Mycelium-based composites (MBC) have gained attention in research and industry as environmentally favorable substitutes for materials in various applications, including packaging inserts, textiles, automotive and even electronics. As construction materials, MBCs show promising characteristics as fully bio-based thermoacoustic insulation. To investigate the potential environmental impacts of the production, use and end-of-life of MBC acoustic insulation panels and their mounting system, we conducted a cradle-to-grave life cycle assessment (LCA) based on real-world production planning data and supplementary literature data. Life cycle modules and system boundaries were chosen following EN 15804. A life cycle impact assessment was carried out based on select impact categories from the Environmental Footprint (EF 3.1) framework. Uncertainties and sensitivities were examined based on a Monte-Carlo simulation and contribution to variance. Energy use for incubation and drying during the manufacturing stage is the most important contributor in most impact categories, including global warming potential. This is further underlined by the large sensitivity of the results to uncertainties related to energy-use. Overall, the manufacturing stage is the dominant life-cycle stage in terms of potential environmental impacts. Generally, our results agree with literature values of LCA studies on similar materials, when normalized for mass and volume. Tracing biogenic carbon throughout the product system shows an early release of over 10 % of the stored biogenic carbon during the manufacturing stage as opposed to a release of all remaining stored carbon during disposal and energetic recycling.