CO2NSTRUCT aims to redesign the linear framework of climate mitigation models by focusing on one section of the economy/market: the construction industry. By focusing on 6 pervasive and/or carbon-intensive construction materials, we map the complete value chains of cement, steel, brick, glass, wood, and insulation materials. Because there are several sub-classes of materials within the 6 chosen materials, we had to divide the materials further into 12 subclasses, doubling the effort for all subsequent tasks in WP1, WP3, and WP5. So far, we have organized data in subcategories but have yet to reach a beta version of the database (milestone 1, WP1). We have revised circular economy practices for 6 of the 12 subclasses of materials, validated by the UB, and provided the supply chain mapping of 8 sub-classes (Steel, CEM 1, Steel, Glass/Stone Wool and EPS, Sawn Wood) of 8 sub-classes (Flat Glass, Brick, Steel, CEM 1, Glass Wool-Stone Wool-EPS, Wood) (milestone 5, WP3). Redesigning the energy-climate mitigation model TIMES framework requires several iterations of the concept. For this, we needed to identify buildings (Cluster 1) and offshore (cluster 2) CE practices and redesign the building industry within the TIMES model. This requires extra effort from WP1, WP3, and an early start of WP5. A key aspect contributing to the definition of scenarios that the TIMES model and framework will consider was identifying policies that bridge climate mitigation and circular economy (Task 2.4) and formulating the citizen behaviour survey (milestone 3, WP2). To map current practices in the development of stakeholders focused on CE analysis, an expert web survey is conducted, considering various assessment frameworks. Furthermore, a database of CE experts is compiled (Task 5.1). The objective of this survey is to identify discrepancies between research findings (Task 3.2) and current practices. Additionally, it aims to provide input to the TIMES model by defining the most representative circular climate mitigation scenarios (Task 6.1) and outlining strategies for their integration (Task 6.2).