This research concern in space invasion as living expression from slum settlement in riverbank area. It aims to propose schematic designs of collective housing with a flexible architecture concept on that space invasion lifestyle. This research used several tool and qualitative techniques of collecting data and merge it as a force for designing the housing. The design innovation is the flexibility of social space and participant activities. The application of the concept is demonstrated by creating organizational relationships between unit space, between residential units and between buildings and the flexible use of architectural elements. The design also highlights the formulation of technological concepts and applications in the field of Architectural Design and Behavior approach based on the phenomenology of marginal communities on the riverbank settlement.