Report: Biobased Materials Lag in Circular Building

The Dutch government's goal for a fully circular economy by 2050 places the construction industry, which accounts for half of the country's resource use, under significant pressure. This ambition is detailed in the national 'Circular Construction Economy' transition agenda, which is part of a broader plan to halve the use of primary resources like minerals, metals, and fossil fuels by 2030. Despite these goals, biobased materials currently see limited use in the Dutch construction sector, with wood comprising only 2% of materials used and other biobased materials a mere 0.1%. The Netherlands Environmental Assessment Agency's most recent report indicates that without additional measures, the 2030 circularity targets are out of reach, highlighting the urgency for scaling up alternatives to concrete and steel. To bridge this gap, the Netherlands Enterprise Agency (RVO) is actively stimulating innovation through challenges with budgets up to €1.8 million, encouraging the use of Dutch-grown crops like hemp and flax to develop building materials. This aligns with research by organizations like TNO, which is exploring the use of the 50,000 tonnes of residual waste from tomato and bell pepper plants for construction materials. A key instrument being advanced in the Netherlands is the digital material passport, with platforms like Madaster creating a public online library for materials used in the built environment. These passports document the origin, quality, and location of materials, simplifying reuse and providing insight into a building's circularity score; the Dutch government is considering making them mandatory for new constructions. This national push is reinforced by the European Green Deal, which mandates stricter environmental performance and circular economy principles for construction across the EU. Regulations such as the Corporate Sustainability Reporting Directive (CSRD) and the Eco-Design for Sustainable Products Regulation (ESPR) are increasing legislative pressure on architects and engineers to specify durable, low-carbon, and repairable materials. Challenges to widespread adoption remain, including the need for large-scale prefab factories, the high initial costs, and the difficulty in obtaining certification for new materials. As long as large-scale production is not established, it's difficult for innovators to compete with the established supply chains for traditional fossil-based materials.