MATERIAL-EFFICIENT DESIGN

1.1. DESCRIPTION Material efficiency-oriented design involves adopting design and construction techniques that minimise the production of construction and demolition waste (C&DW), but above all that limit or eliminate the waste of resources, such as energy and water, particularly during the construction phase. This translates into careful design of the different components, but also of the individual construction phases. 1.2. RELEVANCE FOR CIRCULAR BUILDINGS This practice involves acting in the early stages of the life cycle (planning, design, component production and construction) of the building according to the circular economy principles of Reduce, Refuse and Rethink/Redesign: with this design paradigm, material savings are maximised, with even the possibility of using materials derived from recycling and reuse to increase circularity; in addition, as no excessively complex on-site processing is required, the number of vehicles and handling is reduced, with the associated savings in fossil fuels and emissions. The use of off-site manufactured components also reduces the amount of water that is usually required on-site to complete construction operations. 1.3. INNOVATION ASPECTS Compared to traditional design techniques, the aim is to move away from on-site production in favour of off-site realisation of components; this leads to a change in the management of logistics and material storage, favouring a just-in-time approach: this increases the precision with which site schedules must be realised. This design philosophy requires a change of mindset in designers and companies, with a greater inclination towards prefabrication. The extensive use of prefabrication brings about considerable changes in the management of logistics and transport on site, but also in the storage of materials and delivery times.

2.1. PRACTICAL APPLICATIONS - Use of prefabricated components, transported and simply assembled on site - Standardisation-oriented design and optimisation of building parts - Use of optimisation software and models as well as digital technologies for component design - Ad-hoc definition of site configuration - 3D printing of components to avoid material waste - Construction of new buildings or parts of buildings only if extremely necessary and if it is not possible in any way to reuse something already constructed - Drawing up a construction and dismantling plan - Use of self-healing materials to ensure longevity of structures and reduction in the use of new materials - Identification of consolidation centres to facilitate the storage of prefabricated materials, even large ones

3.1. BENEFITS - Reduction of waste produced during construction on site - Simpler and faster work on site, with less waste of energy and water - Optimised structures that are not excessively heavy, simplifying assembly and disassembly operations - Reduced environmental impact in terms of emissions due to optimised use of resources and materials - No need to draw up plans for on-site waste management, including waste separation and the resulting logistics - Reduction of waste in material logistics due to consolidation centres, especially in terms of fuel and packaging 3.2. COMPLEXITIES - Need for experienced professionals able to operate according to multi-parameter optimisation schemes - Problems from the point of view of both transport and on-site storage of prefabricated parts, especially large ones - Much more laborious and complex design phase, characterised by numerous attempts and changes to layouts - Design of the prefabricated modules considering their intersections with the various services - Waste of material originated by necessary changes on site as a result of design errors, which negates the efficiency of prefabrication - Inability to realise overly complex and articulated designs