The construction industry is one of the biggest and most active sectors of the European Union (EU), consuming more raw materials and energy than any other economic activity. Furthermore, construction waste is the commonest waste produced in the EU. Current EU legislation sets out to implement construction and demolition waste (CDW) prevention and recycling measures. However it lacks tools to accelerate the development of a sector as bound by tradition as the building industry. The main objective of the present study was to determine indicators to estimate the amount of CDW generated on site both globally and by waste stream. CDW generation was estimated for six specific sectors: new residential construction, new non-residential construction, residential demolition, non-residential demolition, residential refurbishment, and non-residential refurbishment. The data needed to develop the indicators was collected through an exhaustive survey of previous international studies. The indicators determined suggest that the average composition of waste generated on site is mostly concrete and ceramic materials. Specifically for new residential and new non-residential construction the production of concrete waste in buildings with a reinforced concrete structure lies between 17.8 and 32.9 kg m⁻² and between 18.3 and 40.1 kg m⁻², respectively. For the residential and non-residential demolition sectors the production of this waste stream in buildings with a reinforced concrete structure varies from 492 to 840 kg m⁻² and from 401 to 768 kg/m⁻², respectively. For the residential and non-residential refurbishment sectors the production of concrete waste in buildings lies between 18.9 and 45.9 kg/m⁻² and between 18.9 and 191.2 kg/m⁻², respectively.

Purpose: To present a comparative life cycle assessment (LCA) of natural and recycled coarse aggregates used in concrete production. Methods: LCA was used to compare the environmental impacts of three alternative of procurement of coarse aggregates for concrete production: extraction and processing of natural aggregates; recycling of demolished concrete either using a fixed or a mobile plant. Site-specific data supplied by companies were used to model the life cycle of these aggregates. A sensitivity analysis was also made for the critical stages of these three life cycles. Results and conclusion: This paper presents and analyses innovative LCA data of production of coarse aggregates, both natural and recycled (from mobile or fixed recycling plants). The recycling process of aggregates has to be optimised, following a selective demolition of buildings that maximises waste recovery, reuse and recycling. The use of these aggregates in the production of concrete is more favourable than natural aggregates only in terms of land use and respiratory inorganics, but coarse recycled aggregates can present a better environmental performance than natural ones if fine recycled aggregates are also used in concrete production instead of being sent to a landfill. These results are, however, very sensitive to the transportation distances.

The health system’s response to the COVID-19 pandemic has involved research into diagnoses and vaccines, but primarily it has required specific treatments, facilities and equipment, together with the control of individual behaviour and a period of collective confinement. The aim of this particular research, therefore, is to discover whether COVID-19 is capable of changing the built environment (BE) and leveraging specific solutions for sustainable buildings or urban areas. Some historical reviews of infectious pandemics have highlighted the development of new solutions in the BE as an additional contribution towards preventing the spread of infection. The BE has an important role to play in supporting public health measures and reducing the risk of infections. The review of potential COVID-19 measures shows the existence of well-referenced solutions, ranging from incremental alterations (organisation of spaces, erection of physical barriers) to structural alterations (windows, balconies) with different timeframes and scales (ranging from changes in building materials to the design of urban areas). A critical exploratory assessment makes it possible to identify measures that may help not only to reduce the risk of COVID-19 transmission (or even prevent it), but also to increase resilience, improve air quality and lower energy requirements or the use of materials, and thus potentially increase the sustainability of the BE. COVID-19 measures challenge us to rethink buildings and urban areas and potentially leverage sustainable BE solutions with win-win outcomes (minimalist design and other solutions). The specific composition of this set of measures must, however, be further researched.