On Mycoboscus: Design Strategies & Epistemology of a Novel Sustainable Craft

With the advent of mycelium-based composites, we see the emergence of a novel material class. In excess of a technical description, this is a craft in budding. I call it that of mycoboscus.
Originating in the XIXth century use of solid-state fermentation for the transport of fungal strains intercontinentally, mycobosci emerged out of a logistical need like other fermentation-based crafts. Looking to implement the novel mycoboscus craft as sustainable is a unique opportunity that needs an early defining of the technique as frugal and vernacular to become an effective icon of fair and post-extractive dwelling. To understand what the craft of mycoboscus comprises and establish a technical baseline, the thesis work first consists in the presentation of a biochemical and mechanical description of the system. This was done with a particular focus on the review and analysis of wood-decay fungi enzymatic activities. Life-cycle and risks assessment studies were then screened to elaborate recommendations about the conditions for the sustainable cultivation and use of mycobosci. Given the ubiquitous capacity of chlamydospore synthesis in the fungal species that are considered, and the sensibility of the mycoboscus life-cycle assessment to the organic nature of the substrates, a scenario of local production for local distribution is recommended to limit environmental risks and increase the sustainability of the cultivation activity by resorting to by-products. This model constrains and weakens the technical system of mycoboscus by making it dependent on supplies of varying quality, thus leading to consider design strategies to address this systematically. Three principal design strategies have been identified from this work. The supplementation strategy aims at chemically selecting or modifying the substrate to affect the enzyme activities, or the phenotypic expression of mycelia, for instance. Composition strategies consist of aggregates selection in the form of particles or fibres, for a diversity of shapes and strengths. Composition can also be achieved by designing composites with more than two phases to modify their behaviour under mechanical stress. The densification strategy can be executed by dense packing, cold or hot pressing. The principles laid out for enacting supplementation show potential for adapting cultivation recipes to local opportunistic sources. While the densification strategy adds to the embedded energy of mycobosci and was not studied further for that reason, composition strategies were developed to increase the specific strength and stiffness of the composites efficiently. Novel layouts were tested experimentally in compression and flexion with arming, jacketing and failure initiators. The experimental results display a net performance increase with some designs, which corroborates the hypothesis that composition can be a sustainable and efficient design strategy, and useful for mechanical failure risk mitigation. The effect of particle sizes on compressive and tensile load response has also been studied, and a novel use for the specific matrix modulus metric is proposed for evaluating rapidly the size effect on fermentation respiration and binding quality.
It has only been, and yet already, about fifteen years since the first industrial development for mycobosci started. Whilst proven mechanically competitive to EPS and XPS materials and more sustainable, the patent-protected industrialisation of mycobosci has not contributed to significantly reduce the use of these polluting solutions yet. The effect of the industrialisation process on the actual sustainability of mycobosci was studied through an integrative review. This use diffusion strategy is demonstrated to enhance the previously identified environmental risks that the technique presents, and shields knowledge from the public and academics. Industrialisation is shown to perpetuate the use of colonising and objectivising instruments that are detrimental to enacting sustainability, and hinder communities’ capacity for auto-determination. This indicates a need for the conceptualisation of an alternative use diffusion strategy. Knowledge production and maintenance is identified as a central interest for supporting these two entangled objectives of ecological and social sustainability. Based on the review of the mode of existence of vernacular architectures and terroir as eco-social designs, an alternative diffusion
strategy is devised, and the concept of design terroir is formulated. This mode of existence is shown to favour situatedness and social individuation through a craft-based epistemology. It also exhibits a capacity for the democratic scrutiny of, and intervention upon existing technological infrastructures should they turn unsustainable, with the development and retention of communities’ collective knowledge. Epistemological hypotheses were formulated on the basis of this review work, and tested in the context of architectural education. This study resulted in an enhanced tacit knowledge appropriation in students through craft activities. This presents enticing opportunities for the potential contribution to eco-social development of designs that follow principles of design terroir formulated in this thesis.
With contributions in scientific description of mycobosci, technical development of sustainable material design strategies, and in relational design theory, this thesis aims to support the emergence of a critical design research and practice of technology to foster the development of eco-social sustainability.