Sick Building Syndrome (SBS) has emerged as one of the most significant health challenges of contemporary urban life, reflecting the complex interaction between architecture, environmental design, and human psychology. As urbanization intensifies and people spend most of their time indoors, the physical and psychological conditions of residential environments have become critical determinants of public health. SBS refers to a set of non-specific physical and psychological symptoms that appear among building occupants and tend to improve or disappear once they leave the affected space. These symptoms range from eye and skin irritation, headache, fatigue, and concentration difficulties to emotional disturbances such as anxiety, stress, and paranoia. While numerous studies have explored SBS in offices, schools, and urban spaces, research focusing on residential buildings—where people spend most of their lives—remains limited, particularly in developing contexts. This study addresses this gap by examining the relationship between environmental quality and SBS symptoms in a large residential complex, emphasizing both physical and psychological dimensions, especially the often-overlooked component of paranoia.
The research was conducted in the Mehr Housing Complex in Borujerd, Iran, which serves as a representative example of medium-density urban housing developed through national affordable housing initiatives. A descriptive–analytical methodology was employed, utilizing quantitative survey analysis to evaluate the impact of environmental quality on both physical and psychological aspects of SBS. The conceptual framework posits that residential environmental quality—including architectural layout, visual access, ventilation, lighting, and proximity to nature—significantly influences physical comfort and psychological stability.
A sample of 378 residents was selected using Cochran’s formula to ensure representativeness and statistical validity. Data collection used three primary instruments: a researcher-designed questionnaire assessing 26 environmental quality indicators, the standardized SBS questionnaire for physical symptoms, and the Symptom Checklist (SCL-90) focusing on paranoia as a psychological indicator. Instrument reliability was confirmed by Cronbach’s alpha coefficients ranging from 0.79 to 0.89, indicating satisfactory internal consistency and stability. These measures facilitated a comprehensive analysis of residents’ perceptions of their built environment and the correlation with physical and mental well-being.
Descriptive statistics indicated moderate levels of SBS symptoms among residents. Approximately one-third of participants reported low to moderate physical symptoms, with a similar pattern observed for psychological distress, including paranoia. The mean scores for the physical SBS index and paranoia were 2.61 and 2.87, respectively, reflecting moderate-to-low prevalence. These results suggest that, although SBS is not severe across the population, environmental factors have measurable effects on health perceptions and psychological balance.
To identify predictive relationships, Pearson’s correlation and multiple linear regression analyses were conducted using SPSS. The initial regression analysis examined each environmental indicator separately in relation to the physical SBS index and the paranoia index. Nine environmental indicators were found to predict physical SBS symptoms significantly. Of these, “visual depth to distant landscapes” exhibited the strongest standardized regression coefficient, indicating that access to open, far-reaching visual perspectives, such as views of greenery or natural scenery, significantly reduces physical discomfort. Other influential indicators included adequate ventilation, acoustic control, and the use of calming colors in interior spaces. These findings underscore the importance of visual and sensory comfort in mitigating the physiological aspects of SBS.
In the subsequent regression model, environmental quality was analyzed as a composite variable that combined the effects of all 26 indicators. This model accounted for approximately 25 percent of the variance in physical SBS symptoms (Adjusted R² = 0.25). While not the primary determinant, this proportion is statistically significant and confirms that architectural and environmental characteristics, particularly lighting, ventilation, and visual openness, are substantial contributors to physical health outcomes in residential settings.
Regarding the psychological dimension, results indicated an even broader environmental influence. Thirteen environmental indicators significantly predicted paranoia levels among residents. The most influential predictors were “access to green spaces” and “view to green areas,” both of which demonstrated significant negative correlations with paranoia. Residents with greater access to and visibility of natural elements reported lower levels of distrust, anxiety, and intrusive thoughts. The regression model for psychological symptoms explained 26 percent of the variance in paranoia (Adjusted R² = 0.26), indicating that environmental quality consistently and meaningfully contributes to psychological stability, even if the effect size is moderate. These findings support existing evidence in environmental psychology that contact with nature and visual openness facilitate mental restoration and stress reduction. ANOVA results confirmed the statistical validity of both regression models, with F-tests significant at p < 0.001, indicating a good overall fit of the proposed models. These outcomes underscore that the conceptual framework is theoretically sound and empirically supported. The models demonstrate that improvements in environmental quality can simultaneously alleviate physical discomfort and reduce psychological distress among residents, underscoring the integrated nature of environmental health.
One of the key innovations of this research is its methodological integration of architectural and psychological perspectives. By employing the SCL-90 inventory alongside environmental indicators, the study provides a dual lens through which the multifaceted nature of SBS can be understood. While prior research often limited SBS analysis to air quality and building materials, this study emphasizes the psychological correlates of spatial design, focusing on paranoia as a rarely examined dimension. Paranoia, in this context, refers not to clinical delusion but to mild and pervasive feelings of distrust or hypervigilance triggered by spatial enclosure, lack of control, or insufficient access to natural views. Identifying this link between spatial configuration and psychological response advances theoretical understanding in environmental psychology and psychosomatic health. The implications of this study extend beyond academic research to inform practical urban planning and architectural design. The findings suggest that modest adjustments in residential design, such as ensuring adequate daylight penetration, maintaining visual transparency toward outdoor spaces, reducing interior crowding, and incorporating semi-public green terraces, can collectively improve residents’ health outcomes. Specific recommendations include enhancing ventilation systems, providing green buffers between buildings, and designing facades that balance privacy with exposure to natural elements. These strategies align with global sustainable design principles that integrate physical comfort, psychological well-being, and environmental performance in housing policies. policies.
Moreover, the study highlights the importance of interdisciplinary collaboration among architects, urban planners, environmental psychologists, and public health professionals. The findings advocate for integrating mental health considerations into residential design standards and urban development guidelines. This integration could include adding psychological health appendices to building codes or developing specialized assessment tools to evaluate the mental restorative potential of built environments. Such initiatives would ensure that future residential projects address not only structural and aesthetic requirements but also promote emotional resilience and cognitive well-being among occupants., This research contributes to expanding the discourse on SBS by establishing its dual physical–psychological framework. The evidence that environmental factors explain approximately one-fourth of the variance in both physical and psychological symptoms suggests that SBS is neither purely architectural nor exclusively psychological—it is an emergent outcome of the interaction between environmental design and human perception. Future research should explore longitudinal studies and experimental interventions to clarify further causal pathways and test design prototypes that directly target mental restoration in residential contexts.
In summary, this study demonstrates that residential environmental quality plays a statistically significant yet often underappreciated role in shaping both the physical and psychological dimensions of Sick Building Syndrome. Improvements in environmental quality—such as increased natural light, ventilation, visual access, and integration of green spaces—can effectively reduce discomfort, paranoia, and psychological tension among residents. These findings advocate for a paradigm shift in housing design and urban planning, explicitly incorporating evidence-based principles from environmental health and psychology. Strengthening collaboration between architecture and behavioral sciences enables residential design to move beyond aesthetics toward a holistic model of well-being, recognizing the built environment as both a determinant and mediator of human health.