*Article* **Basic Research of Material Properties of Mycelium-Based Composites**

**Hana Vašatko \* , Lukas Gosch, Julian Jauk and Milena Stavric**

Faculty of Architecture, Institute of Architecture and Media, Graz University of Technology, 8010 Graz, Austria; lukas.gosch@tugraz.at (L.G.); julian.jauk@tugraz.at (J.J.); mstavric@tugraz.at (M.S.)

**\*** Correspondence: vasatko@tugraz.at

**Abstract:** The subject of this research is growing mycelium-based composites and exploring their basic material properties. Since the building industry is responsible for a large amount of annual CO<sup>2</sup> emissions, rethinking building materials is an important task for future practices. Using such composites is a carbon-neutral strategy that offers alternatives to conventional building materials. Yet, in order to become competitive, their basic research is still needed. In order to create mycelium-based composites, it was necessary to establish a sterile work environment and develop shaping procedures for objects on a scale of architectural building elements. The composite material exhibited qualities that make it suitable for compression-only structures, temporary assemblies, and acoustic and thermal insulation. The methodology includes evaluating several substrates, focused on beech sawdust, with two mycelium strains (*Pleurotus ostreatus* and *Ganoderma lucidum*), density calculations, compression tests, three-point flexural tests and capillary water absorption. The results of this study are presented through graphical and numerical values comparing material and mechanical properties. This study established a database for succeeding investigations and for defining the potentials and limitations of this material. Furthermore, future applications and relevant examinations have been addressed.

**Keywords:** mycelium; growth; bio-composites; mechanical properties; architecture; materials science
