Conceptual Planning Process for Electrical Construction

The competitive nature of the construction industry has motivated many specialty contractors to search for ways to improve efficiency by increasing their quality and decreasing their costs in order to strengthen their market share. As a result, contractors are turning to “better planning” as a method for improving their efficiency and, consequently, increasing their profitability. In fact, a consensus exists in the construction industry that more formalized preconstruction planning is necessary to remain successful in an increasingly competitive industry. This paper presents a model electrical preconstruction planning process that was crafted from outstanding processes used on several successful electrical projects. Furthermore, a method to evaluate the effectiveness of planning, by comparing actual planning to the model process, is briefly introduced. From this assessment, “effective planning” was correlated to project outcome, and evidence is provided that better planning is, indeed, related to successful performance.     

Impact of Overmanning on Mechanical and Sheet Metal Labor Productivity

This paper details the impacts of overmanning on labor productivity for labor-intensive trades, namely mechanical and sheet metal contractors. Overmanning, as used in the following research, is defined as an increase of the peak number of workers of the same trade over the actual average manpower used throughout the project. The paper begins by reviewing literature on the effects of overmanning on labor productivity. Via a survey to various contractors, data were collected from 54 mechanical and sheet metal projects located across the United States. Various statistical analysis techniques are then performed to determine quantitative relationship between overmanning and labor productivity. These techniques include the stepwise method, T-test, P-value tests, analysis of variance, and multiple regression analysis. The results indicate a 0–41% loss of productivity depending on the level of overmanning and the peak project manpower. Cross-validation is performed to validate the final model. Finally, a case study is provided to demonstrate the application of the model.     

Contractor Process Improvement for Enhancing Construction Productivity

This paper presents a regression model that relates job site productivity to process improvement initiatives (PIIs) executed both before and during construction. Applied during early project stages, this model helps industry practitioners to predict the expected value of labor productivity based on certain inputs related to preconstruction planning and construction execution. The model demonstrates the strong relationship of project performance to a variety of PIIs including design completeness, definition of a project vision statement, testing oversight, and project manager experience and dedication. The correlational research methodology targeted 75 projects representing approximately $274.53 million in civil construction. The data collection effort considered 45 PIIs (independent variables) using quantitative and qualitative measures. The modeling technique involved the use of multiple linear regression, a method that exploits available data from multiple, independent sources to focus on specific outcomes. The model was developed directly from contractor specific information and subjected to rigorous statistical analysis. The model provides project managers as front line industry practitioners with a deliberate yet practical approach to project management and productivity enhancement. The modeling results include verification analysis and a discussion of the model’s usefulness and limitations.     

Construction Planning Method Using Case-Based Reasoning (CONPLA-CBR)

During the construction process, there occur many unexpected events that hinder timely completion of a project. One plausible solution in formulating a robust plan against such uncertainties is to provide the proper construction duration by utilizing as-built schedules in which past events are stored for similar future projects. Many schedulers thus develop schedules based on similar past schedules, taking into consideration the dynamic construction environment. As a result, construction schedulers normally refer to similar past schedules for their current projects. Few studies on the reuse of past schedules using case-based reasoning (CBR) have been conducted, and those that are available are limited to specific areas of construction such as apartment-building construction and boiler manufacturing. This research has an emphasis on developing a CBR-based general planning tool with higher applicability, which consists of generic attributes with the capability to be customized to the given project. To address this issue, construction planning by CBR (CONPLA-CBR) is presented as a generic planning tool for various types of construction projects. CONPLA-CBR, with the dynamic case approach and construction schedule data mart, also developed in this research, helps schedulers to utilize past schedules. CONPLA-CBR was not only verified to be of practical utility by experts, but also, because it uses past cases to which the successor relationships pertain, it does not require users to input all relationships. Whereas the proposed CONPLA-CBR generates master schedules at the preconstruction stage, its concept can also be applied to the construction stages to generate more detailed, for example, weekly or monthly, schedules. Thereby, CONPLA-CBR would enhance construction performance through the increased application of CBR in construction.     

Duties and Responsibilities of Construction Managers: Perceptions of Parties Involved in Construction

This paper reports the findings of a study conducted by researchers at Illinois Institute of Technology under the direction and supervision of the ASCE Committee on Management Practices in Construction to investigate the expectations of the parties involved in the construction process, including designers, owners, general contractors, subcontractors, construction managers, and educators, relative to construction managers’ duties. The findings suggest that while there is some consensus among parties to a construction project relative to CM duties particularly in the construction phase, there is also some disagreement, most of which appear to be between contractors and designers. Most disagreements are related to CM duties performed in the bidding and postconstruction phases of projects.     

