The role of grey space in creating socially engaging learning environments: a comparative study of higher education buildings in Bangkok

Purpose Circulation and transitional “grey spaces” in higher education buildings are often minimized as residual areas, despite their potential to support informal learning, social exchange, and environmental responsiveness. This study reconceptualizes circulation as an active spatial infrastructure and examines how it shapes student experience in a tropical Asian context. Design/methodology/approach A comparative mixed-methods study was conducted across three university buildings in Bangkok: one baseline case and two award-winning designs. A structured survey of 90 users was combined with on-site observations. Circulation was evaluated across four dimensions: human-to-human interaction, human-to-nature connection, sustainability and aesthetics, using descriptive statistics, ANOVA and thematic analysis. Findings Significant differences were identified among the cases (p < 0.05). Courtyard-centered and semi-outdoor systems performed strongest, fostering social engagement, environmental comfort and inclusivity. Efficiency-driven corridor layouts scored consistently lower across all dimensions. The results demonstrate that circulation design directly influences educational experience and institutional identity. Research limitations/implications The study is limited to three cases within a single metropolitan context and relies primarily on user perceptions rather than long-term behavioral or environmental performance data. Nevertheless, it proposes an integrated analytical framework that synthesizes fragmented literature on circulation by operationalizing it into four measurable dimensions. The research extends discussions on informal learning environments by providing comparative empirical evidence from a tropical Asian setting and offers a transferable conceptual model for future cross-cultural and longitudinal investigations. Practical implications The findings suggest that circulation should be treated as a strategic design component rather than minimized for efficiency. Courtyard-centered and semi-outdoor systems can enhance passive comfort, social interaction and spatial flexibility in tropical climates. Architects and campus planners are encouraged to integrate shading, ventilation, greenery and adaptable seating within circulation networks to strengthen informal learning and institutional cohesion without extensive classroom expansion. Social implications By enhancing belonging, inclusivity, and everyday social exchange, well-designed grey spaces contribute to student well-being and campus identity. In resource-constrained contexts, investing in circulation offers a cost-effective way to improve educational quality and environmental awareness, reinforcing the social role of architecture in shaping equitable and sustainable learning communities. Originality/value The study introduces a four-dimensional analytical framework that integrates social, environmental, and esthetic perspectives on circulation. By providing comparative empirical evidence from a tropical higher education context, it advances architectural research on informal learning environments and offers a transferable model for climate-responsive campus design.