Modeling the external drivers of green building investment: a PLS-SEM analysis of subjective norms

Purpose This study aims to investigate how multidimensional subjective norms within the theory of planned behavior (TPB) influence investor intention in green building projects in Vietnam. Addressing the oversimplification in prior TPB applications, subjective norms are decomposed into four empirically grounded dimensions: social demand, government support, readiness of project participants and certification organization support. This decomposition extends TPB theory by providing a context-sensitive framework that captures the complex institutional and stakeholder dynamics characteristic of emerging green building markets. Design/methodology/approach A structured questionnaire was developed based on systematic literature review and stakeholder consultations. Data were collected from 116 green building professionals with direct investment experience across Vietnam's three major regions (north, central and south) and analyzed using partial least squares structural equation modeling (PLS-SEM). The analysis evaluated both measurement and structural models, examining construct reliability, validity and hypothesized relationships. Findings Social demand (ß = 0.279, p < 0.01) and readiness of project participants (ß = 0.377, p < 0.01) significantly predict investor intention. Government support and certification organization support do not directly influence intention but operate indirectly by enhancing social demand (GOV→SOC: ß = 0.318, p < 0.01; CER→SOC: ß = 0.382, p < 0.01) and project participant readiness (GOV→PAR: ß = 0.504, p < 0.01; CER→PAR: ß = 0.320, p < 0.01). The model explains 42.1% of variance in intention, demonstrating the value of disaggregating subjective norms. Originality/value This study advances TPB theory by reconceptualizing subjective norms as a multidimensional, context-sensitive construct that reflects the institutional complexity of green building investment ecosystems in emerging markets. Unlike previous TPB extensions that add constructs linearly, this framework disaggregates a core TPB component to reveal nuanced mechanisms of normative influence. The findings demonstrate that institutional actors (government and certifiers) shape investor behavior primarily through legitimation mechanisms rather than direct pressure, offering actionable insights for policymakers and industry stakeholders.