Thesis (M.S.)--Worcester Polytechnic Institute. / Keywords: Change orders; Change orders due to errors & omissions; 3D parametric building modeling; CAD systems; Project design coordination; Design documents. Includes bibliographical references (p. 99-102).

Change orders occur frequently in most construction projects, where contract modifications that increase the contract value between 5 to 10% are expected. Changes occur not only because of errors and omissions, but also for other reasons such as scope of work changes, or changes because of unforeseen conditions encountered on the site; a problem which is very common in most heavy construction projects. Changes themselves might not cause productivity losses; in this case the damage calculation will be straightforward. However, changes may cause disruption in unchanged work where the working conditions are impacted, and as a result, lost productivity (inefficiency) is encountered. Delay and loss of productivity are the two main types of damages experienced by the contractor when the owner issues a change order. Courts have recognized Critical Path Method (CPM) schedule analysis as the preferred method of identifying and quantifying critical delays. As for the inefficiency damages, there is no way of directly measuring inefficiency due to its qualitative nature and the difficulty of linking the cause of the productivity loss to the damage. Most of the scholarly work published in this area was based on productivity data supplied by the contractors. The owner's viewpoint was seldom considered; and that explains why there are discrepancies between what the contractor asks for and what the owner believes the contractor is entitled. This research focuses on analyzing the change orders and the productivity loss from public owner data. The study addresses the need for a statistical model to quantify the change orders and the productivity loss from verifiable owner's data such as owner's daily reports, change orders, drawing, and specifications, rather than rely on contractor surveys. Two models are developed and validated; the first model is to quantify the percent increase in the contract price due to the change orders. This model will provide the owner with an estimate of the cost of the changed work, where it can be used for forward pricing or retrospective pricing of the change orders. The second is to quantify the productivity loss of the piping work due to the change orders. The productivity loss study analyzed two set of data; the first included all the predictor variables which both parties, the owner and the contractor, contributed to the productivity loss, and the second one included the predictor variables, from the legal view point, only the owner is responsible for. The study showed the difference between what the contractor asked for and what he is actually entitled. This model can be used by both the owner and the contractor to quantify the productivity loss due to change orders.

Yes / The cost performance of a wide range of public sector infrastructure projects completed by a contractor are analysed and discussed. Change-orders after a contract to construct an asset was signed were, on average, found to contribute to a 23.75% increase in project costs. A positive association between an increase in change orders and the contractor’s margin were identified. Taxpayers pay for this additional cost, while those charged with constructing assets are rewarded with an increase in their margins. As the public sector embraces an era of digitisation, there is a need to improve the integration of design and construction activities and engender collaboration to ensure assets can be delivered cost effectively and future-proofed. The research paper provides empirical evidence for the public sector to re-consider the processes that are used to deliver their infrastructure assets so as to reduce the propensity for cost overruns and enable future-proofing to occur.

Design changes during construction, which are typical in most projects, lead to increased cost, loss of productivity and delays. These changes are usually due to approved scope changes or due to design errors and omissions (E&Os) found in the construction documents. Errors and omissions are typically manifested in terms of incorrect or inconsistent dimensions and layouts in the construction documents, or by the lack of timely and correct information that it is needed to build the project or to meet the code requirements. Among others, E&Os are usually caused by poor coordination and communication among the many parties involved in the design process. The objective of this research is to explore the extent to which change orders resulting from errors and omissions in the design documents are caused by poor coordination and communications, and to determine the extent to which the use of the concept of the 3D parametric building model can be used to minimize or eliminate E&Os, hence minimizes total change orders. The concept of the 3D parametric building model has been implemented in commercial software using object-oriented technology. It creates a centralized database storing all the information about the design components as well as their interrelationships. Thus, whatever change is made is consistently propagated to the entire design object. The research was conducted through reviewing of the literature, a case study and a web-based survey among design professionals. The study revealed that 35% of E&Os are primarily due to poor coordination and that the use of 3D parametric building model has a significant impact on productivity and on improving the coordination of the design process. This model shows promising results in helping to minimize errors and omissions in the design documents.