Sequence Planning for Electrical Construction

The sequences in which work is completed bear significantly on the performance of electrical contractors in building construction projects. When project work sequences are poorly planned or poorly executed, electrician constructors often must contend with compressed schedules, trade stacking, and out-of-sequence work to ensure timely completion of a project. This paper analytically evaluates the importance of sequence planning to efficient electrical work. It describes changes that were made to crew-level planning procedures for an electrical contractor and the impact these had on crew performance. The analysis shows that sequence planning at both the project level and the crew level are important to the performance of electrical crews. Most notably, a strong correlation (0.73) was detected between crew planning performance one week and crew productivity performance in the following week. Results of the study are provided. Principles of sound sequences and guidelines for sequence planning are also captured from the analysis. These sequence guidelines are designed to avoid, where possible, the often adverse project conditions in which electrical contractors find themselves and to handle those conditions most effectively when they cannot be avoided.     

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.     

Integrating Construction Process Documentation into Building Information Modeling

The research described in this paper extends the use of building information modeling (BIM) throughout the construction phase of the project life cycle. The owner is a military base that uses three-dimensional (3D) modeling for underground services and the footprints of the buildings. They were interested in determining the feasibility of capturing the construction process and related documents into a similar format. The research was conducted in parallel with traditional methods. The objectives of this project were to create a 3D as-built model, a four-dimensional as-built model, and attach the construction process information to the model for the owner to use after construction. A literature review indicates that BIM application stops at the preconstruction phase with a limited amount of research regarding data collection of the construction process. Significant contributions include practical 3D data collection methods and extending the BIM software products to accommodate construction process documentation. Results indicate that BIM software is not specifically prepared to accomplish these objectives and some modification to procedures as well as software were necessary for the BIM to capture the construction process documentation.     

Stimulating Construction Innovation in Singapore through the National System of Innovation

This paper examines the national approach to the stimulation of innovation in construction. Based on a qualitative systems thinking approach, a model of the National System of Innovation (NSI) is structured with five main NSI actors: local contractors; suppliers; national research institutions; government; and foreign contractors. This model, established by the assumption that local contractors’ key motivation for innovation is based on profit maximization, highlights two main driving forces of construction innovation within the NSI: profit incentives and the social desirability of higher construction productivity and quality. The research findings indicate that high profit levels provide a higher number of growth momentums compared to the social desirability of innovation. Additionally, although social desirability of construction innovation is associated with a number of obstacles, high profit levels do not impose any significant hindrances. Based on the research findings, it is concluded that innovation policies should be focused on sustaining higher profit levels of contractors. The social desirability of innovation can be more efficiently utilized by regular reviews of national policies as the industry develops.     

Finance-Based Scheduling: Tool to Maximize Project Profit Using Improved Genetic Algorithms

Contractor’s ability to procure cash to carry out construction operations represents a crucial factor to run profitable business. Bank overdrafts have always been the major source to finance construction projects. However, it is not uncommon that bankers set a limit on the credit allocated to an established overdraft. Bankers’ interest rates and consequently contractors’ financing costs are basically determined based on the allocated credit limits. Furthermore, project indirect costs are directly proportional to the project duration which is affected by the allocated credit limit. Thus, the credit limit affects project financing costs and indirect costs which in turn affect project profit. However, finance-based scheduling produces financially executable schedules at specified credit limits while maintaining the demand of time minimization. Thus, finance-based scheduling provides a tool to control the credit requirements. This control enables contractors to negotiate lower interest rates which reduce financing costs. Thus, finance-based scheduling enables contractors to reduce project indirect costs and financing costs. This paper utilizes genetic algorithm’s technique to devise finance-based schedules that maximize project profit through minimizing financing costs and indirect costs.     

