opportunity to generate new resources and local employment based on urban
mining. Behind this will, many challenges arise. Indeed, reaching best environmental performances often relies on many interrelated aspects such as relationships
between: territorial waste management, sorting practices and possible reuse or
improvements of recycled materials’ qualities; existing or innovative treatment
technologies, regulations and standards, and possible markets for future recycled
products; disturbance of markets’ equilibrium by the introduction of recycled
materials and possible avoided environmental impacts; environmental effects of
scale changing from small innovative experience to large territorial applications,
etc. According to local specificities (e.g. regulations, waste management organization) best environmental options may differ. Finding them is finding favorable
combinations of solutions all along the waste treatment chain for sustainable urban
systems, rather than ready-made preconceived ones. Introducing economic, technological, or social mechanisms into LCA calculations provides knowledge that can
be adapted in various contexts.
Five oral presentations were given in the session which focused on innovative
modelling initiatives combining LCA with complex models in order to improve
knowledge for more sustainable urban construction waste management.
2 Prospective and Regional Modelling of Construction
Material Flows
The session started with a presentation from Niko Heeren [1] providing an overview of a bottom-up dynamic MFA model he developped and applied for
Switzerland, and the relevance of construction material flows for the environmental
impact of buildings. Future possible scenarios were compared and potentials for
closed loop recycling analysed [1]. The development is based on a GIS-based
building stock model to determine material flow of the Swiss building stock. By
merging a national building register with a three-dimensional dataset, it is possible
to quantify the material volumes for all residential buildings. In order to perform a
prospective assessment, element and building service life are determined using a
stochastic approach. Therefore, the model accounts for the dynamics due to material
dwelling time. Life cycle assessment is used to assess the environmental impacts of
future material flow.
206
A. Ventura and M. Trocmé
mining. Behind this will, many challenges arise. Indeed, reaching best environmental performances often relies on many interrelated aspects such as relationships
between: territorial waste management, sorting practices and possible reuse or
improvements of recycled materials’ qualities; existing or innovative treatment
technologies, regulations and standards, and possible markets for future recycled
products; disturbance of markets’ equilibrium by the introduction of recycled
materials and possible avoided environmental impacts; environmental effects of
scale changing from small innovative experience to large territorial applications,
etc. According to local specificities (e.g. regulations, waste management organization) best environmental options may differ. Finding them is finding favorable
combinations of solutions all along the waste treatment chain for sustainable urban
systems, rather than ready-made preconceived ones. Introducing economic, technological, or social mechanisms into LCA calculations provides knowledge that can
be adapted in various contexts.
Five oral presentations were given in the session which focused on innovative
modelling initiatives combining LCA with complex models in order to improve
knowledge for more sustainable urban construction waste management.
2 Prospective and Regional Modelling of Construction
Material Flows
The session started with a presentation from Niko Heeren [1] providing an overview of a bottom-up dynamic MFA model he developped and applied for
Switzerland, and the relevance of construction material flows for the environmental
impact of buildings. Future possible scenarios were compared and potentials for
closed loop recycling analysed [1]. The development is based on a GIS-based
building stock model to determine material flow of the Swiss building stock. By
merging a national building register with a three-dimensional dataset, it is possible
to quantify the material volumes for all residential buildings. In order to perform a
prospective assessment, element and building service life are determined using a
stochastic approach. Therefore, the model accounts for the dynamics due to material
dwelling time. Life cycle assessment is used to assess the environmental impacts of
future material flow.
206
A. Ventura and M. Trocmé