Buildings can support biodiversity. And cities can catalyze that shift with tested, implemented policies. Presented at Davos 2025, 'Catalysing Biodiversity on Buildings’ documents European cities that are leading the way with innovative policies and tools to advance biodiversity on buildings.

In collaboration with IUCN and Holcim, Second Nature utilized our experience with biodiverse building design, research and synthesis skills, and interviews with European city leaders to develop this new perspective on how cities can support nature in the built environment.

The report explores 8 pioneering European cities that are leading the way with innovative actions and policies to enhance biodiversity at the building scale. From green roofs that provide habitats for pollinators to wildlife-friendly and bird-safe architectural principles, these cities are setting inspiring examples of how urban environments can coexist with nature, improving human health, well-being and social cohesion.

In the report, we identify:

• Best practices for incorporating biodiversity into urban design.

• Successful incentives and policy frameworks driving change.

• A roadmap for scaling these solutions globally.

The report highlights demonstrated mechanisms for the integration of nature and biodiversity into the building scale, through the measures implemented within the individual building structure. Actions include green roofs and walls, measures to safeguard wildlife against building hazards like reflective surfaces, and special resources such as nesting boxes and refuge for pollinators. The document provides context by reviewing global agreements and initiatives that support these themes, and discusses leading examples from global cities before providing a more in-depth review of the range of initiatives from eight European municipalities.

As urbanization rates continue to rise, these examples demonstrate that cities can be part of the solution for a greener and more biodiverse future.