Biophilic Architecture and Quality of Life in a Geriatric Residence: Correlational Analysis and Empirical Hierarchization of Design Dimensions–A Case Study in Metropolitan Lima

International evidence positions the built environment as an active component of the quality of life of older adults; however, the empirical quantification of that relationship and its hierarchization to guide design decisions in Latin American geriatric residences remain a persistent gap. Against this background, the present study examined how biophilic architecture relates to the quality of life of older adults residing in a geriatric residence in the Cercado de Lima district, adopting a single-case study approach. A quantitative approach with a non-experimental, cross-sectional, and correlational design was adopted. The sample comprised 81 proxy informants, relatives in close and ongoing contact with the residents, recruited by non-probabilistic convenience sampling. A structured questionnaire of 25 Likert-scale items, each with five response categories, was used to gather the data, administered through the QuestionPro platform. Content validity was established through the judgment of three architecture specialists; reliability was confirmed through Cronbach’s alpha coefficient (α = 0.943). Given that the data did not follow a normal distribution (Shapiro–Wilk, p < 0.05 in 9 of 10 variables), the inferential analysis relied on Spearman’s rho coefficient, with Kendall’s Tau-b as a complement. The results revealed a positive, statistically significant, and large-magnitude association between biophilic architecture and quality of life (ρ = 0.792, p < 0.001). Dimensional analysis identified a hierarchical pattern organized in two statistically distinguishable levels. In biophilic architecture, a first level comprised the nature of the space (ρ = 0.792) and sensory stimulation (ρ = 0.783), and a second significantly lower level comprised natural analogs (ρ = 0.621) and nature in the space (ρ = 0.605). In quality of life, a first level comprised physical health (ρ = 0.763), social relationships (ρ = 0.753), and psychological health (ρ = 0.720), and a second level comprised environment (ρ = 0.564); coefficients within each level did not differ significantly, whereas the difference between levels was significant. The obtained empirical hierarchization was translated into evidence-informed design orientations, offering architects and facility managers a non-prescriptive guide for setting design priorities where infrastructure is limited, in alignment with Sustainable Development Goals (SDGs) 3 and 11. The study was conducted through proxy informants, family members with direct and sustained contact with the resident, a methodological configuration recognized in the specialized literature on institutionalized older adults and whose perceptual mediation remains as a residual consideration of the design when interpreting the findings. As a single-case study, the findings characterize the analyzed institutional context and constitute transferable hypotheses to be verified in further residences rather than generalizations to the broader population of geriatric residences.