Summary The objective of this project was to illustrate the value of nature-based circularity by illustrating its potential in creating composed and engineered circular products at large, and that of Mycelium-based sandwich panels as perfect embodiment of such product in specific. To effectively explore the feasibility of these panels as a natural and circular alternative, an industry-oriented product development approach was used. Therefore, this research focussed on parameters thought to be crucial in generating interest from industry players. Within the limitation of the research these were the structural behaviour and scaled production of the product. In an extensive analysis of this novel material both general characteristics as exact properties of Mycelium-Based Composites (MBCs) were explored. This project succeeded in getting a ‘feel’ for it and has applied that deeper understanding in tackling the further steps in the research. A potentially promising industry niche was found in the distribution centre construction sector and its dynamics were studied. It was found that this niche sector is extremely sustainability-savvy, accounting for a total share of 16% of all BREEAM certification issued in 2018. While at the same time being responsible for 16% of the nation rigid foam insulation demand. This large quantity simply applied fossil-fuel derived foam was identified as ideal low bearing, ‘positive impact’, fruit. Through interviews with industry experts and an industry analysis several quantitative and qualitative boundary conditions was collected that formed a foundation for the remaining research. It was decided to perform a number of 4-point bend test, exploring the fungal sandwich panel’s potential to serve as roof plate. Both lose MBC as sandwich panel samples were tested. Based on the data provide by the experiments could be concluded both the properties of the material and the product are currently insufficient for the envisioned application. However, the found result were of an order of magnitude interring enough for further research. The MBC is approximately two to three times weaker than traditional foams. Although, the sandwich samples showed ten times better behaviour its full potential was far from realised. Weak adhesion of the individual components and the following premature delamination were identified as the main cause for this underperformance.Summary | 7 Further development is needed on a material, product and application level to achieve applicability, suggestions of potential fruitful development directions have been made. The order of magnitude of the results is however of such comparable quantity that, especially less demanding, employments of the product can on a short-term be accomplished. It is therefore interesting to see that this research has shown how the production process of mycelium-based sandwich panels could look like. By converting button mushroom facilities, a batch-based production system could be put into place with a scale adequate for the demands from the distribution centre construction industry. Twelve of the envisioned facilities could produce all insulation material for the complete sector. In this explorative project it has been shown that this nature-based technology holds potential. Sandwich panels can be made with a certain quality and quantity. But although current product performance is not sufficient for the studied application other widespread uses can be foreseen. So, although further research is certainly needed in the development of composed mycelium-based circular products it can be concluded that based on qualitative and quantitative benchmarks these products can and likely will serve as a sustainable and circular alternative to traditional, oil-based, rigid insulation products.