07.01.2026

Resource Planning Beyond Floor Space—How to Integrate Material Flows

Building design

Urban landscape in harmony with green nature in front of snow-covered Swiss Alps, photographed by Daniele Mason

Anyone who takes urban development seriously can no longer think solely in terms of square meters and plots of land. Resource planning that goes beyond land area requires radically new tools—and the courage to view material flows as an integral part of urban planning. While most municipalities are still struggling with Excel spreadsheets, pioneers are already preparing for the next revolution: cities that understand their material flows, manage them, and consistently design them in line with the principles of a circular economy. Welcome to the age of material-intelligent urbanism!

Resource Planning in Urban Planning: Why a Focus on Area Is No Longer Enough
Material Flows as the Key to Sustainable Urban Development and the Circular Economy
Methods and Digital Tools for Integrating Material Flows into Planning Processes
Best-practice examples from Germany, Austria, and Switzerland
Challenges: Data availability, governance, and organizational upheavals
Relevance for Landscape Architects, Planners, and Local Decision-Makers
The role of urban mining and digital resource registries
Opportunities through new business models, material exchanges, and urban material cycles
Critical reflection: Risks of commercialization, data silos, and social exclusion
Conclusion: Why Material Flows Are the New Gold of the Sustainable City—and How the Profession Should Respond

From Land-Use Planning to Material Flow Management: Why Material Flows Make the Difference

The era when urban planning was synonymous with land-use zoning and parceling is finally over. Anyone who seriously discusses sustainable urban development today must grapple with a new currency: material flows. While land area, as a static quantity, is relatively easy to measure and manage, material flows conceal highly complex, dynamic processes that not only shape cities but also determine their long-term ecological, social, and economic prospects. The focus on resources does not end at property lines, but extends deep into the infrastructures, supply chains, and life cycles of urban systems.

Material flows are the city’s true lifelines. They describe how building materials, energy, water, nutrients, and waste circulate through urban space—ideally in closed loops. But the reality is often quite different: resources are imported, consumed, and then exported again as waste. The linear model of resource use is not only ecologically disastrous but also economically risky, as recent price spikes and supply bottlenecks for raw materials have impressively demonstrated. Cities that do not understand and manage their material flows are fundamentally vulnerable.

This is precisely where resource-based urban planning comes in. It views urban spaces as metabolic systems in which the input, throughput, and output of resources must be made visible and managed. This requires new skills, new tools, and, above all, a new mindset. Anyone who believes that conventional land-use accounting can meet the challenges of the future underestimates the dynamics and complexity of urban material flows—and squanders enormous potential for innovation and sustainability.

Particularly in German-speaking countries, where land consumption and infill development are central political issues, the integration of material flows is often neglected. This is due not only to limited data availability but also to traditional planning paradigms that are difficult to change. Yet the signs of the times are clear: resource efficiency, the circular economy, and urban mining are pushing their way onto the agenda—and turning material flows into a strategic lever for urban planning.

Those who fail to keep pace with this change risk not only environmental deficits but also massive competitive disadvantages. After all, the cities of the future will no longer be judged by how much land they consume, but by how intelligently they manage their resources. The integration of material flows is therefore not just a nice add-on, but a matter of survival for forward-looking municipalities.

Making Material Flows Visible: Methods, Tools, and Digital Innovations

The central challenge in integrating material flows into urban planning is their invisibility. While land areas, parcels, and buildings can be clearly mapped in the cadastral registry, material flows usually remain hidden. They are rarely recorded, let alone systematically analyzed. But digitalization opens up entirely new possibilities here—provided it is used consistently and intelligently.

Digital resource cadastres play a key role here, as they can be used to map the stock of building materials, infrastructure, and even “gray energy” in urban areas. Cities such as Zurich and Vienna are already experimenting with such cadastres, which not only document the quantities and qualities of existing materials but also identify their location, accessibility, and potential for reuse. On this basis, urban material cycles can be closed—for example, by specifically using demolition materials from one neighborhood for new construction in another.

Modern GIS systems, coupled with BIM (Building Information Modeling), make it possible for the first time to track material flows spatially and temporally across the entire life cycle of a building or infrastructure project. In the process, material passports are created that document all relevant properties and reuse options. Innovative tools such as urban mining maps, material exchanges, or digital marketplaces for secondary raw materials address this very issue and create transparency where uncertainty once prevailed.

