Construction Materials and Risks to Nature

Nature under pressure

Nature is under pressure. Seven out of nine planetary boundaries have been crossed. Both globally and in the Netherlands, most attention goes to limiting climate change. At the same time, halting biodiversity loss and restoring nature requires at least as much attention.

In the Netherlands, a growing number of construction companies work on nature-inclusive construction. This is a positive development, as it means we take nature at the construction site into account. At the same time, we must also take nature into account in the supply chains of our raw materials.

This exploratory study identifies the nature-related risks associated with the extraction of raw materials for the Dutch construction sector. The analysis covers concrete, steel, asphalt and timber. For this analysis, we applied the Science Based Targets for Nature (SBTN) methodology.

Nature-related risks vary by material and location

Construction requires raw materials. Extracting these raw materials introduces risks to nature, for example through water use in water-scarce areas, nitrogen emissions in areas with high nitrogen concentrations, or a strong presence of threatened species.

The main nature-related risks per material:

• For concrete, the extraction of sand and gravel (e.g. in the Netherlands and Germany) poses high nature-related risks due to water use and biochemical pollution at locations with existing water shortages and high nitrogen concentrations.
• For asphalt, the same risks of water use and biochemical pollution apply to sand and gravel extraction.
• For steel, iron ore and nickel mining in countries including Brazil and Indonesia pose high nature-related risks due to land use and high local ecological integrity.
• For timber, the harvesting of tropical timber poses high nature-related risks, mainly due to the threatened species in tropical forests where timber is harvested.

The environmental impact and nature-related risks of abiotic materials (concrete, steel, asphalt) differ from those of biotic materials (timber). The environmental impact of abiotic materials is generally higher than the impact of bio-based materials. Whereas abiotic raw materials cause environmental impact through energy-intensive production processes, biotic raw materials require land surface to grow.An important consideration is that producing construction materials often causes a greater environmental impact than extracting raw materials. Fossil fuels – both extraction and combustion – are the major cause of this. This results not only in carbon emissions, but often also in biochemical pollution that harms nature.

Three pathways towards nature-inclusive supply chains

We need to broaden our focus from nature-inclusive construction to nature-inclusive supply chains. This requires a combination of three pathways:

1. Designing and building with less (raw) material, as lower material use leads to less raw material extraction, fewer production processes, lower environmental impact and therefore lower nature-related risks. This requires deliberate choices throughout the entire development and construction chain.
2. Accelerated carbon reduction in concrete, steel and asphalt production, as a focus on carbon emissions often results in lower fossil fuel use. This reduces nature-related risks in both extraction and combustion of these fuels – mainly coal.
3. Responsible sourcing and supply chain transparency, to identify and mitigate the risks of virgin materials. In short supply chains (e.g. sand, gravel), origin can often be focused on directly. In longer, more complex supply chains (e.g. iron ore, timber), certification plays a central role.