Impact of Variation on the Cost Performance of Public Building Projects in Birnin Kebbi, Nigeria

Abstract

Variations are an unwelcome but unavoidable part of any construction project, and they are the most common source of claims that lead to time and cost overruns. Projects with a lot of variation cause the contractor's production to be lower than expected. The impact of variation on the cost performance of public building projects was investigated in this study. Through a well-structured questionnaire, primary and secondary data were gathered from the Kebbi State Housing Corporation and the Kebbi State Ministry of Works and Transport, BirninKebbi, through which 58 questionnaires were administered and 52 retrieved. Correlation analysis, the Relative Importance Index (RII), the Mean Item Score (MIS), and the Relative Importance Index (RII) were used for the data analysis. Changes in specifications were determined to be the most common cause of variation on public building projects (RII = 0.96). It was also revealed that the initial and final contract sums have a strong, positive, and significant link. The most effective technique for reducing the frequency of variation was determined to be client, consultant, and contractor efforts to restrict variation orders (MIS=4.89). The influence of variation on the cost performance of public building projects was shown to be significant.