Why Thermal Comfort is Elusive—The Role of Socio-Cultural Factors

Summary of a paper presented at the joint 45th AIVC conference and ASHRAE 2025 Summary of a paper presented at the joint 45th AIVC conference and ASHRAE 2025 IEQ conference “IEQ 2025: “Rising to New Challenges: Connecting IEQ to a Sustainable Future” will be held on September 24-26, 2025, in Montreal, Quebec together with the 13th TightVent and the 11th venticool conferences.

Key Words: Thermal comfort, socio-cultural factors, indoor environmental quality (IEQ), HVAC design, behaviour, ethnography, human-centred design

Thermal discomfort is far too common. This article discusses the complexities associated with achieving thermal comfort in buildings, focusing on the influence of socio-cultural factors and how to better account for them.

Understanding Thermal Comfort and Its Complexity

Thermal comfort is a multifaceted experience influenced not just by physiological and psychological factors interacting with the physical environment, but also by socio-cultural factors. Thermal comfort, and comfort in general, while socio-technic in nature is largely socially constructed.

·         Thermal comfort is defined as a subjective state of mind reflecting satisfaction with the surrounding thermal environment.

·         Twelve factors impact thermal comfort, including air temperature, humidity, and occupant metabolic rates (see Table 1).

·         Admitting that we don’t effectively account for all twelve factors to begin with, socio-cultural dimensions add to this complexity, significantly impacting thermal comfort experiences.

·         The paper emphasizes the need for a broader understanding of thermal comfort that includes socio-cultural influences – norms, policies, and behaviours.

Table 1. Conventional thermal comfort factors, per ANSI/ASHRAE Standard 55-2023, grouped into four categories: Space / Room Level Factors describing average room or space conditions, Local Spatial Factors describing local conditions at the occupant, Temporal Factors describing changes in room conditions over time, and Occupant Factors describing specific occupant characteristics.

Socio-Cultural Influences on Thermal Comfort

Cultural norms, organizational policies, social dynamics, and individual behaviours play a crucial role in shaping thermal comfort experiences.

·         Cultural scripts learned during upbringing influence expectations, perceptions, and reactions to thermal environments.

·         Variations in thermal comfort needs arise from cultural and climatic backgrounds, affecting clothing choices and adaptive measures.

·         Socioeconomic factors impact thermal comfort perceptions as well as the ability to achieve thermal comfort. For example, lower-income students often face more challenges being thermally comfortable.

·         Standardized HVAC systems may conflict with normative comfort behaviours and vernacular traditions, reinforcing dominant norms and leading to inequities and dissatisfaction.

The Role of Clothing and Demographics

Clothing choices and other demographic factors significantly affect thermal comfort experiences among different individuals and groups.

·         Social norms around clothing can create conflicts in thermal comfort preferences, especially when there is a high degree of variation in norms present among the building occupants.

·         Demographic and individual characteristics such as age, gender, skin-to-mass ratio, and cultural values influence clothing preferences and subsequent thermal comfort experiences.

·         Women often report higher dissatisfaction with thermal comfort due to overcooling, societal clothing norms, and related organizational and building operational policies.

·         Historical dress codes have been influenced by dominant gender norms (often reflecting cisgendered men), affecting thermal comfort for minority groups.

Behavioural Adaptations and Social Dynamics

Occupants often adapt their behaviours to achieve thermal comfort, influenced by the social dynamics present in shared spaces.

·         Behavioural adaptations include changing activity levels, changing locations, modifying clothing types and layers, and adjusting environmental controls.

·         Access to controls, combined with a sense of belonging and trust among the occupants, increases the likelihood of occupants taking adaptive actions.

·         Social dynamics, power differentials, and organizational policies may limit adaptive actions, leading to conflicts over environmental control, impacting relationships, collaboration, and trust among occupants.

·         A shared sense of purpose can enhance satisfaction with thermal comfort in shared environments.

·         By providing clear, predictable, accessible, and effective ways to manage thermal comfort, buildings provide occupants the affordances needed to overcome stress and illness.