Although change orders occur on many construction projects, data examined in this paper suggest that many change orders can be avoided on roadway construction projects through improved project planning and scoping. Statistical analyses of change orders on 610 Kentucky roadway construction projects from 2005-2008 examined how the causes of change orders varied between construction versus maintenance projects, different road types (e.g., state highways, interstate, and county roads), and construction type (e.g., earth work, structures, and road surfacing). The research examined the risk posed by engineering change orders by measuring the frequency and average percentage change in project costs for different types of change orders. Although the relative impacts did vary by analyses, the leading causes of change orders within the state consistently included contract omissions, owner-induced enhancements, and contract item overrun. The paper's primary contribution to the overall body of knowledge is the establishment of evidence that many high risk change orders on roadway construction projects can be avoided through improved front end planning, whereas avoidance of other change orders, such as fuel and asphalt price adjustments, are more challenging because they can be caused by rapidly changing market conditions. The results show not only distinctive trends that are useful for constructability reviews on future projects, but also identify the need for new directions in front end planning and project scoping to minimize change orders on highway projects.

Världen över sker ständiga budgetöverskridanden. Offentliga verksamheter har inte varit något undantag för dessa kostnadsöverskridanden, vilket skapar incitament till att förstå varför de uppstår. I de offentliga projekten drabbas fler än bara de projektansvariga vid budgetöverskridelser. Det är samhället i stort som får betala för arbetet eftersom det är skattefinansierade projekt. Examensarbetet utgör en fallstudie som genomfördes med syftet att skapa förståelse för varför budgetöverskridanden sker i en liten kommun. För att uppnå syftet har både sekundär- och primärdata använts i form av en djupgående dokumentanalys vilken kompletterats av intervjuer. Som fallstudieobjekt har en liten kommun använts för att samla in material. Arbetets dokumentanalys syftar till att sammanställa och jämföra tidigare utförda projekt. Intervjuer med respondenter har kompletterat och förklarat de budgetavvikelser som uppmärksammats från dokumentanalysen. En litteraturstudie av tidigare forskningens resultat möjliggjorde även för jämförelse och ökad förståelse av resultatet. Resultatet av studien är en förklaring till varför budgetöverskridanden förekommer i en liten kommun. De huvudsakliga anledningarna är ändrings-, tilläggs- och avgående arbeten (ÄTA-arbeten) i projekten vilket orsakas av olika faktorer. Dessa olika faktorer kan vara exempelvis felaktiga handlingar eller dåliga markförhållanden. ÄTA-arbeten är väldigt kostnads- och tidsdrivande vilket orsakar budgetöverskridanden. Studien visar också att kostnadsöverskridanden är mer vanligt förekommande än tidsöverskridanden / All over the world budget overruns occur. Public organisations have been no exception for these overruns, which incentivizes creating an understanding to why they occur in the first place. In the public projects there are more people than just the project managers who are affected by these overruns. This is due to the fact that the public projects are financed by tax funds which is paid by the society as a whole. The purpose of this study is to create an understanding of why budget overruns occur where a small municipality has been chosen as the case object to gather data. To achieve this purpose both primary and secondary data has been used to create a document analysis which has been complemented with interviews. The document analysis of the study aims to compile and compare previous projects in the municipality. The interviews are supposed to complement and explain different budget deviations found in the document analysis. Finally, a literature review was carried out in order to enable the comparison of the gathered data and increase the understanding of the findings. The result of the study is an explanation of why budget overruns occur in a small municipality. The primary reasons are change orders in the project plan which is caused by different factors. These different factors are faulty or vaguely formed project plans or even bad conditions of the land. Change orders are very cost and time consuming which causes budget overruns. The study also found that cost overruns are more common than time overruns.