Mycelium Insulation: Everything to Know About Sustainable, Fungi-Based Panels

That pesky pink foam in your walls is responsible for keeping your home warm and the envelope protected. However, not all insulation types are created equal. Many contain hazardous materials that harm the planet or the building’s inhabitants. Experts in the building sector have been seeking solutions for insulation panels that are healthy for humans and the climate. Is mycelium insulation the answer?

What Is Mycelium Insulation?

Mycelium insulation is an insulation material made from fungus. Mycelium is an aspect of the fungus structure, resembling roots. The collective mycelium is constructed of countless hyphae, which are the reason fungi grow as effectively as they do. They are productive nutrient absorbers, and they even move water. To the naked eye, mycelium looks like a white, feathery mold. 

Using this material for insulation reveals a fascinating world of plant-based possibilities. Scientists combine the mycelium with a feedstock — this is most commonly biomass waste. The mycelium’s characteristics allow these materials to bind extremely well. Experts suggest the structure could even be similar to plastic-based insulation options.

Mycelium is a highly malleable material that forms insulation, bricks, foam and more. Carbon-friendly homes seeking more environmentally aware options should consider mushrooms.

Is Mycelium Insulation Sustainable?

Is using fungi for insulation as sustainable as it sounds? Yes. There are numerous reasons why fungus is a great, eco-friendly alternative. The most obvious is that it is a renewable resource. Other materials, like fiberglass and plastic, have waste mining and manufacturing practices that use tons of energy and water. They also produce copious waste and pollutants, resulting in a product that has low reusability. 

Mycelium insulation encourages a circular economy by being bio-based. Homeowners can recycle or compost old insulation, replacing it with newly grown materials that likely nourished the planet while they grew. Mushrooms and other fungi contribute greatly to healthy soils and nutrient density, making it optimal for related industries, like agriculture. 

Countless insulation materials release hazardous pollutants, like volatile organic compounds. These disrupt indoor and outdoor air quality while posing a risk to human health. There are no toxic byproducts of mycelium insulation that would harm the air or inhabitants of a building.

Research has shown even composite mycelium-based insulation still has a drastically lower carbon footprint than other materials. The most critical tell is a life cycle analysis (LCA). An LCA for mycelium insulation derived its eco-friendly properties:

• Optimal thickness only needed to be 0.08 m for these results.
• Led to 87.4% energy savings in winter and 55.9% in summer.
• Rose winter temperatures indoors by 1°C and lowered summer temperatures by 4°C.
• Reduced carbon emissions by 72%.

Is Mycelium Good for Insulation?

Mycelium insulation has been tested and commercialized for awhile. It is also lightweight like polyurethane spray foam and foam concrete. Most builders judge an insulation’s ability to protect an envelope based on its R-value, or its ability to manage thermal resistance based on the insulation’s materials, thickness, application and other properties. It is usually derived from this equation:

R-value = temperature difference x area x time ÷ heat loss

The higher the R-value, the better the insulation. You can increase the R-value by increasing the thickness of the insulation layer, but not everyone wants thick walls. However, not every geography needs intensely high R-values. If you live in a warmer climate, lower numbers will perform adequately.

What is the R-value of mycelium insulation based on other insulation types? It ranges from R-3 or R-4 per inch of thickness, whereas extruded polystyrene (XPS) is around R-5 per inch. Even though mycelium insulation is not the highest performer, it isn’t the lowest. 

Plus, it comes with a long string of benefits builders will find desirable.

What Are the Disadvantages and Advantages?

Fungus-based insulation panels sound like an interesting prospect, especially because the material is renewable. What are the pros and cons of this building option to ensure a balanced understanding of its strengths and weaknesses?

Pros

As previously explored, mycelium insulation could be the leader in sustainable insulation. It is a renewable resource that is biodegradable and compostable, meaning it promotes a circular economy. It is also carbon-negative and nontoxic. Research shows it could sequester 16 tons of carbon monthly.

Other facets that make mycelium ideal insulation are its flame-retardant qualities. Mycelium is naturally resistant to flames. It will not melt or ignite like other insulation materials are prone to do. 

Finally, mushrooms and other fungi grow exceptionally fast. They are cheap to produce, making it a cost-effective option for industries and homeowners alike. The material can grow in countless conditions, making it agreeable and versatile in numerous environments. Operations can meld with existing infrastructure, reducing upfront costs and long-term production expenses.

Cons

The most prominent deterrent to mycelium insulation is its load-bearing capacity. It is lightweight, making it easy to work with. Plus, it doesn’t place many burdens on the home. However, it is not capable of carrying as much weight as other thicker insulation or cladding.

Despite fungi’s integrability with manufacturing operations, this doesn’t necessarily imply it is plug-and-play. Production lines will need to find streamlined ways of pasteurizing and sterilizing the mycelium to make it long-lasting. This may require overhauling processes or installing new technologies. Some businesses may not want to bother with this aspect of it, thereby dismissing the potential for mycelium altogether. 

It is also not a market-competitive product as a still relatively new idea in the insulation world. Most consumers — B2B and B2C — default to the market’s mainstays. It may be awhile before mycelium becomes a top-contender for buyers, much less a household name. The industry will need to collaborate on ways to publicize its benefits and communicate its efficacy to make it gain popularity.

Mushroom-Based Insulation Panels

Nobody would think to look to foragers to find the next big insulation material, but mycelium could be the disruptive insight builders need. Creating a robust building envelope is more important than ever, as old materials are becoming subject to controversy and climate-friendly infrastructure is essential. Mycelium insulation could be the greener, cleaner alternative, saving industry professionals countless dollars and tons of carbon in the long term.