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

Green building, a strategic response to continuous environmental degradation, energy inefficiency, and climate vulnerability associ-ated 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 to full implementation in building projects. This study investigates the under-lying 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 envi-ronment professionals practicing in Lagos based on minimum professional experience (≥5 years), direct involvement in building de-sign or delivery, and demonstrable awareness of green building principles. The quantitative analysis employed descriptive statistics, Relative Importance Index, chi-square tests, and exploratory factor analysis to examine relationships between awareness, firm charac-teristics, 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 sig-nificantly mediate the translation of professional knowledge into practice, rregulatory enforcement weakness, cost driven client re-sistance, poorly coordinated project delivery structures, limited professional decision-making authority, and technical capacity con-straints 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 estab-lishes 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 frame-works, client oriented economic incentives, strengthened professional authority, and integrated project delivery models.