Towards a multiscale framework for modeling and improving the life cycle environmental performance of built stocks

Abstract

Cities are complex sociotechnical systems, of which buildings and infrastructure assets (built stocks) constitute a critical part. As the main global users of primary energy and emitters of associated greenhouse gases, there is a need for the introduction of measures capable of enhancing the environmental performance of built stocks in cities and mitigating negative externalities such as pollution and greenhouse gas emissions. To date, most environmental modeling and assessment approaches are often fragmented across disciplines and limited in scope, failing to provide a comprehensive evaluation. These approaches tend to focus either on one scale relevant to a discipline (e.g., buildings, roads, parks) or particular environmental flows (e.g., energy, greenhouse emissions). Here, we present a framework aimed at overcoming many of these limitations. By combining life cycle assessment and dynamic modeling using a nested systems theory, this framework provides a more holistic and integrated approach for modeling and improving the environmental performance of built stocks and their occupants, including material stocks and flows, embodied, operational, and mobility‐related environmental flows, as well as cost, and carbon sequestration in materials and green infrastructure. This comprehensive approach enables a very detailed parametrization that supports testing different policy scenarios at a material, element, building, and neighborhood level, and across different environmental flows. We test parts of our modeling framework on a proof‐of‐concept case study neighborhood in Melbourne, Australia, demonstrating its breadth. The proposed modeling framework can enable an advanced assessment of built stocks that enhances our capacity to improve the life cycle environmental performance of cities.

Impact of urbanization on construction material consumption: A global analysis

“…The uncertainties mentioned can be overcome if the building material consumption is calculated according to the bottom‐up principle, using material‐intensity coefficients for typical structures to make projections for specific reference areas (Ortlepp et al., 2015a). Applications can be found at different levels, from neighborhoods, cities, and regions to global perspectives (Pauliuk et al., 2021; Peled & Fishman, 2021; Schiller, 2007; Stephan et al., 2022). An advantage of these approaches is that they provide a high degree of differentiation of materials; the disadvantage is mainly the incomplete representation of material stocks and flows, especially due to gaps in knowledge about the full extent of built structures and their dynamics, the crucial basis for extrapolation.…”

Urban Metabolism: Definition of an Integrated Framework to Assess and Plan Cities and Territories

“…An interesting conceptual framework is the Economy-Wide Material Flow Analysis (EW-MFA) that employs the Drivers-Pressures-Responses logic (as a simplified version of DPSIR tool) and the system dynamics approach between natural and human sides (Cárdenas-Mamani and Perrotti 2022), or even the combination of life cycle approach with dynamical modelling by considering a nested systems theory to support the improvement of building stocks (Stephan et al 2022). GIS-based methods play a transversal role in dealing with complex spatial systems.…”

High-Resolution Mapping of Material Stocks in Belgian Road Infrastructure: Material Efficiency Patterns, Material Recycling Potentials, and Greenhouse Gas Emissions Reduction Opportunities

“…Moreover, the spatial knowledge of materials stocked in road infrastructure will be key for identifying urban mining opportunities, planning investments in primary and secondary operations, anticipating potential logistical constraints of waste collection and processing facilities, and identifying GHG emissions reduction opportunities associated with material-efficient road planning and material recycling all of which will improve waste management and raw material sourcing. 19 With this spatial knowledge, transportation distance of secondary materials from worksites to plants can be accurately estimated, which can help determine the environmental performance and economic feasibility of increasing material circularity in road construction. 20,21 Belgium covers an area of 30,688 km 2 and hosts about 11.5 million people as of 2020.…”

“…Accurate and spatially refined mapping of materials accumulated in road infrastructure can help reveal the elusive patterns of material stock efficiency, delivering important insights on how more efficient spatial configuration can save energy and materials required for building up and maintaining road infrastructure. Moreover, the spatial knowledge of materials stocked in road infrastructure will be key for identifying urban mining opportunities, planning investments in primary and secondary operations, anticipating potential logistical constraints of waste collection and processing facilities, and identifying GHG emissions reduction opportunities associated with material-efficient road planning and material recycling all of which will improve waste management and raw material sourcing . With this spatial knowledge, transportation distance of secondary materials from worksites to plants can be accurately estimated, which can help determine the environmental performance and economic feasibility of increasing material circularity in road construction. , …”