Heizungsanlagen in Nichtwohngebäuden aus Materialflussperspektive - Dynamik und Bestand am Beispiel der Heizungsleitungen

Heating systems in non-domestic buildings from the perspective of material flow: heating pipes as an example of stock and change.

More than 15 billion tonnes of building materials have been used in German buildings, almost half in non-domestic buildings. These are primarily mineral-based mass-produced building materials which make up the bulk of Germany's overall resource use. The amounts of metals such as steel, copper and aluminium are much smaller, but no less significant in terms of raw material flows. They are found in construction, but are also concentrated in the building services systems such as heating and pipework. Although indicators are available for the amount of metal content in construction, the data for building services has so far proved patchy. This paper presents an assessment of the materials stored in building services systems for non-domestic buildings. Our focus is on pipework for heating systems. Our approach was to combine the calculations for model buildings with an analysis for the materials employed, using databases of buildings, to produce figures for the stock and flows, considering building activity. To date, steel has been the dominant material stored in heating systems for existing buildings, but also in exit flows. However, steel forms a decreasing proportion of the stock, and is being replaced by copper and plastics, which feature heavily in input flows. The present paper states the order of magnitude for the above, and presents this in the context of the debate about managing anthropogenic stores.