Reuse of Tube Houses/Shophouses into Ultra‑Compact Co‑Living in Ho Chi Minh City: Trade‑offs in Space, Energy, and Social Cohesion after Renovation

Abstract

In Ho Chi Minh City, the tube house/shophouse is a dwelling‑cum‑trading typology. When converted into ultra‑compact co‑living, the “frontage—deep plan” organization together with alley culture generates new trade‑offs among: (1) spatial layout, (2) everyday energy‑use habits, and (3) the degree of social cohesion. There remains a lack of context‑rich research that details how architecture and culture interact in ultra‑small spaces after renovation. Method: a multi‑case qualitative study, including participant observation and go‑along walks with residents; semi‑structured, in‑depth interviews with homeowners, managers, and occupants; photo‑elicitation and resident‑produced photo diaries; architectural analysis through annotated sketches, narrative maps of movement flows and shared–private moments; and presentation via thick description to connect artifacts, rituals, and norms of conduct. Findings: three main points: (1) soft boundaries and buffer zones act as mechanisms for cultural negotiation; (2) the “commerce–dwelling” frontage, together with alley rhythms, shapes temporal “scenarios” of shared use; and (3) spatial props (curtains, shelving, benches, tea counters) guide co‑habitation rituals and form culturally inflected energy habits. Proposal: conceive architecture as the staging of ritual, prioritizing soft transitions and reconfigurability in design.