The construction and use of our built environment has a considerable environmental footprint. Much attention is given to the reducing the energy use of buildings through intelligent design and zero carbon buildings are not far from becoming a mainstream feature. Energy use in buildings is only one element of a closed loop system when considering building design.
The use of building materials is associated with a range of significant impacts and striving to closed loop systems with regard to this aspect of building design and construction is essential in any aspiration around contributing to a circular economy. Developing an advanced materials strategy is a must and should revolve around the following three elements:
- Reducing the need for materials
- Reducing the need for future alterations to the material fabric
- Selecting appropriate materials
Reducing the need for materials
Avoiding the use of materials is the first and obvious step in any strategy that leads to a closed loop system. The easiest wins regarding the reduction of material use are with the avoidance of waste arisings. Actions that lead to designing out waste are key in this, as is the use of best practice in material management on site. WRAP has produced many resources on designing out waste and anyone with an interest in the topic should review the wealth of information this organisation provides.
Further opportunities to reduce material use lie in considering the materials efficiency of the design. This does not focus on reduction of waste arisings per se, but focuses on minimising the materials demand of both structures and finishes.
Reducing the need for future alterations
Refurbishments and renovations are notorious for their waste arisings. It is inherent to long-lasting buildings that refurbishments occur, but action can be taken to minimise the need for this. This can be achieved by the careful and thorough consideration of how the building will be used and how the design accommodates this. Consideration should also be given to the evolution of use patterns throughout the lifetime of the building or even complete changes in function.
These consideration around particularly challenging for speculative building and it is even more important to pay attention to material use in this scenario.
Wear and tear of buildings as well as accidental damage can be another source of increased material use. Attention to durability and protection from damage can lead to very effective measures.
Selecting appropriate materials
Whilst the reduction of material use is the most effective way of eliminating some impacts associated with material use, paying attention on the life cycle impact of materials that will be used is the final element in good materials strategy. Re-using materials or using recycled materials are of course priorities. For new materials tools such as the BRE’s Green Guide to Specification are a useful first step to minimise impacts, but for a truly closed loop system this should rapidly evolve to the detailed consideration of the actual supply chain of the materials that are used.