Model of Construction Contract Dispute Potential

This paper presents the results of a structural equation model (SEM) for describing and quantifying the fundamental factors that affect contract disputes between owners and contractors in the construction industry. Through this example, the potential impact of SEM analysis in construction engineering and management research is illustrated. The purpose of the specific model developed in this research is to explain how and why contract related construction problems occur. This study builds upon earlier work, which developed a disputes potential index, and the likelihood of construction disputes was modeled using logistic regression. In this earlier study, questionnaires were completed on 159 construction projects, which measured both qualitative and quantitative aspects of contract disputes, management ability, financial planning, risk allocation, and project scope definition for both owners and contractors. The SEM approach offers several advantages over the previously employed logistic regression methodology. The final set of structural equations provides insight into the interaction of the variables that was not apparent in the original logistic regression modeling methodology.     

Effects of Delivery Systems on Change Order Size and Frequency in Mechanical Construction

Change orders represent one of the largest sources of cost growth on building construction projects. Field generated, or “unforeseen” change orders can also be highly disruptive to field productivity. Design-build delivery methods can potentially help minimize change orders on construction projects. This study was performed to closely examine the effects of delivery methods on the frequency and magnitude of change orders in mechanical construction, and how design-build business practices can be used to minimize the frequency of field generated chance orders. In a study of 598 change orders occurring on 120 construction projects performed by the same contractor, the total number of change orders was found to be close to the same on design-build and design-bid-build projects, however an 87% decrease in the average number of unforeseen change orders was observed on design-build projects versus design-bid-build projects. In addition, the average size of unforeseen change orders was 86% smaller on design-build projects. A detailed and qualified presentation of the research methodology and resulting data is provided. Key attributes and business practices leading to the results are discussed and practical applications of this research for owners and contractors are provided.     

Impact of Green Building Design and Construction on Worker Safety and Health

Sustainable, or “green,” rating systems, such as the United States Green Building Council’s Leadership in Energy and Environmental Design (LEED), are leading to changes in the way owners, designers, and contractors approach the design, construction, and operation of buildings. The processes and features included in green design and construction may have positive and/or negative impacts on construction worker safety and health. This paper presents the findings of a research study of the impact of green building design and construction practices on construction worker safety and health. Occupational Safety and Health Administration (OSHA) recordable and lost time injury and illness data from green projects (as identified by LEED) and from nongreen projects was collected through a structured questionnaire survey. The data collected was analyzed to test for the presence of a difference in OSHA recordable incident rates (RIRs) and lost time case rates (LTCRs) between green and nongreen projects. It was found that there was suggestive, but inconclusive evidence of a statistically significant difference in the RIRs of the green and nongreen building projects included in the study. No statistically significant difference was found between the LTCRs for the green and nongreen projects included in the study. The study findings provide valuable information to the construction industry for the purposes of project safety planning and the assessment of safety and health on projects.     

Role of Workforce Management in Bridge Superstructure Labor Productivity

There have been many studies on different aspects of the construction process in regard to how they each impact construction productivity. In reviewing the documentation of this research, very few articles were located that dealt with heavy/highway construction in general, and even fewer were found that dealt with bridges in particular. In addition, very little was found in the literature dealing with the effect that the quality of workforce management has on construction productivity. This paper describes the results of four case studies of highway bridge construction performed by established contractors with little bridge building experience, in which workforce management had a significant negative effect on labor productivity. The contractors’ lack of experience in bridge construction seemed to be the cause of several problems that plagued each of the four projects. The baseline productivity of each project was calculated, and the loss of labor efficiency was estimated to be 80, 75, 32, and 70%, respectively. The schedule slippage on the four case study projects was estimated to be between 127 and 329%.     

Arbitral Tribunal Proceedings Case Study: Egyptian Large-Scale Construction Project

This paper investigates how arbitration is used as a dispute resolution mechanism in Egyptian large scale construction projects and what are the types of issues that construction professionals should address when they encounter claims in the Egyptian construction market. To meet the goals and objectives of this study, a research project was conducted to study the arbitration process for a dispute that was in excess of $31 million, which arose out as a result of the proceeds of a large-scale project with an original contact price of $85 million that was constructed in Cairo, Egypt. This research project analytically investigated the background of the conflicts, the arbitral proceedings, and the award issued by the arbitral tribunal. Based on such thorough study, it was concluded that arbitration did not provide a timely and cost-effective resolution for the said dispute. Moreover, the same study has raised questions in relation to the overall management of megaconstruction projects in Egypt namely: (1) the impartiality of project managers; (2) the magnitude of change orders and consequent delays; (3) the magnitude of claimed amounts; and (4) the level of management and administration of claims and disputes. It is perceived that this paper would trigger professionals to think of other suitable dispute resolution mechanisms, such as dispute review boards, for settlement of claims arising from Egyptian large scale construction projects. Furthermore, this study would be of value for contractors and owners who intend to work in the Egyptian construction market.     

Contractor’s Opportunistic Bidding Behavior and Equilibrium Price Level in the Construction Market

The competitive bidding system has been to blame for abnormally low bids, which are considered as one of the main causes of poor project quality. Previous studies have regarded the pricing of bidders as an optimum decision based on contractor’s cost and market competition level. However, the sell to produce characteristic of construction projects may induce contractors to offer a low bid and then make up the amount initially sacrificed from beyond-contractual reward (BCR) gained through cutting corners and claims. System dynamics was adopted in this study to develop a contractor’s pricing model with consideration of the dimensions of cost, market competition, and BCR. The model was then examined by statistical analysis of data collected from 44 highway projects in Taiwan. It was found that the equilibrium market price is significantly associated with BCR, which is assumed to be determined by the strictness of the owner’s construction management, including both soundness of contract and tightness in construction supervision. Research results suggest that contractors divide the market into different segments according to the owner’s strictness of construction management and the equilibrium price level of each market segment varies. The price level for projects with a strict owner is remarkably higher than for those with relatively less strict owners. Improvement in the construction management system of projects is crucial to lower the possibility that contractors gain BCR and do opportunistic bidding, and to further enhance project quality.     