But that’s not all: artificial intelligence and big data analytics offer the opportunity not only to capture the complexity of urban material flows but also to manage them. Simulations make it possible to run through scenarios for various planning options and estimate the impacts on resource requirements, carbon footprint, and waste disposal costs. In this way, traditional planning transforms into a data-driven control process that can react dynamically to changes.

The biggest hurdle remains access to reliable data. Many municipalities lack the necessary infrastructure or expertise to systematically track material flows. Standards, interfaces, and uniform data foundations are often lacking. This calls for initiatives at the state and federal levels, as well as the courage to foster cooperation between public and private actors. Because one thing is clear: without data, there can be no management—and without management, there can be no genuine resource transition.

Best Practices from the DACH Region: Where Material Flows Are Already Shaping Urban Development

A look at real-world practice shows that there are indeed cities and regions that have long since made material flows a top priority. Pioneers such as Zurich, Vienna, Hamburg, and Basel impressively demonstrate how resource-based urban planning can work—when political will, the right expertise, and innovative tools come together.

Zurich, for example, has ushered in a new era of inventory-taking with its “City Resource Cadastre.” This system systematically records not only traditional building materials but also infrastructure materials such as metals, plastics, and even soil types. The goal: an urban raw materials bank that makes it possible to specifically draw on local resources during demolition or renovation, thereby drastically reducing transportation distances, costs, and emissions. Initial projects show that up to 30 percent of the building materials used in building construction can be sourced from the city’s own inventory—an ecological and economic success story.

In Vienna, meanwhile, as part of the Seestadt Aspern project, a resource management system was implemented from the very beginning that goes beyond traditional construction site logistics. Here, material flows are not only documented but actively managed—from supplier selection and construction site optimization to the reuse of excavated soil and demolition debris. The result: significantly reduced landfill requirements, lower raw material costs, and a measurably better carbon footprint for the entire neighborhood.

With the “Circular City” project, Hamburg is focusing on the close integration of material registries, digital construction site planning, and urban material exchanges. Here, builders, architects, and planners can not only offer and request materials but also transparently trace their origin, quality, and recyclability. This creates a market for secondary raw materials that drives the material cycle and opens up new business models for the construction industry.

Basel, a pioneer in the circular economy for existing buildings, has introduced a digital inventory for all major projects. There, building material flows are evaluated not only from a planning perspective but also from a business management perspective—including life-cycle costs, recycling potential, and carbon footprint. As a result, investors and clients now have, for the first time, a solid basis for decision-making regarding sustainable construction projects that goes far beyond traditional returns on land.

These examples show that material flows are no longer an abstract topic of the future, but rather a tangible management tool for modern urban development. They open up new opportunities for innovation, participation, and economic efficiency—provided one is willing to step outside the comfort zone of traditional planning and embrace a genuine paradigm shift.

Challenges, Risks, and the Role of the Profession: What Needs to Be Done Now

Despite all the successes and innovations, there are numerous obstacles on the path to a material-intelligent city. Integrating material flows into urban planning is not a sure thing; rather, it requires a shift in thinking at all levels—from legislators and government agencies to local planners and landscape architects. Without clear governance, transparent processes, and a willingness to cooperate, the resource transition will remain a patchwork.

A key problem is the lack of standardization in the collection and evaluation of material flows. Different data sources, incompatible software solutions, and proprietary interfaces hinder collaboration and lead to data silos that leave valuable knowledge untapped. There is an urgent need for uniform standards, open interfaces, and a comprehensive data strategy—both nationally and internationally. Only in this way can material flows become transparent, comparable, and manageable.

Another risk lies in the commercialization of urban resource information. If digital material registries and material flow data are controlled exclusively by private platform operators, there is a risk of monopolistic structures and a lack of transparency. This cannot be in the interest of urban development oriented toward the common good. The public sector must therefore take its role as the guarantor of data sovereignty, data protection, and democratic oversight seriously and create the appropriate framework conditions.

The social dimension must not be underestimated either. Material flows are not an end in themselves but must always be considered in the context of quality of life, social participation, and urban equity. Those who focus exclusively on efficiency and cost-effectiveness risk leaving disadvantaged neighborhoods or user groups behind in resource management. Integrated approaches are therefore needed that give equal consideration to ecological, economic, and social goals and enable participation from the very beginning.

