High-quality reuse of materials in the building sector

Abstract

Waste generation is one of the main environmental problems and is a result of the current linear economy. Materials/elements are used whereafter they are wasted which is a problem considering the finite material supply on earth. Therefore, the current linear economy needs to move towards a circular one in which materials are reused and thus kept in the circle. However, reuse is still not a common practise. This is due to the fact that there are no insights in the structural feasibility, potential savings on environmental impact, and costs related to reuse. Besides the lacking knowledge about the different aspects there is no clear image where the potentials for reuse are located within the sector.
The goal of this research is to give insights in the reuse potentials and to find opportunities within the sector. This research started with a material flow analysis to find promising material flows in the sector. In this material flow analysis it was found that the demolition of office buildings is responsible for a big portion of the outgoing material flow and the majority of the ingoing material flow is related to the new construction of serial houses. In the analysis it was found that the elements with the highest ECI and mass are floor elements. Next the available floor elements coming from office buildings and the floor elements needed for the construction of serial houses were examined to check possible matches. It was found that new plank- and hollow core slab floors used in serial houses can potentially be substituted for reused monolithic- and hollow core slab floors out of office buildings.
Thereafter, two different tools were developed. One related to the reuse of monolithic floors and one related to the reuse of hollow core slab floors. These tools are means to give insights in the reuse potentials considering the structural feasibility, potential savings on environmental impact, and costs. Different cases were checked using the tools and the following results were found:
-In all cases it was structurally feasible to use reused floors coming from office buildings in the new construction of serial houses.
-When reused floor elements are used it is possible to save 40-90% on environmental impact.
-Reused floor elements can be cheaper or more expensive as new floor elements.
These results are promising and hopefully contribute to an acceleration of reuse in practise. The research states where the potentials for reuse are located in the sector and presents two tools which check the reuse potentials considering structural feasibility, environmental impact, and costs.