Fully Compostable ‘Mushroom Shoes’ Unveiled in London — What it Means and What the Science Says

In late June this year, a proof-of-concept trainer that literally grows its sole from fungi was shown to the public in London. The shoe — a project called the Korvaa concept — pairs mycelium (the thread-like root system of mushrooms) with other biologically grown materials so that almost every component is compostable or bio-based. The team behind it says the point was not to start a fast-fashion craze but to demonstrate a different way to make complex consumer goods: fewer, deliberately chosen materials that are designed to be returned to soil at the end of their life. According to The European, the Korvaa shoe was unveiled at the Future Fabrics Expo in London and uses a mycelium sole grown in seven days alongside a bacterial-nanocellulose upper and a 3D-printed PHA scaffold.

How Mushroom-Based Materials Compare to Conventional Leather and Plastics

Claims that mushrooms will replace leather or plastic make for good headlines — but the environmental reality depends heavily on how the material is made, finished and powered. A peer-reviewed life-cycle assessment (LCA) of Reishi, MycoWorks’ “fine mycelium” leather, found a cradle-to-gate carbon footprint as low as 2.76 kg CO₂-equivalent per square metre — roughly 8% of the bovine leather benchmark modelled in the same study — and highlighted energy use and sterilisation as the main improvement opportunities. The study suggests that Reishi’s manufacturing process and low plastic content are the reasons for its much lower carbon figure.

But not all mycelium leathers are identical. A separate, detailed LCA of a different mycelium product (Mylea) produced in Indonesia reported very different results: the finishing process and electricity use pushed the footprint to about 57.15 kg CO₂-eq per m², with electricity alone contributing roughly 46.53 kg CO₂-eq. The study concluded that the single biggest lever for improving environmental performance was switching the energy source used in production, highlighting that local production conditions and finishing choices are decisive.

Those two published studies highlight a key point: “mushroom leather” is not a single, inherently low-impact material. Its sustainability depends on the feedstock (what the fungi are grown on), the manufacturing method (passive mycelium growth vs. energy-intensive processing), and the finishing chemistry (coatings, adhesives, dyes). If a factory relies on coal-based electricity and energy-heavy finishing, the climate benefits can disappear; but if it uses low-carbon power and minimises polymer content, the footprint can be far lower than that of animal leather. Process design and energy sourcing remain the biggest hotspots to address.

Prototypes, People — Case Studies from London and Beyond

The Korvaa concept shown in London brings together Ecovative (mycelium soles), Modern Synthesis (bacterial nanocellulose uppers) and Ourobio (PHA scaffolding) to make a shoe out of just five biodegradable components. The designers are clear it’s a demonstration: it proves the technical possibility of replacing dozens of petrochemical parts with a handful of biologically derived materials — and it shows where the remaining engineering gaps (water resistance, grip, manufacturability) sit. Jen Keane of Modern Synthesis described the project as one that “unlocks unparalleled creative freedom” by combining materials the way nature does.

Vivobarefoot, a London-born brand that has been experimenting with compostable and mycelium-based materials for years, has followed a parallel route: it recently launched a Gobi sneaker that uses a mycelium-derived material called HyphaLite and is pairing innovation with long-life programmes to avoid premature disposal. Vivobarefoot also runs ReVivo — a refurbishment and resale platform that has reconditioned tens of thousands of shoes — as a reminder that material innovation is only part of the solution if products are still discarded quickly. Charlotte Pumford, the brand’s director of sustainability, said finding a plant-based material that performs at the level customers expect has been a long pursuit. According to FashionNetwork, 2025, the Gobi is the brand’s practical step toward eliminating plastics from its vegan lines.

These are real, practical stories: Korvaa is a staged prototype shown at an industry event; Vivobarefoot is launching customer-facing products and circular programmes; and designers such as Stella McCartney and Adidas have trialled mycelium uppers in limited runs for years. At the consumer end, The Guardian reported in 2024 on Vivobarefoot’s compostable, 3D-printed trials, quoting company founders who explained that the goal is “scan-to-print-to-soil.” They also noted, however, that the first models still require industrial composting and involve trade-offs between durability and biodegradability. The article further quoted scientists reminding readers that shoes are complex products, and that lifecycle thinking — not single claims — should guide decisions.

As a short real-world case: Vivobarefoot’s ReVivo programme has restored tens of thousands of shoes, keeping footwear on feet and out of landfill while the company scales new materials. According to Vivobarefoot’s reporting, ReVivo refurbished over 62,000 pairs in one recent year — a reminder that extending product life remains one of the most effective climate-positive moves a brand or consumer can make.

What all this Means for Consumers, Brands and Policy — Clear Actions

If you’re a consumer wondering whether to buy a mushroom-based shoe, two practical rules will help: first, prefer durability and reparability over novelty; second, treat compostable or “biobased” labels as starting points for questions about where the product should be sent at the end of life (home compost, industrial compost, or take-back). As the Guardian reported, many early compostable shoes still require industrial composting and contain materials that complicate home disposal.

If you’re a brand or designer, the takeaway is clear: test the whole lifecycle, not just the feedstock. The peer-reviewed Reishi LCA shows that when mycelium production avoids heavy sterilisation and minimises polymer coatings, the carbon footprint can be very low. However, it also flagged energy use and finishing as key hotspots for improvement. By contrast, the Indonesian LCA found that production choices and the local electricity mix can push the footprint much higher, underscoring that energy sourcing is often decisive.

Policymakers and industry bodies should focus on three levers that would accelerate genuine benefits: clearer labelling and standards for biodegradability, incentives (or requirements) to use low-carbon electricity in biofactories, and support for repair/resale systems so materials stay in use longer. The One4Leather/industry commentary and the LCA literature warn against simplistic “vegan = better” messaging without standardised, transparent LCAs.

Here are six practical, evidence-based steps anyone involved in footwear — maker, buyer or regulator — can take right now:

Ask for an LCA or disclosure that covers cradle-to-grave impacts, not just raw material claims. Reputable LCAs exist for some mycelium materials, and they reveal where savings come from.
Treat repair and reuse as priority actions. Extend product life through take-back, refurbishment and resale programmes (Vivobarefoot’s ReVivo is a model with scale).
Push for low-carbon energy on factory sites. Many LCAs show electricity as the main hotspot — switching to renewables cuts impacts quickly.
Demand clear end-of-life instructions and infrastructure. If a shoe is industrially compostable, that must be written front and centre — and brands should facilitate take-back where municipal composting is not available.
Favour minimal polymer coatings and transparent finishing chemistry. The lower the polymer fraction, the higher the chance of true biodegradability.
Support standards and third-party verification. Independent testing and certification for biodegradability and LCAs reduce greenwashing and help customers make informed trade-offs.

Conclusion

Mushroom-based materials are not a silver bullet, but the recent London prototypes and commercial launches show the category’s technical viability and the industry’s appetite to try radically different material systems. The research literature is clear: with the right process choices and clean energy, mycelium leathers can be very low carbon; with the wrong choices, they can be no better — or worse — than existing alternatives. The sensible path is to combine material innovation with policies and business models that keep shoes in use longer and ensure that, when they do return to the earth, they actually nourish it.