For landscape architects, planners, and urban developers, this means they must acquire new skills, think interdisciplinarily, and be prepared to take on new roles. Traditional planning expertise is no longer sufficient. What is needed is systems thinking, data literacy, and the ability not only to analyze complex material flows but also to actively shape them. The profession faces an exciting challenge—and the opportunity to redefine urban development.

Future Prospects: Material Flows as a Driver of Innovation for Sustainable Cities

The outlook for the future is clear: material flows are becoming the benchmark for urban sustainability. Cities that know how to intelligently manage their resource flows will become more resilient, independent, and attractive—for residents, investors, and businesses alike. The integration of material flows not only offers ecological and economic benefits but also opens up new opportunities for innovation, value creation, and cooperation.

Digital tools, AI-powered analyses, and open material exchanges will become standard features of modern urban development in the coming years. They enable not only more precise planning but also dynamic management of resources during day-to-day operations. In this way, the city itself becomes a key player in the circular economy—flexible, adaptive, and forward-looking.

At the same time, new business models are emerging along the value chain of urban building materials. From the recovery of rare metals from infrastructure structures to the reuse of high-quality wood and concrete elements, all the way to digital marketplaces for secondary raw materials—the possibilities are diverse. Those who invest early in the development of such platforms and business models secure a decisive competitive advantage.

The profession of landscape architects and urban planners thus faces a dual challenge: On the one hand, it must help shape the technical, organizational, and legal framework for effective resource management. On the other hand, they are called upon to translate the potential of material-based planning into vibrant, social, and aesthetically sophisticated urban landscapes. Only in this way can the leap from theory to practice—and from vision to reality—be achieved.

Ultimately, the conclusion is simple: Those who ignore material flows are planning without regard for the future. Those who integrate them design cities that are not only beautiful but also smart and sustainable. It is time to rethink resource planning—beyond land area, beyond routines, beyond the comfort zone.

Conclusion: Resource Planning Beyond Land Use—The New Paradigm of Urban Development

Material flows are the new gold of sustainable urban development. They reveal what was previously invisible and open up possibilities that traditional land-use planning could never offer. Those who have the courage to step outside their comfort zone and adopt a holistic approach to resource planning will be rewarded with innovation, participation, and resilience. The examples from Zurich, Vienna, Hamburg, and Basel show that it works—when political will, digital tools, and a new professional identity come together.

The challenges are considerable: a lack of data and standards, organizational barriers, and conflicting social and economic goals. But they are no reason to stand still; rather, they are a call to action. Urban planners, landscape architects, and decision-makers must set the course now—for a city that not only manages its resources but also uses them intelligently and continually reinvents itself.

The future of the city lies beyond land area. It lies in the intelligent management of material flows. Those who adopt this perspective do more than just design buildings and public spaces; they ensure that cities remain vibrant, equitable, and sustainable. It is high time to rethink resource planning—as an integral, creative, and indispensable component of modern urban development. G+L remains at the forefront of this movement—with expertise, passion, and a clear eye for what matters most.

20.01.2025

Design

Sculpture of the month: Stone postcard from Solingen

Building design

Bush knife: The Solingen cutting tool turned stone on the right by the hedge. On the left, an unnamed steel sculpture by Thomas Röthel

Steel products from Solingen, especially knives, are known all over the world. Even in the South American jungle, Bud Spencer warned his partner Terence Hill of a “postcard from Solingen” in his back – i.e. the switchblade in the hand of the sneaking attacker – in the 1973 cinema classic “Two Heavenly Dogs on the Road to Hell”. For the tenth anniversary […]

The Solingen trade fair focuses on the products of local industry, in the classic city of blades, of course, especially the well-known steel products. Directly opposite the venue of this largest trade fair in the Bergisches Land region – the local ice rink – is the premises of Marmor Pauly, which has been working in natural stone since 1871. “A knife doesn’t always have to be made of steel,” thought owner Armin B. Pauly, architect and graduate civil engineer.

