Identification of waste determining factors in the Kenyan construction industry

Abstract

Waste can significantly affect the business performance and productivity of contracting organisations. This study sought to investigate the sources, types and causes of waste within construction firms in Kenya focusing on design and construction firms. Literature was reviewed and gaps identified based on studies carried locally and internationally. Therefore it was noted that waste in construction is not only focused on the quantity of waste of materials on-site, but also related to several activities in design and construction phases. Based on contractors and design consultants' perceptions, data was collected through questionnaires from 39 respondents. Analysis of Variance' and Spearman's Rank Correlation tests were performed on43waste variables to establish their significance and causal links. The findings of the research suggest that thirteen (13) factors were found to be the significant variables that influence waste: measuring overall productivity; influence by contractors over design; manner (effectiveness) of information exchange between contractors and design consultants; incorporating waste minimization in processes; lack of trade skills; slow decision making; poor planning and scheduling; inappropriate construction methods; poor design; waiting for equipment to arrive; frequent equipment breakdown; materials not meeting specifications; and lack of effective supervision. These factors were significant in cost, quality and time performance of a project............................................