Model for Predicting the Performance of Project Managers at the Construction Phase of Mass House Building Projects

The need to match project managers’ (PMs) performance measures onto projects of both unique and similar characteristics has long since been acknowledged by researchers. The need for these measures to reflect the various phases of the project life cycle has also been contended in the recent past. Here, a competency-based multidimensional conceptual model is proposed for mass house building projects (MHBPs). The model reflects both performance behaviors and outcome in predicting the PMs’ performances at the conceptual, planning, design, tender, construction, and operational phases of the project life cycle. Adopting a positivist approach, data elicited for the construction phase is analyzed using multiple regression techniques (stepwise selection). Out of a broad range of behavioral metrics identified as the independent variables, the findings suggest the best predictors of PMs’ performances in MHBPs at the construction phase are: job knowledge in site layout techniques for repetitive construction works; dedication in helping works contractors achieve works schedule; job knowledge of appropriate technology transfer for repetitive construction works; effective time management practices on house units; ability to provide effective solution to conflicts, simultaneously maintaining good relationships; ease with which works contractors are able to approach the PM and volunteering to help works contractors solve personal problems. ANOVA, multicollineriality, Durbin–Watson, and residual analysis, confirm the goodness of fit. Validation of the model also reflected reasonably high predictive accuracy suggesting the findings could be generalized. These results indicate that the model can be a reliable tool for predicting the performance of PMs in MHBPs.     

Impacts of Overseas Management Structures on Project Buyout Management: Case Studies of Chinese International Contractors

Project buyout management is essential for the transition from the preconstruction to the construction phase. It is during this period that the project team is formed; subcontractors are finalized; the orders of material and equipment are placed; and project plans are made. Despite its importance, few studies have been conducted in this field, especially for international contractors who face many complex situations in project buyout. This paper presents the study conducted for the project buyout management for the Chinese International Contractors (CICs) in developing countries, with focus on the project buyout management under different overseas management structures, and the key influencing factors. It discusses the characteristics of CICs in developing countries; investigates the project buyout management under different overseas management structures; analyzes the advantages and disadvantages of each overseas management structure to project buyout, and identifies the major project buyout influencing factors. The results of this research will benefit both the industry practitioners and the academic researchers in this area.     

Statistical Analysis on the Cost and Duration of Public Building Projects

A probabilistic model is proposed to predict the risk effects on time and cost of public building projects. The research goal is to utilize a real history data in estimating project cost and duration. The model results can be used to adjust floats and budgets of the planning schedule before project commencement. Statistical regression models and sample tests are developed using real data of 113 public projects. The model outputs can be used by project managers in the planning phase to validate the schedule critical path time and project budget. The comparison of means analysis for project cost and time performance indicated that the sample projects tend to finish over budget and almost on schedule. Regression models were developed to model project cost and time. The regression analysis showed that the project budgeted cost and planned project duration provide a good basis for estimating the cost and duration. The regression model results were validated by estimating the prediction error in percent and through conducting out-of-sample tests. In conclusion, the models were validated at a probability of 95%, at which the proposed models predict the project cost and duration at an error margin of ±0.035% of the actual cost and time.     

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.     

Accuracy of Highway Contractor’s Schedules

Contractors are required by the Michigan Department of Transportation (MDOT) to submit a progress schedule identifying the controlling path of activities for a construction project. During the 2000 construction season, MDOT allowed contractors to submit a progress schedule with overlapping or concurrent controlling operations. Prior to this, only one activity at a time could be controlling on the progress schedule. This paper reports on the results of a research project where the focus was to examine the accuracy of the progress schedules, which only list controlling items. Eight construction projects were studied and a determination of progress schedule accuracy was made. This was done to determine if there was an increase in accuracy of the schedules when concurrent controlling operations were used. Included in the eight projects were four without concurrent controlling activities and four with concurrent controlling activities. A comparison based upon similar projects with and without concurrent activities was made. Additionally, 22 projects were analyzed, all without concurrent controlling activities, to determine the accuracy of progress schedules for two types of projects. The comparison revealed that, in three of the four cases, the accuracy of progress schedules increased with the allowance of concurrent controlling activities. The 22 projects revealed that the accuracy of progress schedules varied considerably. It was also determined that contractors overestimated the duration of activities included in progress schedules.     

Contemporary Design-Bid-Build Model

Empirical research was performed into the hypothesis that a substantial number of building performance engineering tasks on design-bid-build projects are typically provided by entities associated with the construction phase, not with the architect-engineer (AE) of record. This hypothesis is contrary to the traditional understanding of design-bid-build and is theorized to result from increased time pressures on AEs, decreased AE profit margins, AEs’ attempts to minimize liability, increased design and construction specialization, and increased prefabrication. Project technical specifications were analyzed for 20 $5–45M building construction projects and 16 individuals directly associated with these projects were interviewed. It was found that 35 building performance engineering tasks were required by the project specifications to be performed by entities associated with the construction of the buildings. This large number of delegated design tasks suggests the conventional understanding of the design-bid-build process is not accurate. The increasing fragmentation of the design and construction process may have implications for the efficiency of communication on design-bid-build projects, lean construction processes, and constructability.     

