It was the smell of wet earth, the quiet hum of mycelial fibres growing in the dark, that first caught my attention. Imagine panels that feel alive—thin as wallpaper, soft as fabric—and yet when flames lap at them, they don’t scream in toxic smoke.
Instead, they char, they protect, they stand. That’s what a team at RMIT University in Melbourne, Australia, set out to do: grow fungus-based sheets that might be the next generation of fireproofing for our homes.
Researchers at RMIT have developed a method to grow pure mycelium sheets—the underground network of fungi—using renewable organic waste. This process avoids grinding or damaging the fragile filaments, allowing the sheets to retain a natural, uniform structure.
By carefully controlling temperature, humidity, and nutrients such as molasses, and applying treatments like deacetylation, they have created material that is thin—almost like wallpaper—yet remarkably fire-resistant.
When exposed to flames or intense heat, the sheets naturally form a protective char layer that slows fire spread and shields the surface beneath. The longer this char remains intact under high temperatures, the greater its effectiveness as a fire barrier.
Another key advantage is its clean combustion profile—when these fungal sheets burn or reach the end of their life cycle, they release only water and carbon dioxide, avoiding the toxic chemicals typically produced by plastic-based fireproofing materials.
Four Key Challenges (Especially The Fourth)
While the promise is vivid, several hurdles remain. Among the many points raised in the research, four stand out—especially the fourth, which may decide how soon and how widely this idea can be adopted.
1. Speed And Scale Of Production
Fungi don’t grow as fast as plastics are manufactured. To produce large sheets or many panels will require either scaling up farms or harnessing waste from mushroom farms. Researchers have already begun discussions with mushroom growers to use their fungal-incorporated waste.
2. Fire Safety Rating And Performance Under Real Conditions
Laboratory tests are promising: increased ignition temperature; reduced flame height; formation of char; less toxic smoke. But these tests typically occur in controlled settings. Real building environments vary wildly (humidity, wind, actual flame sources, mechanical stress, UV exposure, etc.). The material needs to perform under fire codes, varying environmental conditions, and with durability over time.
3. Material Reinforcement And Composite Design
The pure mycelium sheets are delicate. To make them usable as cladding or other structural elements, reinforcement is needed. The team is exploring combining them with engineering fibres, layering them, making mats that delay ignition and reduce flame intensity.
4. Cost, Regulatory Approval, And Adoption In Construction Industry
This is the linchpin, and the most complex. It includes several sub-factors:
- Regulatory standards for fire safety are strict, well-established, and vary by country. Any new material needs to pass rigorous testing and certification before being used in walls, roofs, cladding.
- Cost competitiveness: plastics and conventional fire retardants/insulation have well-established supply chains, economies of scale; they’re cheap. Fungal sheets must become cost-competitive, or else adoption will be niche.
- Awareness and trust: builders, architects, regulators, homeowners need assurance that this material is safe, durable, consistent. Real-world demonstrations, long‐term case studies are needed.
- Lifecycle and supply chain issues: Where do inputs (waste, nutrients, growth facilities) come from? What are the environmental impacts over time (moisture, pests, biodegradation)? How easy is disposal or recycling? These are essential for regulatory bodies and sustainability certifications.
Small Stories, Big Implications
During the research process, Associate Professor Tien Huynh’s team managed to cultivate mycelium sheets so thin and uniform that they seemed almost weightless. When subjected to high heat, the material glowed faintly at the edges but maintained its structure, proving its resilience.
Their breakthrough involved developing a method to grow pure mycelium without mixing it with leftover feed material, resulting in sheets with a texture similar to leather.
In comparative fire tests, samples of the fungal sheet were placed alongside conventional plastic cladding. The plastic ignited rapidly, releasing thick black smoke, while the fungal material only charred and curled slightly yet continued to act as a barrier.
Researchers highlighted that in many fire incidents, the most significant danger comes not from the flames but from the toxic fumes and heavy metals released by burning synthetic construction materials. The fungal sheets demonstrated an ability to limit this risk by producing far cleaner byproducts when exposed to fire.
Optimism Balanced With Realism
There’s something deeply hopeful in this: a low-tech, bio-rooted material that could replace fossil chemical fire retardants, plastic claddings, toxic foams. A material that can come from waste, that composts at end of life; that doesn’t further pollute when disaster strikes.
In a world facing increasing fire risks—from climate change, more frequent wildfires, hotter summers, riskier supply of conventional materials—it offers a kind of gentle revolution. The fungal sheets likely won’t, in the next few years, replace all fireproof materials.
But they might find places—in decorative cladding, in insulation under protected surfaces, in retrofit situations—where their advantages (sustainability, low toxicity, renewability) outweigh cost or regulatory lag.
What Could This Mean Beyond Australia
If this research is successful and scaled, it could matter globally. Countries with large mushroom industries (India, China, parts of Africa, parts of Asia) already have waste streams that could feed such bio-materials. Tropical climates where fungi grow fast might offer speed.
Regulatory pressures (especially following tragic fires) could push governments to prefer safer, greener materials. And consumers increasingly demand not just safety, but environmental responsibility in homes and buildings.
Conclusion: The Charred Path Ahead
Fungus may not look glamorous in its raw form. But these fungal sheets are quietly brave. When flames come, they don’t panic; they transform into protection. That charred mask becomes shield.
The path ahead—scaling, cost, certification—is steep. But every breakthrough, every test passed, every spark that doesn’t spread, brings us closer to homes that protect not only us—but the planet too.
