Time and cost impact of variation orders on construction projects in Kampala

Abstract

This research investigates the time and cost impact of variation orders, their causes, types and the measures to minimize their occurrence on construction projects in Kampala. Methodology A questionnaire survey was used to obtain responses from 50 project participants on the causes of variation orders and the cost and time implications they brought. Simple random sampling was used to obtain the sample size. The results showed that the variations had a significant effect and accounted for about 74.5 and 69 per cent of the cost and time overruns respectively, for the studied projects. A thorough study of the literature review was done to give a clear insight into the research hypothesis. Interviews were conducted with key experienced personnel on construction projects to obtain expert information about the research. The questionnaire responses were analyzed using the relative index (RI) method and a triangulation approach was employed to improve the validity of the results from the study. Findings The results showed that 38% and 62% of the respondents were males and females respectively. The clients were discovered to be the major initiators of VO, followed by the consultants and statutory bodies had little contribution to their emergence on construction projects in Kampala. Change in owner’s income was the leading cause of owner-related variations and design errors were the main causes of consultant-related variations. The variation orders had a great effect both on the time and cost of the studied projects. The RI of the beneficial impact of variation orders was between 47% and 22.5% while the RI of the detrimental variations was between 74.5% and 31%.

The project size and type depending on the contract sum were discovered to have no significant effect on the contribution of variations to the cost and time implications. The results also clearly displayed that changes in scope and specifications mostly by clients and consultants were the most dominant sources of variations on these projects in Kampala.