Conceptualising the “Fourth Space” in Aged Care Environments: A Design Framework Informed by Melbourne and Chinese architecture

摘要

Amid the acceleration of global aging, the lack of emotional companionship and social connection has become increasingly prominent among the aged population. However, traditional aged care spaces continue to follow the functionalist logic of medical architecture, making it difficult to respond to residents’ emotional needs for “companionship” and “being seen.”

Based on the author’s nearly 20 years of experience in medical and aged care services, as well as three months of field observations in Melbourne in early 2026, this paper proposes the concept of a “Fourth Space” and develops a corresponding theoretical framework for aging societies.

The study first reviews global aging trends and the dilemma of emotional companionship among the aged population, arguing that “social interaction” emphasised by traditional Third Place theory may, in elderly care contexts, transform into a source of social pressure. Through continuous observation of Federation Square and the National Gallery of Victoria in Melbourne, this study finds that high-quality public spaces are shifting from “promoting interaction” to “allowing coexistence.” Their characteristics, such as weak boundaries, non-mandatory interaction, and what the paper terms “environmentalised companionship”, offer new insights for the design of aged care space.

On this basis, the paper defines the “Fourth Space” as a transitional environment between private and public spaces, emphasising a mode of presence characterised by coexistence rather than active communication. It further proposes three key design directions: (1) minimal boundary construction, which reduces psychological defense by blurring spatial boundaries; (2) non-mandatory interaction mechanisms, which allow individuals to coexist in diverse ways without forced communication; and (3) an AI-enabled environmental companionship system, which integrates artificial intelligence into spatial environments to form low-intervention, long-term companionship relationships.

The study further validates the feasibility of this framework through practical cases in Chinese aged care institutions, demonstrating that the “Fourth Space” can be gradually implemented through incremental spatial optimisation. The findings suggest that the “Fourth Space” is not only an extension of the Third Place theory in aging contexts, but also a crucial spatial paradigm for addressing emotional needs in aging societies, offering both theoretical and practical implications for future aged care models.