Carbon budget for national building stock life-cycle emissions: a novel approach

Following the Paris Agreement, many countries such as Switzerland or Denmark have derived carbon budgets for their national building stock to support local policies by creating benchmarks. The aim is to calculate a quota for carbon emissions that a country can spend on its building stock by 2050 to ensure that it stays within a 1.5°C trajectory. The underlying allocation principle almost exclusively follows this procedure: (i) allocating the global budget to the national level, (ii) further allocating the national budget to the sectoral level, and (iii) to the building stock level (or even further down to the district or building level). However, this procedure of budget allocation does not do justice to the cross-sectoral and international nature of the national building stock’s life-cycle emissions. We propose a new approach for consistent, building stock-specific carbon budgets and demonstrate the proposed methodology for Austria. Adopting this approach for the building stock of other countries would enable consistent carbon budgets that reflect the field of action buildings for climate change mitigation.