Green Building Awareness-Implementation Gap Among Built Environment Professionals in Lagos, Nigeria

Green building is a strategic response to continuous environmental degradation, energy inefficiency, and climate vulnerability associated with rapid urban sprawl, particularly in Lagos, Nigeria. While prior studies have established that built environment professionals in Lagos demonstrate moderate to high awareness of green building principles, empirical evidence consistently shows that this awareness has not translated into widespread adoption or full implementation in building projects. This study investigates the underlying reasons for this persistent awareness-implementation gap by adopting a sequential explanatory mixed-methods approach that integrates quantitative and qualitative evidence drawn directly from professional practice. Quantitative data surveyed 196 built environment professionals practicing in Lagos based on minimum professional experience (≥5 years), direct involvement in building design or delivery, and demonstrable awareness of green building principles. The quantitative analysis employed descriptive statistics, the Relative Importance Index, chi-square tests, and exploratory factor analysis to examine relationships between awareness, firm characteristics, perceived barriers, and levels of green building implementation.  Reliability testing confirmed strong internal consistency across all measurement constructs, with Cronbach’s alpha values exceeding accepted thresholds. The quantitative findings revealed relatively high awareness of green building strategies such as energy efficiency, passive design, and water conservation; however, actual implementation remains low and 
inconsistent. While firm size, years of establishment, and project typology were found to significantly mediate the translation of professional knowledge into practice, regulatory enforcement weakness, cost-driven client resistance, poorly coordinated project delivery structures, limited professional decision-making authority, and technical capacity constraints emerged as the most critical components of implementation. In triangulation, the qualitative analysis of 10 in-depth expert interviews revealed five themes: awareness without authority, short-term economic rationality, weak regulatory and institutional frameworks, poor interdisciplinary integration during project delivery, and an underdeveloped maintenance culture. The study establishes that green building challenges in Lagos are fundamentally implementation capacity problems rather than awareness deficits. The findings recommend a shift in policy and practice from awareness-focused interventions toward enforceable regulatory frameworks, client-oriented economic incentives, strengthened professional authority, and integrated project delivery models.