Regional retrofit, net-zero aspirations, and their whole-life carbon burden

Abstract Global surface temperatures have already exceeded the 1.5 °C target above pre-industrial levels. With net-zero decarbonisation efforts stalling, examination and revision of 1.5 °C – 2 °C compatible 2050 carbon budgets are crucial in prioritising actions across different sectors. In addition, many local administrations have historically set more ambitious deadlines compared to their national governments for achieving net-zero. In this context, we present a whole-life carbon evaluation and prioritisation of regional housing stock retrofit delivery in the UK. Three retrofit scenarios of fabric-only, systems-only, and a combination of both are compared based on their embodied and residual operational carbon emissions. We demonstrate the increasing policy relevance for local authorities in understanding the characteristics and inequalities in carbon emissions among diverse housing archetypes, and highlight the importance of archetype prioritisation in minimising carbon budget overshoots for different decarbonisation horizons. The results for regional and city-level housing stocks also demonstrate that, for the case study of South Yorkshire, any 1.5 °C compatible carbon budget will be exhausted within three years, even by integrating grid and material decarbonisation in retrofit deployment, regardless of the pace of stock decarbonisation. The extent of the carbon budget overshoot and the required retrofit delivery rates we present in this work put in sharp relief the realities of achieving regional net-zero ambitions.