ABSTRACT
Rework has become a menace in engineering procurement and construction projects in Nigerian oil and gas field. This study investigated the underlying causes of rework in construction projects and the impact on overall project performance so that effective containment and reduction strategies can be developed. The research was motivated by several international and local studies demonstrating a lack of concern for the root causes of rework and the potential impact on cost, overall project performance, and the ‘ non value-added ’ to the completed project. The research approach adopted included an exploratory and main study targeting purposively selected construction professionals and stakeholders in the Niger Delta area of the South-South region of Nigeria. The exploratory case study was carried out at the initial stage of the study to gain more insight into the causes and impact of rework on overall project performance. Specifically, data was collected by means of observation of physical works, semi-structured interviews with relevant parties directly involved in site operation and the analysis of site instruction record documents. The main study obtained data from 78 construction professionals and stakeholders via questionnaire survey, a survey conducted among design consultants and contractors in the general building category ranging from grade 3 to 9. Descriptive, inferential statistics and probability distribution functions were used to analyse the data. The findings revealed that changes initiated by the client, changes initiated by the design team due to errors and omissions, poor coordination, and finally, integration among the design team were the major contributing factors to rework. Moreover, non-compliance with specifications, setting-out errors, low labour skills, and emphasis on time and cost aggravated the occurrence of rework on site. The study revealed that while there is no significant difference between the causes of rework and various project types, rework can and often does make a significant contribution to any project’s cost overrun.
