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Cities play a pivotal role in climate protection. By embracing a circular construction model, they can conserve resources and cut emissions.

Strategies like urban mining, reuse and digital material databases can advance sustainable urban development, but regulation, economic efficiency and a lack of data make progress difficult. While the EU taxonomy and successful initiatives across Europe are creating promising momentum, building a true circular city requires collaboration, appropriate infrastructure and a cultural shift. To build a resilient and vibrant future, cities must lead through strategic planning, active promotion and meaningful collaboration.  

Drivers of emissions – and solutions

In view of growing environmental crises and increasingly scarce resources, the concept of the circular city is becoming increasingly important. Although cities occupy and currently house 58% of the world’s population – a figure projected to . Cities are therefore dependent on large amounts of physical, chemical and biological resources and are a key contributor to climate change. Yet, their autonomy in urban planning and potential for engaging local communities make them powerful platforms for driving scalable, impactful solutions. Cities are drivers of climate change, yet at the same time, they play a key role in mitigating it. Especially in the construction sector, one of the most resource-intensive economic sectors responsible for 34% of global greenhouse gas emissions, the shift to circular principles offers enormous potential. For decades, the linear model shaped the construction sector: raw materials were mined, materials were produced, buildings were erected and finally the demolished materials disposed of. This system results in excessive waste, inefficient resource use and high emissions, bringing the circular economy into focus as a viable alternative.

Materials should be kept in circulation for as long as possible, buildings should be thought of as material banks and dismantling instead of demolition should be at the forefront of planning. According to a , applying circular principles to the construction sector, could significantly cut emissions, 75% of grey emissions, i.e. greenhouse gas emissions that occur during the life cycle of products and buildings and do not come directly from the company, could be saved in construction with reused and recycled materials compared to new construction.

What does circular construction mean and what role do cities play in it?

A circular city applies regenerative principles across materials, energy, water, biodiversity and urban culture. In construction, the focus mainly lies on building materials as resource reservoirs. Keeping products and materials in circulation reduces the need for virgin materials and minimises greenhouse gas emissions. If we look at the circular economy not only limited to materials as resources, but as a systemic approach at the city level, we see its impact on the economy, society, health and well-being.

The flow of materials and energy through a city must become a measurable design parameter through which material flows need to be tracked and material pathways understood via material flow mapping. Reliable, consistent data will be the key to unlocking this understanding of material availability in a city. City governments also play a central role in managing permits, zoning and land-use decisions that directly shape the built environment.

Three approaches are key for circular construction at the city scale:

Urban mining: Cities are considered future material banks. Urban mining involves extracting valuable materials (like metals, concrete, and wood) from existing infrastructure and repurposing them. This reduces dependence on virgin resources and build resources. To facilitate this, a redefinition of value is necessary in the way we view waste building materials.

Design for deconstruction: Instead of demolition, buildings are viewed as modular systems. Materials should be recoverable and reused post-deconstruction, which shifts design paradigms towards adaptability and reversibility. Demolition needs to be held to the same sustainability standards as construction, with a top-down approach of taxes and incentives leveraged to remove waste.

Data: Digital material passports and pre-demolition audits document the condition and type of materials within buildings, paving the way for high-quality reuse. These tools support designers, planners and policy makers in tracking material flows across the urban landscape. Pre-demolition audits help to take stock of the materials present in the building and their condition. Buildings that are yet to be constructed should have material passports built into the construction information. It is also important for cities to track material flows more holistically, monitoring what materials are available, where they are located, and when they become accessible. This can help identify opportunities and unlock potential throughout the urban system. 

The multidimensional value of circular cities

Circular cities generate multidimensional value by fostering economic resilience, enhancing social equity, improving environmental sustainability, and promoting long-term health and well-being.

Economic benefits: The circular economy fosters job creation. According to , half a million people in London will be working in the circular economy by 2030. Jobs in this sector are emerging at start-ups, software operators, service providers and consulting firms, and material banks (both physical and digital). In addition, there will be a shift in the way the industry works. Demolition contractors will see a major rework to their processes, as selective dismantling becomes more important, and the traditional way of demolishing buildings to landfill becomes redundant. New job profiles and further training opportunities in the field of circular construction will also strengthen skills and open prospects.

Social impacts: Reusing materials promotes healthier environments: reduced air pollution, quieter construction phases and better indoor air quality. Since pollution disproportionately affects people living in low- and middle-income countries, the circular model will not only become more sustainable, but also more socially just.

Regulatory leverage: European regulations and initiatives increasingly support the transition to circular cities. At the EU level, the Circular Cities and Regions Initiative offers technical and financial support to local authorities, promoting systemic circular solutions and stakeholder collaboration. Locally, cities like Amsterdam and London are leading by example. Amsterdam allocates public building plots only to projects that follow circular principles. London’s Circular Economy Statement Guidance, within the London Plan, requires major developments to include statements detailing how materials will be reused, recycled, and retained. Despite these advances, regulatory approaches remain uneven across Europe. While some cities have adopted strong local policies, others are in early stages. Greater harmonisation is needed to fully realise the potential of circular cities.

Tools for a circular transformation

The transition to a circular city requires both physical and digital infrastructure. Physical infrastructure refers to the tangible, built structures and facilities for storing and managing materials, while digital infrastructure encompasses the networks, technologies and systems that facilitate communication, information processing and data exchange.

Digital infrastructure, such as platforms aggregating material data, helps match demolition outputs with new construction needs. It is necessary to have accessible data in cities to facilitate these banks, using systems thinking to actively analyse and quantify waste streams, developing material tracking and asset registers, material libraries and databases. Various providers of digital material databases already facilitate the exchange of reusable materials. However, only a centralised recording of new construction, demolition and renovation projects – ideally managed by the city – can unlock synergies and reveal hidden potentials. Alongside digital infrastructure, physical infrastructure forms the backbone of circular construction logistics, such as hubs for material storage and redistribution, modular construction facilities and adaptive reuse of existing buildings – ensuring that circular principles are embedded in the built environment.

Policy and city governance are essential to transformative change – cities must act now to embed circular principles in their planning, construction and economic systems. Regulation, education and infrastructure should align to foster systemic transformation. However, circular cities have been shown to thrive when communities, innovators and stakeholders collaborate.

Progress hinges on:

• Stronger legislative frameworks
• Transparent material tracking
• Investment in reuse infrastructure
• Public awareness campaigns
• Bottom-up networks supporting innovation

As cities navigate climate pressures, embracing circularity offers not only reduced emissions but also more resilient, equitable and vibrant urban life.

Only through decisive action and systemic thinking can cities overcome resource scarcity and pollution and design liveable, sustainable cities. They must actively shape circularity and lead the way as role models for sustainable development