Importance of Control Interface Design

The design of control interfaces is crucial for meeting diverse occupant needs and expectations regarding thermal comfort, impacting whether occupants feel empowered or frustrated maintaining thermal comfort.

·         Socio-cultural differences affect the usability and effectiveness of building control interfaces, including those of thermostats, switches, and window shades.

·         Language, symbols, normative default states, and policies can limit access to controls, impacting occupant behaviour and experiences.

·         The infancy of control interface design relative to socio-cultural factors is one reason personalized controls are typically more successful meeting occupants’ needs.

·         A cross-cultural validation process is recommended for improving the usability of controls.

Utilizing Ethnography to Enhance Thermal Comfort

Ethnography, originating in the field of anthropology, provides valuable insights into the socio-cultural factors influencing thermal comfort as well as how to more effectively address those factors in design and operations. For anthropology, the smallest unit of study isn’t an individual, but the relationship between two people and their environment. Hence, thermal comfort as a social construct (see Figure 1).

·         Ethnography involves systematic observations and engagement of occupants within their environments to understand their diverse needs, experiences, and encompassing social dynamics, providing a clearer picture of the diversity present among occupants (and operators).

·         Key steps include discovery, collection, processing, analysis (to generate insights and recommendations), and reporting of findings related to project goals.

·         Ethnography provides a holistic understanding of occupant experiences by engaging occupants within their day-to-day environments and experiencing firsthand those environments, relationships, and activities, essential for identifying behavioural and environmental drivers and barriers to thermal comfort.

Figure 1. Experiences, including comfort, are relational, not just individual. Thermal comfort is shaped by socio-economic background, socially defined activity levels, organizational policies, clothing norms, occupant interactions, etc.

Key Concepts for Ethnographic Assessment

Four concepts guide ethnographic assessments to optimize thermal comfort and occupant experience in general.

·         Context: Engaging occupants in their spaces and observing behaviours where they occur reveals constraints and opportunities, especially the critical nuances associated with each.

·         Partnership: Building trust with occupants enhances the quality of insights gathered during assessments – they are the experts in their own experiences.

·         Interpretation: Assigning meaning to observations helps identify design implications for improving thermal comfort, but these assigned meanings must be verified with the occupants and operators.

·         Perspective: Acknowledging diverse viewpoints ensures that all relevant groups, including marginalized groups, are represented.

Takeaways for Designers and Operators

Ethnography is a valuable tool for uncovering socio-cultural influences on thermal comfort, particularly as part of an integrated design process fostering communication among stakeholders, reducing assumptions and increasing transparency.

·         Incorporate socio-cultural factors into modelling, thermal comfort calculations, design targets, and envelope/HVAC strategies.

·         Engage occupants and operators early through ethnography, workshops, prototypes, etc.

·         Design and specify control interfaces for cultural relevancy, clarity, accessibility, and equity. Pay attention to ongoing research in this area.

·         Use ethnography to uncover the nuances associated with occupant experiences, the hidden drivers of comfort (including socio-cultural factors), and to inform design and operational decisions.

·         Recognize that thermal comfort influences collaboration, trust, health, and productivity.

·         Involving behavioural scientists and trained professionals can lead to a deeper understanding of the social, along with increased project success.

Conclusion

Thermal comfort, in addition to being a physiological and psychological response to the surrounding environment, is a socio-cultural construct shaped by norms, behaviours, and organizational policies. By integrating ethnographic methods, previously generated understandings of the social, and subsequent contextual behavioural insights, practitioners are better positioned to create buildings that are not only technically sound but also equitably responsive to diverse occupant needs.

Acknowledgments and Contributions

The authors would like to acknowledge the support received from BranchPattern for their time to produce this paper.

References

ANSI/ASHRAE. 2023. ANSI/ASHRAE Standard 55-2023 Thermal Environmental Conditions for Human Occupancy. Peachtree Corners, GA: American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE).

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