FACTORS INFLUENCING REWORKS OCCURRENCE IN CONSTRUCTION: A STUDY OF SELECTED BUILDING PROJECTS IN NIGERIA

Abstract Rework has become a menace in Nigerian construction industry and it has not been given required attention, it contributes to time and cost overruns in project. Hence, to improve the performance of projects the research work evaluated rework in some selected building projects in Niger State. The work identified some factors contributing to rework which was categorized under three main headings; technical, quality and human resources factors to actually dig down into the casual of rework. A structure questionnaire was self administered on projects identified to have experienced rework amongst the selected projects and these were ranked according to their perceived degree of severity. Response was further condensed using factor analysis to group the variables into identifiable factors and thus analyzed. The study revealed that sub-standard services rendered by professionals and lack of commitment to quality in term of project delivery by stakeholders are the main source of rework. Therefore, it was recommended that an improvement and total commitment to quality of services render and assurance would lead to a reduction in the occurrence of reworks as revealed by the research

The impact of building information modelling on construction cost estimation

Construction, and of course, estimation processes are vulnerable to the limitations of spatiality in design and fragmented processes in entity-based CAD and manual design procedures. Whilst this challenge often leads to some tragic consequences, building information modelling (BIM) provides platforms for innovative and integrated design processes, and automated measurement. This development triggers the need for exceptional skills for intensive collaboration, project simulation, electronic data management, manipulation and handling of automated quantity measurement, simultaneous access to BIM design server and object-oriented design procedures wherein robust, clear and comprehensive information are underlain into project components. This study explores the impact of BIM on construction cost estimation. Samples of auto-measured BIM models are compared with existing standards and estimation procedures. Misconceptions about automated capacities of BIM and cost estimation are discussed. Recommendations are focused on further areas of research on the expectations of estimators on BIM models

Building information modelling processes: benefits for construction industry

Many industry reports have enunciated on the nature of complications in some forms of construction problems. These include design errors, deficiencies in estimates, conflicts in design and implementations, and fragmented platforms that restrict information flow all through project life. The nucleuses of these phenomena have been expressed as major concerns on project performance and sustenance of innovation in the industry. A peculiar dimension to this challenge is the ability of conventional design, procurement and construction management protocols to generate, share and convey, without dissipation at any point, all necessary project data across all stages and discipline boundaries in construction development processes and project life. As some observations have been drawn in literatures on the implications of fragmented systems and spatio-temporal limitations of hand-drawn and entity-based 2D CAD design systems, there has been significant attention on the limitations of these conventional design tools. These include weak frameworks to facility design flexibility, automation, integration, visualization and robust capacity to drive data creation, storage, engineering and sharing between parties. Whilst these challenges are being addressed in Building Information Modelling (BIM) platforms, some potential opportunities have been identified in BIM as reliable alternatives in facilitating marked improvements in design, procurement, construction planning and facilities management processes. This study reviews literatures on evidenced benefits of BIM, especially on how it reduces confrontation and system inadequacies of entity-based 2D CAD through thorough integration, collaboration, communication and interoperation. Conclusions are drawn on the challenges of changes from conventional paradigms which are triggered by BIM in relation to construction project goals