Circularity in the Built Environment 2024

About the analysis BOX 2 The goal of the analysis in this white paper is to quantify the material (in tonnes and cubic metres) required for retrofits and determine the portion that could be recirculated. This was achieved through a bottom-up approach, estimating detailed material requirements for different assets. The analysis is based on the materials needed to retrofit the current building stock from 2023 to 2050, following an accelerated scenario to meet IEA net-zero targets by 2050. The model also calculates the associated carbon abatement from the recirculated materials. Parameters: The model considers four types of assets: residential housing, residential apartments, commercial buildings and industrial buildings. It also considers the components that would be upgraded during a typical retrofit, including insulation, roofing, cladding, ceiling tiles, doors, windows, HVACs, lighting and appliances. Retrofits that change how a building is used (such as turning an office into a hotel) or increase its footprint (such as increasing the number of floors) are excluded from this analysis. Calculations: Average weight is assumed based on the type of asset for retrofit, which is then scaled by the number of retrofits needed to achieve net-zero targets within one year. For each component and asset type, required materials are considered to estimate how much can be recirculated in 2024, 2030 and 2050. Circularity in the Built Environment: Unlocking Opportunities in Retrofits 14