Analysis of the United States Department of Transportation Prompt Pay Provisions

In recent past the United States Department of Transportation has implemented a number of changes in regulations regarding federal-aid transportation projects. Some of these regulations are designed to help the disadvantaged business enterprise (DBE) firms and subcontractors in general, by requiring the general contractors to pay their subcontractors in a timely manner. Further, these regulations require that general contractors pay their subcontractors’ retainage after the subcontracts are completed, even if they have not received their own retainage from the owner. This paper reviews these new regulations and introduces a financial model for quantifying the effect of these new regulations on the contractors’ profit and the cost of transportation projects. The analysis is done using a spreadsheet-based cash flow model that takes into consideration the expenditure curve, the owner and general contractor’s payment and retainage policies, front money, finance charge on negative cash flow, and interest income on positive cash flow, and final payment and return of retainage policies. A survey was conducted among contractors in Massachusetts and their input was used to run the cash flow model. The results of the analysis for eight different projects are presented and it is shown that the new regulations, on average, reduced the contractor’s profit by 4.35%. It is also shown that the average potential cost increase for transportation projects is 0.14%.     

Avoiding and Mitigating Delay and Disruption Claims Conflict: Role of Precontract Negotiation

Delay and disruption claims often generate conflict and contract dispute in the delivery of building and civil engineering projects. If construction delay claims conflict can be avoided or mitigated, there could be substantial financial savings on projects. This study explores the effect of precontract negotiation as a means of avoiding or mitigating delay and disruption claims conflict. The data collection instrument was a structured questionnaire administered face to face on 41 contractors’ personnel on 41 completed projects in Singapore. The data were analyzed using structural modeling with partial least squares estimation approach. The results indicate that when the contractors received an unfavorable outcome from the contract administrator’s decision on their claims for delay, the intensity of conflict was lower when there was precontract negotiation and precontract agreement regarding the rules for quantifying and assessing the impact of anticipated delays than when there was none. It was also discovered that the higher the level of precontract negotiation and precontract agreement on the rules for quantifying and assessing delays, the higher the contractors perceived the quality of the decision-making process for delay claims during the construction phase. Further, the higher the contractors perceived the quality of the decision-making process for delay claims, the lower the intensity of conflict. At the time of entering into contracts, owners and their project management team need to pay more attention to precontract negotiation and agreement with their contractor to clarify and agree on the rules for quantifying and assessing the impact of anticipated delay and disruption. Aspects that require precontract negotiation, agreement, and clarification include: the rules of evidence for claims, the record requirements for claims and the procedure for keeping the records, form of construction program including the software for the preparation of the program and the procedure updating the program, the methodology for analyzing delay claims, formula for quantifying unabsorbed head office overhead component of prolongation cost, the method for quantifying disruption cost, the handling of concurrent delays, profit—whether claimable and the rate of profit to be paid, acceleration—circumstances under which it will be compensated and basis of compensation, and the question of who owns the float. These are, typically, not adequately covered by most standard forms of contracts. The agreements on these matters may be incorporated as part of partnering agreement or as a supplement to the contract agreement. Precontract negotiation, clarity, and agreements could produce instrumental and noninstrumental (social psychological) effects, which could facilitate delay and disruption claims assessment and their resolution. It could mitigate conflict even when the outcomes are unfavorable to a party.     

Can Design Improve Construction Safety?: Assessing the Impact of a Collaborative Safety-in-Design Process

This paper analyzes the impact of a large-scale safety-in-design initiative during the design and construction of a semiconductor manufacturing facility in the Pacific Northwest of the United States. Drawing on multiple data sources including individual interviews, group interviews, construction documentation, and an expert panel involved in the initiative, the writers identify 26 potential design changes on the project and assess the importance of timing, trade contractor involvement, and the type of design change in determining whether a proposed design change was ultimately integrated into the final construction plans. The writers further consider whether adopted design changes would have occurred in the absence of the safety-in-design initiative and whether the accepted design changes ultimately impacted construction site safety on the project. This analysis of a full-scale safety-in-design initiative provides important insights into how injury prevention efforts in the construction industry can begin upstream by involving designers, engineers, and trade contractors in preconstruction processes.