Ezinne Jane Oha (AUTHOR)
Department of Quantity Surveying, Imo State University, Owerri, Nigeria
Corresponding Author’s Email: ezinneezejane@gmail.com
ABSTRACT: The construction industry in developing countries continues to experience cost overruns, poor quality delivery, and maintenance challenges resulting from the engagement of non-professional labour and the imbalance of professional roles during project execution. This study examined the effects of these practices on construction costs and whole-life costing from the perspective of Quantity Surveying professionals in Owerri, Imo State, Nigeria. A descriptive survey research design was adopted, and structured questionnaires were administered to construction professionals comprising architects, engineers, builders, project managers, and quantity surveyors. Thirty-one valid responses were analyzed using descriptive statistics and percentage analysis. The findings revealed that although the engagement of non-professional labour may reduce initial construction costs, it significantly increases whole-life costs through poor workmanship, frequent maintenance, rework, and reduced durability of construction projects. The study also established that professional role imbalance weakens cost planning, financial accountability, and effective project control, thereby reducing value for money. The study concludes that sustainable construction delivery requires the active involvement of qualified professionals throughout the project lifecycle. It recommends stronger enforcement of professional regulations, improved role definition, continuous training of construction personnel, and wider adoption of whole-life costing as a decision-making tool for achieving sustainable construction outcomes.
Keywords: Construction cost; Whole-life costing; Quantity Surveying; Professional labour; Sustainable construction; Nigeria