assessment of the effectiveness of design-bid-build and design-build delivery method in industrial parks development projects in Ethiopia

Abstract

Success or failure of any project is greatly influenced by the performance of cost, time and quality. The performance of each project may differ with the type of project delivery system used. Therefore, performance of projects under each delivery system should be considered in making the decision to select suitable procurement system. In Ethiopia Industrial Parks Development Corporation, DesignBid- Build and Design-Build are the two dominant project delivery systems used. As various study shows, construction projects in Ethiopia experience cost overruns, completed far behind schedule and are of low quality due to inappropriate project delivery method selection. Therefore the aim of this study is to assess the effectiveness and overall evaluation of Design-BidBuild and Design-Build project delivery systems in industrial park projects in Ethiopia. First factors which used to select Project delivery system, main causes for time and cost growth and factors which affect quality of the project were identified intensively from extensive literatures. In addition, other local factors (context to our country) have been added as recommended by experts and according to the researcher's own experience in implementing construction projects. Then data were collected from Industrial Parks Development Corporation archive, desk study, and interview & by questionnaire from clients, consultants, contractor’s Representative. Both primary and secondary data collection procedures were conducted. The research method used was quantitative non experimental method. Quantitative analysis was done by descriptive statistics and Relative importance Index (RII) technique was applied for ranking of critical factors. Accordingly, the factors used to choose appropriate Project delivery system are ranked using relative importance index (RII). The result shows top four factors used to select Design-Bid- Build are; Size and complexity of the project; Urgency of completing the project, Available budget for the project and Project design/ innovation. Whereas for Design-Build top four factors: Size and complexity of the project, Urgency of completing the project, Available budget for the project and Time. The main causes for time overrun (schedule growth) of design-bid-build projects are (top three factors) : - Right of way problem, inadequate planning, Contract scope change, Whereas the main cause of schedule growth for Design-Build project delivery system are (top three factors): -Right of way problem, inadequate planning and contract scope change modification. Similarly, the main causes for cost overrun (cost growth) of design- bid- build projects was additional works; time delay, inadequate pre-planning, take the top three causes for cost growth which is similar to Design-Build project delivery system. In addition, material, machinery and labor cost increment is the main cause of cost growth for Design-Build project delivery system. The research result shows also design- build system outperformed design-bid- build in terms of time and cost growth. The result and overall evaluation of this research is therefore encouraging(recommend) and very helpful for Industrial Parks Development Corporation to shift its Project Delivery Method from Design-Bid- Build to Design-Build so that by reducing main factors of cost and time growth identified for Design-Build project delivery method in this thesis.