and final disposal. In the BP scenario, the reuse of ceiling tiles, wooden doors and
stairs, gypsum walls, and metal beams are win-win situations, compared to the
treatments in the BAU scenario, which are more expensive and more pollutant. In
both scenarios, the metal beams are the largest contributors to the environmental
burden. If metal beams are reused, the cost of onsite construction of a new building
drops dramatically. The overall BP scenario is cheaper than the BAU scenario. As
further recommendations, the impact of waste management of each material flow
can considerably decrease by shortening the transport distances. Selective dismantling and demolition, and the reuse of components should be promoted by
including a phase prior to dismantling, in which reusable components and materials
are inventoried and potential buyers are contacted.
7 Conclusions
The whole session showed that the construction and demolition waste (C&D waste)
management is a complex system to be modelled because several types of information must be considered and collected at different scales: at material, building
and processes levels, defining the possibilities in terms of technical valorisation,
and at regional level in order to consider regulations and urban planning policies.
The temporal aspects are also crucial because today’s decisions on construction
engage consequences for the next 100 years, therefore with some potential
important repercussion for the waste management system despite its strong inertia
to changes. All participants agreed that re-use or recycling mass performance is a
weak and unsufficient indicator for assessing waste management systems. There is
an important need for better characterizing stocks, to predict nature and quality of
output flows. Geospatialized data combined with Material Flow Analysis was the
methodology identified and used by the research community. Predictions are based
on scenarios comparison, mainly comparing recycling technologies and possible
substituted materials. However, the link between sorting processes and quality of
output material is not enough investigated, and possible changes in building design
methods that are expected to avoid waste by favoring better adaptability of
buildings should also be investigated. It should support the assessment of waste
prevention strategies efficiency. Finally, including economic market mechanisms,
making the link with availability of material flows responding to the future materials demand would also be relevant in the framework of the sustainable assessment
of C&D waste management.
Management of Construction Waste: LCA …
209
stairs, gypsum walls, and metal beams are win-win situations, compared to the
treatments in the BAU scenario, which are more expensive and more pollutant. In
both scenarios, the metal beams are the largest contributors to the environmental
burden. If metal beams are reused, the cost of onsite construction of a new building
drops dramatically. The overall BP scenario is cheaper than the BAU scenario. As
further recommendations, the impact of waste management of each material flow
can considerably decrease by shortening the transport distances. Selective dismantling and demolition, and the reuse of components should be promoted by
including a phase prior to dismantling, in which reusable components and materials
are inventoried and potential buyers are contacted.
7 Conclusions
The whole session showed that the construction and demolition waste (C&D waste)
management is a complex system to be modelled because several types of information must be considered and collected at different scales: at material, building
and processes levels, defining the possibilities in terms of technical valorisation,
and at regional level in order to consider regulations and urban planning policies.
The temporal aspects are also crucial because today’s decisions on construction
engage consequences for the next 100 years, therefore with some potential
important repercussion for the waste management system despite its strong inertia
to changes. All participants agreed that re-use or recycling mass performance is a
weak and unsufficient indicator for assessing waste management systems. There is
an important need for better characterizing stocks, to predict nature and quality of
output flows. Geospatialized data combined with Material Flow Analysis was the
methodology identified and used by the research community. Predictions are based
on scenarios comparison, mainly comparing recycling technologies and possible
substituted materials. However, the link between sorting processes and quality of
output material is not enough investigated, and possible changes in building design
methods that are expected to avoid waste by favoring better adaptability of
buildings should also be investigated. It should support the assessment of waste
prevention strategies efficiency. Finally, including economic market mechanisms,
making the link with availability of material flows responding to the future materials demand would also be relevant in the framework of the sustainable assessment
of C&D waste management.
Management of Construction Waste: LCA …
209