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View on Value Added Chain and Material Cycles in the Construction Industry

(Innovative) potential of recycling schemes in the construction industry to increase raw materials productivity

Seed funded research project by the Research School at HafenCity University Hamburg.


Co-operation of research:

Univ.-Prof. Dipl.-Ing. Reinhold Johrendt (Building Economics + Construction Management) more...
Prof. Dr.-Ing. habil. Wolfgang Willkomm
(Building Material + Building Construction) more...



Lars Siebels


S.I.M.P.L.E.  |  Sustainable Impacts on Materials and Products, their Lifecycles and Economies

In an interdisciplinary research collaboration by HCU Reinhold Johrendt, professor of Building Economics (Architecture), and Wolfgang Willkomm, professor of Building Material (REAP) both developed a holistic and conceptual approach to economical and ecological recycling of building materials. The aim of this research collaboration is to locate monetary and material synergies in material flows and their value chains in order to analyse them through scientific study and optimise them in reality.

Building economics as a discipline of architecture, planning and overseeing the use of resources, finds itself as a mediator between sustainability, aesthetics, and cost. To a large extent this contributes for the protection for the recourses available to future generations. In many considerations and approaches to the development of sustainable solutions it is often forgotten that funds also constitute a limited resource in our modern society. The construction process and the entire life cycle of a property is an ongoing transfer of cash and raw materials into fixed assets. This value chain is currently running in many stages of the development of a property. At the end of the life cycle, contrary to a sustainable substance flow, it needs funds to dispose of and buy new raw materials and resources. This dependance on the world market can and possibly will impact resource-poor countries such as Germany  and its national construction costs and procedures.

To use raw materials and resources multiple times in an efficient and responsible way the field of building material technology increasingly concerned itself with circulation analyses of individual components of the whole recycling chain of building materials. Circulatory and materials flow analyses clearly show that the potentials of to the construction industry in relation to the use of secondary raw materials at the same label are currently by no means exploited.

Our considerations start with the preliminary choice of materials and end in the planning of dismantling or demolition of a property and the subsequent re-use or recycling of construction materials or products. 


The research is based on parallel considerations of the material flow through co-products and secondary raw-materials to the value chain, all of which results in pioneering ways to optimise the circulation of construction products as a means of increasing resource productivity. The federal government also call for a move towards the multiple usage of resources and an increase of secondary raw materials in the materials used to improve the security of supply in Germany and the EU with raw materials (urban mining) and to regulate market pricing.


Primarily, the focus of our research is on the development of control mechanisms which provide an impetus for the construction and building industry in order to accelerate sustainable development in the areas of raw material consumption and waste recycling to optimise the metarial cycles through alternative mechanisms. With focus on existing systems, a portfolio of recycling strategies for existing and new buildings has been developed. Waste products (components) and waste materials (construction materials) should lead as secondary raw materials back into a circuit to increase the resrouce productivity of the construction industry, e.g. as required by the Progress Report of the National Sustainable Development Stretegy (Federal Government, 2011). The resulting “return system for building materials, construction materials and components” shall be regulated by a yet to be developed and implemented regulation on service models in free competition. Further research goals are the systemization and quantification of the materials used by the construction industry and of the resources contained in the infrastructure and the analysis of material flows and the value chains (monetary values) in the construction industry from design to demolition.


This research project has initially been funded by the HCU under the direction of Prof. Reinhold Johrendt, to draft and submit eligible funding applications. The research cooperation as well as the Research School of the HCU believe that by merging professional expertise in Construction Economics and Building Materials, an interdisciplinary approach and the use of synergies in the field of research can be achieved. Via the International Doctorate Network “construction and property in its life cycle” (www.dokwerk.net) cooperation partners joined 11 other professors at 10 universities across Europe to discuss and work on integral, sustainable  issues regarding the interactions between economical, ecological, and socio-cultural aspects, and to investigate aspects of the entire life cycle of a property.


Using this approach, all cooperation partners build on successfully completed projects in their own field of study. Together they further develop their focus of research on an interdisciplinary level. On the other hand, students of the HCU can get first insights into ongoing research by taking part in the new seminar “Introduction to Sustainable Construction”, wich addresses current topics of economical and ecological approaches in architecture and planning.


Contact: Lars.Siebels(at)hcu-hamburg.de
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