This section deals with material stock. It is very different from the flow data that you have dealt with so far. The video introduces the topic and the sections on construction and biomass explain which and how the data can be found.

Outline of the video

  • Material stock: very different from what we have been discussing before
  • What is material stock: something that sits in the city for a long period of time, generally longer than a year. They also have an environmental impact.
  • Either produced in the city, or comes in as a flow and stays. After some time it leaves the city as a flow again.
  • built infrastructure: buildings, roads, railroads, pipes; electronics, vehicles; biomass: livestock, wood, stored grain;
  • It should be part of the economic system. We don't collect info on birds for example.
  • M6:52, types, summary of what we are interested in
    • Buildings
    • Roads
    • Vehicles
    • Biomass
    • Other specific products/materials present > 1 year
  • M7:30, relevance, why do we care about this
    • Stocks&flows are interwoven
    • Holistic understanding
    • Urban mining
  • M9:25, what to look for?
    • Quantity (weight);
      • but sometimes you will only find number of something or length (e.g. road network)
    • Material composition
    • Age
      • How old
      • What is expected lifetime
    • Growth
      • Get data for a number of years
      • Or get an idea at which rate this is growing
  • M11:13, types of information
    • Building stock
      • Building-based shapefile
      • Total built footprint (surface area)
      • Building details (height, number of floors, materials used, age, etc.)
      • Studies (building types, specific materials, etc.)
      • Data on number of buildings, locations etc.
      • Bill of materials for key infrastructure (used by architects as an input list for buildings)
    • Vehicles
      • Vehicle count
    • Biomass
      • Animals (livestock)
      • Trees
    • Material stock
      • Studies
  • M13:46, examples
    • Nickel-Cadmium batteries in Cape Town
    • Copper in use, in Cape Town
    • Number of registered vehicles per province
    • "Prospecting the urban mine Amsterdam" PUMA study
    • Spatial datasets of Cape Town
  • M17:36, Sources
    • Cadastre
    • Vehicle registration agency
    • Local government reports
    • Google Scholar
    • Keywords: building footprint, building types, vehicle count


The work that accompanies this section is for you to try and find as much information as you can on the stock of the 11 construction materials and add those to the sublayers of 3.4 Stock with the usual upload and tagging procedure.

Try to determine the material that already “sits” in your city, the stock (any material that has been there for longer than a year), no matter how old it is. For the majority of the materials, their stock likely takes place for buildings, but be sure to also think about their use in other urban infrastructure such as roads, bridges, tunnels etc. Ideally, you follow the information search as it was presented in the video and find:

  • building-based shapefile, showing the building footprints
  • Number of buildings;
    • Cadaster data is a great way to start;
  • Overview of infrastructure typologies and building archetypes that exist
  • Material composition per infrastructure typology
  • Number of buildings per typology (for instance, residential, office, apartment buildings, etc.).
  • Optional: material typologies mapped per city (shapefile)
    • You can find these as part of a material stock study for your city.
  • Bill of materials per key infrastructure typologies (used by architects/construction companies, as an input list for buildings)

Sidenote: As you are looking for and finding this information, you may come across demolition plans as well. You can hold on to those and use them for the waste part.


The work that accompanies this section is for you to try and find as much information as you can on the stock of the 12 biomass materials and add those to the sublayers of 3.4 Stock with the usual upload and tagging procedure.

For biomass, the stock is limited to the stock of animals (livestock) and trees, since only these stay for over a year in the system. If you haven’t already found this data in the extraction layer, you can look for it now.

  • Livestock, number of the various animals (also referred to as heads)
  • Trees, number of and kinds of trees in your city; oftentimes there are maps too, but that is a bonus. >>> Check out the video below for more info

Outline of the video

  • Not interested in historic tree cover, but what is there now?
  • Within boundaries, account for trees that are there.
  • Helpful to know for urban heat island effect, air quality and for source of wood.
  • From M3:47, what to look for: tree map, tree inventory (knowing how many and e.g. species), any report
  • From M5:30, examples
  • If there is no info, it is also valuable to add that there is no source of information, some proof, e.g. newspaper article
  • Sources