Toward a Theory of Construction Cost Governance in Sub-Saharan Africa: Empirical Evidence from Nigeria

Construction cost governance, encompassing the systems of authority, accountability, professional norms, and institutional arrangements that shape how construction costs are managed in public and private sectors, has not been theorised at a national level for sub-Saharan African countries. This study develops a theory of construction cost governance grounded in empirical evidence from Nigeria. A critical realist philosophy and abductive reasoning strategy underpin a comprehensive mixed-method design, employing 80 semi-structured expert interviews, a national survey of 310 quantity surveyors and public sector clients, institutional analysis of 40 regulatory frameworks, and comparative case studies of construction cost governance in 6 Nigerian geopolitical zones. Grounded theory coding, structural equation modelling, and comparative institutional analysis provided the analytical tools. Findings reveal that construction cost governance in Nigeria is characterised by fragmented authority, weak accountability chains, professional capacity deficits, and a low-trust institutional environment that collectively undermine cost management outcomes across sectors. Three distinct governance models are identified (market-led, state-directed, and hybrid), with hybrid models demonstrating the best cost performance outcomes when supported by strong professional regulation. The resulting Nigerian Construction Cost Governance Theory (NCCGT) provides a multi-level explanatory framework integrating institutional, professional, and project dimensions. This research makes a foundational theoretical contribution to construction cost management science in sub-Saharan Africa, with implications for professional regulation reform, public sector capacity building, and international development programming. Keywords: cost governance, theory building, Nigeria, sub-Saharan Africa, construction cost management