Rethinking Urban Surfaces: Geometry-Driven Thermal Solutions for Wild Bee Habitats

Urban surfaces, far from static architectural elements, actively mediate ecological and climatic processes in cities. This study is part of a PhD project at IntCDC, University of Stuttgart. It reimagines urban facades as inclusive interfaces that address the comfort needs of both human and non-human inhabitants. Using wild bee nesting as a focal case study, it investigates strategies to regulate nest temperatures, mitigating the detrimental effects of elevated heat, such as developmental delays, metabolic stress, and offspring mortality. Wild bees, as primary pollinators, are essential to biodiversity and urban ecosystem functioning, enhancing green infrastructure by supporting plant reproductive success and contributing to urban resilience. Urban surfaces offer opportunities to create continuous networks of nesting and foraging resources, fostering ecological connectivity within the built environment. By serving as permeable interfaces, they enable species movement, resource access, and the maintenance of genetic diversity necessary for adaptation to climate change. This study explores geometry-driven solutions, employing porous, cellular structures for their thermodynamic properties and potential to support diverse species. Additive manufacturing was used to fabricate these complex, adaptive geometries, which were tested alongside a traditional nesting aid on a southeast-facing facade in Stuttgart, Germany. While the 3D-printed designs showed moderate thermal benefits, their significance lies in reimagining urban surfaces as active contributors to ecological resilience. This work highlights the potential of a more-than-human design approach, positioning urban surfaces as adaptive, multifunctional systems that promote biodiversity and address contemporary environmental challenges, aligning with emerging legal and policy frameworks.