Urban environments are becoming increasingly inhospitable for those least equipped to cope. Heat waves are intensifying across cities globally, while cold, damp, and thermally precarious housing continues to trap millions in cycles of energy poverty and compromised wellbeing. These thermal risks map onto pre-existing geographies of social disadvantage, housing precarity, and uneven infrastructural provision. Addressing them requires more than better building performance metrics or expanded cooling facilities. It requires a conceptual framework capable of connecting the physical condition of buildings with the social conditions of the people who inhabit them.
This keynote develops the concept of thermal security as such a framework. Drawing on Giddens' notion of ontological security, thermal security refers to the stable confidence individuals have in the reliable availability of protective thermal environments—adequate housing, affordable energy, accessible public cooling infrastructure, and responsive public services—that allow everyday routines and existential stability to be maintained. When these systems become intermittent, unaffordable, or exclusionary, thermal security erodes. The concept is organized around five interconnected dimensions: exposure, access, affordability, emotional impact, and coping strategies—together providing a sociologically grounded lens for assessing adaptation needs and justice-oriented responses in urban contexts.
The framework emerges from comparative research across Chile and Spain. In southern Chile, fieldwork in cities such as Coyhaique, Temuco, and Osorno has documented how low-income households are trapped in a dilemma between breathing clean air and cheaply heating their homes, a dilemma rooted in energy poverty, poor housing quality, and inadequate thermal insulation. A mixed-methods study of thermal retrofitting in vulnerable urban housing demonstrates that building envelope improvements translate into measurable reductions in cold-related health problems, sleep disruption, and financial stress, while also reshaping the relational and emotional dimensions of home life. Retrofit, in this light, is an act of distributive and recognitive justice.
In Spain, ongoing research examines urban heat vulnerability through the same lens. A developing study of climate shelters in Barcelona, combining spatial analysis, survey data, and ethnographic fieldwork, shows that the protective capacity of these facilities is far more limited than official coverage figures suggest. Spatial mismatches, restricted operating hours, and subtle interactional barriers produce thermal insecurity even where infrastructure nominally exists.
Taken together, these empirical lines point toward a conclusion relevant to the sustainable built environment community: adaptation cannot be reduced to technical efficiency or exposure metrics alone. A thermally just city is one where all residents—regardless of income, tenure, or social position—can maintain safe thermal conditions as a foundation for dignified everyday life. Designing and retrofitting that city requires social knowledge alongside technical expertise.