Quantitative Definition of Projects Impacted by Change Orders

Change, defined as any event that results in a modification of the original scope, execution time, or cost of work, is inevitable on most construction projects due to the uniqueness of each project and the limited resources of time and money available for planning. Change may occur on a project for a number of reasons, such as design errors, design changes, additions to the scope, or unknown conditions. For each change, contractors are entitled to an equitable adjustment to the base contract price and schedule for all productivity impacts associated with the change. Changes may or may not have an impact on labor productivity. Existing literature uses subjective evaluation to determine whether the project is impacted. Projects impacted by change cause the contractor to achieve a lower productivity level than planned. The focus of this paper is to quantify whether an electrical or mechanical project is impacted by a change order. Through statistical hypothesis testing, groups of factors that correlate with whether a project is impacted by change orders were identified and used to develop a quantitative definition of impact. Logistic regression techniques were used to develop models that predict the probability of a project being impacted. The results of this research show that percent change, type of trade, estimated and actual peak manpower, processing time of change, overtime, overmanning, and percent change related to design issues are the main factors contributing to the project impact.     

Quantitative Impacts of Project Change: Size Issues

Change has a tremendous effect on the performance of a construction project. Research that focuses on the quantitative impact is limited, incomplete, and in some cases questionable. The goals of this study were to quantify the nature and impacts of project change and develop recommended practices so that owners and contractors can manage change better. The focus was on project change during detailed design and construction, in particular the size of change and its impact on the project. These results show that the amount of change is negatively correlated with productivity and total installed project cost, whether within the design phase or construction phase, or between them. The greater the amount of change the more productivity and costs are degraded. Recommendations are also offered here on how to mitigate the impact of project change.     

Change Orders Impact on Labor Productivity

This paper describes a study conducted to investigate the impact of change orders on construction productivity and introduces a new neural network model for quantifying this impact. The study is based on a comprehensive literature review and a field investigation of projects constructed in Canada and the USA. The field investigation was carried out over a 6-month period and encompassed 33 actual cases of work packages and contracts. Factors contributing to the adverse effects of change orders on labor productivity are identified and a model presented earlier is expanded to account primarily for the timing of change orders, among other factors. The developed model, as well as four models developed by others, have been incorporated in a prototype software system to estimate the loss of labor productivity due to change orders. A numerical example is presented to demonstrate the use of the developed model, and illustrate its capabilities.     

Partnering: Why Project Owner-Contractor Relationships Change

Over the last decade, research in the construction industry has explored the owner-contractor relationship in project management resulting in a different paradigm called partnering. Partnering is a relationship characterized by cooperation and collaboration in contrast to the adversarial relationship more commonly experienced between owners and contractors. This study utilized data collected from 276 construction projects to examine the stability in the owner-contractor relationship. Owner-contractor relationships were classified as being adversarial, guarded adversarial, informal partners, or project partners. Fifty-eight percent of the projects experienced some fundamental change in working relationship—either positive or negative. Projects that began as formal partnerships were the most stable with over two thirds ending as they began. Guarded adversarial was the least stable with fewer than 30% maintaining this kind of relationship at the end of the project. Content analysis of the reasons stated for the change revealed factors that contribute to an improvement or deterioration in working relationships. The writers use this analysis to make recommendations for sustaining and improving partnerships between owner and contractors.     

Economic Value of Combined Best Practice Use

This paper measures the value of best practices based on data taken from the Construction Industry Institute Benchmarking and Metrics database. A three-step process provides the basis for measuring the potential benefits of increased best practice use. First, a practice use index is derived to model the way in which best practices are utilized on actual projects. The index combines data from eight best practices to create a single measure of practice utilization. Second, a project performance index, combining cost and schedule metrics, is derived as an indicator of overall project performance. Third, the practice use index is correlated with cost, schedule, and overall project performance metrics. Both owners and contractors benefit from increased practice use. Potential cost savings for owners range from $1.7 to $3.4 million, depending on industry group and project size. Potential cost savings for contractors are higher, averaging $7.2 million for the typical $88 million heavy industrial project. Benefits from schedule reductions are most apparent for owners. On large building projects, schedule reductions for owners average 27 weeks. Finally, improvements in overall project performance on the order of 30% are observed for both owners and contractors.     

Union and Open Shop Labor Cost Differences

One area within the construction industry that has dramatically changed is the growth of open shop construction. This growth suggests that open shop general contractors may have a competitive advantage over union general contractors. This paper investigates productivity and wage rate variances between Colorado open shop and union general contractors on projects completed since January 1981. Though there is little productivity variance, a significant variance of wage rates indicate the Colorado open shop general contractor presently has a clear overall labor advantage. The productivity and wage rate variance of 29 individual project job tasks were investigated. Data was collected from 35 union and 20 open shop contractors' project labor costs reports. Additional information was collected during interviews with representatives of eleven general contractors. The productivity and wage rate variances are described by individual job tasks; by the union craft jurisdictions of laborers, carpenters, ironworkers, and cement finishers; and by an overall comparison between open shop and union general contractors.