Urban Mining—The city is a stockpile of raw materials for the future circular economy

December 4, 2019

Cities cover only 2% of the earth’s surface, but consume 75% of resources. Take London for example: 125 times the city’s area has to be used to produce resources needed for the city. With a growing world population, this problem will only increase. Gregor Grassl has a solution to this problem: the city as a circular economy.

The city as a circular economy—a holistic approach for a growing world population

Soon, current methods for the production of vital raw materials will no longer be sufficient. The circular economy offers a holistic solution to this problem: It aims to continue doing business, but at the same time to improve the world. When a property is bought today, the building suffers an immense loss in the value of its physical components. Currently, the major factor in real estate price growth is location.

Drees & Sommer aims to change this in the future. It is our goal to generate added value by harvesting a building’s material resources and reusing them for new projects. This approach would transform the buildings in our cities into repositories for raw materials.

Urban Mining
Urban mining is a concept to recycle resources already available in our cities – as part of a circular economy. Photo by Ivan Bandura on Unsplash
„Today, every medium-sized European city contains more copper than an average copper mine.“


Utilizing existing buildings as sources of raw materials would allow us to extract fewer finite natural resources. Instead, reusable resources would be reintroduced into a closed cycle. As with the transition to Smart City, co-creation is extremely important. Smart technology should not only be installed to give a building’s users the best possible experience or to generate meaningful information for its users. We need to use data mining and GIS models to map:

  • which buildings have which materials in which quantities, and
  • when they become available for reuse.

Creating a database of building components makes sustainable dismantling possible—and has enormous market potential

At present, only 1% of the raw materials we use are actively recycled, the remainder are sent for downcycling, incineration or landfill. The dismantling of these raw materials is a vastly underexploited business model with a huge market potential. To make the most of this potential, however, recycling processes need to be optimized and there needs to be innovation in the way we use, structure and combine different materials. This would enable us to reuse existing materials without compromising quality, and at a lower market price.

Buildings already have energy certificates. Gregor Grassl proposes an additional “material passport” to make the recycling economy a reality. Such passports would categorize exactly which materials have been used in which building, thus making sustainable dismantling possible in the future. After all, while a building may not be around forever, the circular economy can ensure that its components are given a new lease on life.

Lisa Kohl

Business Development Manager / Corporate Strategy, Messe München