Bringing nature home: promoting multi-species justice through building retrofit

The Committee on Climate Change (CCC) recognises that building retrofit and biodiversity recovery are essential to meeting the UK’s environmental commitments. However, retrofit practices pose an overlooked risk to cavity-dependent species of birds, bats and insects through the hermetic sealing of building envelopes. This research aims to discover the current level of integration between biodiversity within retrofit systems and assess the effectiveness of artificial habitats as conservation tools. This review establishes existing literature on the alignment between retrofit and nature recovery. The results revealed that biodiversity and retrofit governance currently operate separately. Significantly, permitted development rights apply to most domestic retrofit, this means that retrofit does not involve the same Biodiversity Net Gain (BNG), environmental assessment or reporting and monitoring requirements that apply to new developments. These findings demonstrate the oversight of the cumulative impact of domestic retrofit to the environment. Additionally, there is a disconnect between empirical evidence and local plans that are integrating artificial habitats, meaning that adherence to maintenance and reporting regulation will be critical to avoid negative outcomes. With retrofit across 30 million homes imminent in the UK alone (under the Warm Homes Plan), ensuring that retrofit is accounted for in biodiversity strategies is crucial to reducing habitat pressures caused by urban expansion. If ignored we risk undermining current efforts towards decarbonisation and nature recovery and risk the displacement of legally protected cavity-dependent species. This review demonstrates the potential for existing buildings to contribute to both decarbonisation and nature recovery, supporting a climate-resilient built environment.