And it doesn’t have to be handy either: together with the self-employed stone sculptor Hartmut Hegener, he created a butter knife sculpture on a scale of 10:1 to place in front of the entrance to the trade fair and point out that, in addition to the proud steel tradition, there are also many years of stone masonry activity. The knife measures 2.30 meters with a handle made of polished Anröchter Grünstein, a calcareous sandstone from the Soest region. The finely ground blade made of “Belgian granite”, the Belgian equivalent of Aachen bluestone, was made with ground-in fiberglass reinforcement. The contrast between the darker blade and the lighter handle is enhanced by the different cut, which makes the Belgian bluestone appear particularly dark. For installation, the artwork was anchored on a base stone made of black Swedish in the area of the main entrance.

Art exhibition flanked the trade fair

Because Pauly is a cosmopolitan, art-loving person and the “knife made of natural stone” contains a wink at other materials, an art exhibition with a wide variety of materials was held on his factory premises opposite the trade fair from June 8 – 10, 2018 – in addition to works by sculptors and painters, including steel sculptures by Thomas Röthel and Stephan Mensler. This created a bridge between materials and street sides.

After the event ended, however, the city of Solingen showed no interest in keeping the potential postcard motif in front of the ice rink – so the monstrous knife will soon find a new home with a well-known steelware manufacturer.

12.01.2025

Design

Museum of 1000 Places

Building design

Germany

The Federal Republic of Germany has been commissioning art in architecture for its buildings in Germany and abroad since 1950. Over the decades, around 10,000 works have been created. Natural stone works are also included. Now the Federal Office for Building and Regional Planning (BBR) is making the works of art digitally accessible – via the online platform “Museum of 1000 Places”. In conversation with Dr. Ute […]

Ute Chibidziura: It’s an online presentation for the federal government’s art in construction. In other words, art that is created in connection with construction projects. Since 1950, art in construction has been realized in federal buildings, so that over the years an internationally unique stock of post-war art has been created, which includes the works of many well-known artists in all genres and techniques. We wanted to present this collection of art, which is spread across hundreds of properties in Germany and abroad, in a bundled form.

Many works of art are not accessible to the public …

One peculiarity of art in architecture is that it is tied to the building and is realized in places that are only accessible to a few people for security reasons or, like embassies, are in geographically remote locations. As a result, there are numerous works of art that are little known or have fallen out of sight over the years. With the “Museum of 1000 Places”, we can bring them back into the public eye and make them accessible to the general public.

Why in the form of a virtual collection?

The collection comprises around 10,000 works of art in total. We couldn’t present them in an illustrated book or in an exhibition – that would go beyond any organizational and personnel framework. The “Museum of 1000 Places”, on the other hand, is structured in such a way that works of art can be added bit by bit and the museum grows continuously. In addition, changes can be made to the content at any time. Art in architecture would be difficult to show in a traditional exhibition anyway, because in order to illustrate its location in the spatial context, you would have to build a model of each room or building and prepare picture galleries and texts for it, which would mean an enormous amount of work for just a few examples. Another advantage of a virtual exhibition is that it is not tied to a specific location, but can be viewed from home via the Internet.

How does the digital museum visitor navigate through the site?

There are several ways to access the art: an intuitive one via the images of the artworks on the homepage, a systematic one via the artworks, artists or locations tabs and one via the free text search. Within the artworks, you can sort by technique or context of use.

What information can you find when you call up a work of art?

You will find detailed information about the artwork in its architectural context, about the building and the property, and of course about the artist. It explains the artist’s career, the focus of their work and where else they have realized art on buildings. All information and photos relating to a work of art are stored in the form of a PDF that can be downloaded.

How does the virtual museum build a bridge to the physical world?

The museum indicates whether a work of art is freely accessible or at least open to the public, so that you can also view Kunst am Bau as part of a Sunday stroll. In addition, all works of art will gradually be equipped with a QR code that can be used to link to the “Museum of 1000 Places” to obtain detailed information about the work of art.

Which works of art are made of natural stone?

One important example is the “Rising Phoenix” by Hannes Schulz-Tattenpach on the Old House of Representatives in Bonn. This work of art made of limestone was the first work to be selected and commissioned after the Second World War as part of an open art-in-architecture competition. The phoenix rising from the ashes was intended to refer to the situation of the Federal Republic of Germany at the time, which had to reorganize itself as a democratic state after the war. The motif was still considered so apt in 1974 that it was used as a stamp on a special postcard issued by Deutsche Post to mark the 25th anniversary of the Federal Republic.

You can take a look at the database here: www.museum-der-1000-orte.de.