Abstract: Interdisciplinary Nexus Science, Society, and Technology

Abstract:
The growing demand for energy efficiency in the building sector, which accounts for approximately 36% of global final energy consumption (UN Environment Programme, 2022), has driven innovation in adaptive façade materials. Thermometals, or bimetallic strips, are emerging as a promising solution for passive au tomation of interior thermal control. These composite materials, which dynamically respond to ambient tem perature fluctuations, represent a pivotal intersection between materials science and sustainable architecture, with the potential to significantly reduce reliance on mechanical HVAC systems. The methodology employed in this review analyzes the operating principle of thermometals, based on the differential coefficient of thermal expansion between two laminated metals (e.g., steel and copper). Their mechanisms of action are examined, enabling the design of adaptive façades with self-regulating capabilities for natural ventilation and shading. The integration of these systems is evaluated by considering computational design parameters, natural ven tilation strategies (stack effect and cross-ventilation), and their synergy with double-skin systems. Regard ing Results and Discussion: The implementation of thermometal façades demonstrates remarkable potential. Studies indicate that buildings with adaptive systems can achieve reductions in cooling energy consumption of up to 30–50% in temperate climates (Wörner et al., 2021, Q1). The ability of these materials to respond to environmental stimuli improves indoor thermal comfort by maintaining more stable temperatures, minimizing extreme thermal loads. However, their performance is subject to challenges such as weatherability, with a re ported lifespan that can vary from 7 to 15 years depending on the protective treatments, and the complexity of structural integration, which increases initial costs by 5–15% compared to conventional façades. Conclusions: Thermometals constitute a transformative technology for sustainable architecture, offering a pathway toward the decarbonization of the building stock. Their capacity for passive thermal self-regulation positions them as a key component in the design of nearly zero-energy buildings (nZEB). However, large-scale adoption is determined by the need to advance research into more durable and economical alloys, and the development of standardized design and integration protocols. The immediate future of this technology lies in its integration with intelligent building management systems (BMS) to further optimize its efficiency.