ORCID
0009-0000-6706-9668
Abstract
Consultancy-related variations remain one of the leading causes of cost overruns, schedule delays, quality deficiencies, and contractual disputes in public building projects. Although various studies have been undertaken to document the causes of variations in construction works, the same level of interest has not been shown for consulting services variations across the consulting services spectrum and their consequences for effective management. This study explores variations in consulting services for public works by systematically reviewing the existing literature using the PRISMA (Preferred Reporting Items for Systematic reviews and Meta Analyses) guidelines. Relevant articles published from 2020 to 2026 were retrieved from the major scientific databases. The archival search yielded 70 articles, of which 41 were included and subjected to qualitative review. Consultancy-related variations were documented at each stage of the feasibility study, preliminary design, and detailed design. Variations were attributed to engineering design errors and omissions, incomplete or missing drawings, design inconsistencies, specification changes, poor coordination, inadequate site investigations, and failure to comply with the client's requirements and relevant authorities' requirements. The variations resulted in increased costs, delays, and rework, decreased project quality, and disputes with stakeholders. The studies showed that most related work focuses on establishing cause and effect, while an integrated approach to managing variations was largely ignored. Therefore, this study determines the variations and their consequent impact across the consulting services spectrum to provide a basis for managing variations caused by consulting services. The focus is on improving variability in consulting services, managing variations in consulting services, and optimising the delivery of public works.
Recommended Citation
Bambaza, G., Taifa, I. W., & Mwaluko, G. S. (2026). Exploring Consultancy-Related Variations in Public Building Projects: A Review Towards a Management Framework. Tanzania Journal of Engineering and Technology (TJET), 45(2), 55-68. https://doi.org/10.65085/2619-8789.1794
Publisher Name
University of Dar es Salaam
Included in
Industrial Engineering Commons, Other Operations Research, Systems Engineering and Industrial Engineering Commons, Risk Analysis Commons