Sustainable Architecture | Compostable Building Materials

When people think of mushrooms, they primarily think of food and then of their importance to the forest ecosystem . However, there is now great interest in their potential as a renewable raw material for environmentally friendly composite materials. The spectrum of possible applications ranges from food packaging to furniture to building materials .

Sustainable building materials made from mushrooms could shape the construction of the future, as they are lightweight, durable, water-repellent, and compostable. Combined with proven renewable raw materials such as wood, clay, or straw , mushrooms offer a basis for a wide variety of composite materials—also due to their excellent ecological footprint.

But not all fungi are suitable. Six million species are currently known, of which only 120,000 have been studied. Projects for new building materials are exclusively working with white-rot fungi. Black mold, on the other hand, is harmful to health and is not considered suitable as materials. White-rot fungi include all edible mushrooms.

To produce mushroom-based building materials, the above-ground fruiting body, which constitutes only the smallest part of the organism, is not used. Instead, international research focuses on the mycelium, the underground network of cell filaments (hyphae). Depending on the species of mushroom, this network can reach a size of over one square kilometer in nature.

Growing building blocks

The production of composite materials, such as cuboids used like building blocks, is quite simple and could even be implemented in disused industrial halls or mine tunnels. For the manufacturing process, agricultural residues such as grain chaff or wood chips are mixed with water and the mycelium. The residues form the substrate, i.e. the food for the fungi. During the metabolic process, a fine network of mycelium permeates them. In this way, a purely organic composite material is created during the growth phase of around two to three weeks in the incubator. This composite material can be shaped into a variety of desired forms and is stabilized through thermal treatment. The final result can be, for example, a leather-like material or a composite material.

This allows for the cultivation of mushroom materials with very different properties. Durable, stretchable, tear-resistant, dense, elastic, open-pored, or even soft and fluffy—the possibilities are virtually endless. The final result depends on the combination of mushroom species and substrate. Parameters such as temperature, humidity, and the duration of mushroom growth also determine the properties of the final product. Heating the mushroom mycelium ultimately stops growth.

The result is that it's possible to produce anything from wafer-thin, flexible layers to solid, thick blocks, making the material suitable for a variety of applications. These composite materials are suitable for both new construction and renovation: They offer thermal insulation, sound insulation, moisture regulation, and fire resistance. Furthermore, at the end of their useful life, they can be used as a substrate for a new structure or simply composted.

Research for serial production

In Germany alone, several universities and institutes are now researching mycelium building materials and are making progress toward serial production. Vera Meyer of the Technical University of Berlin and Dirk Hebel of the Karlsruhe Institute of Technology (KIT) are conducting fundamental research on this topic. They are considered leading experts in building with fungal mycelium.

Back in 2017, the KIT team led by Dirk Nebel, together with the Block Research Group of ETH Zurich, presented a load-bearing structure made of fungal material at the Biennale of Architecture and Urbanism in Seoul. The "Myco Tree" demonstrated how well biodegradable materials and lightweight construction technology complement each other. KIT is currently working on the production of wood-based panels, such as OSB boards. Conventional panels contain up to 15 percent adhesive and must therefore be treated as hazardous waste. Alternatives to chemical adhesives are now being sought.

Vera Meyer and a 40-person team at the Department of Applied and Molecular Microbiology at TU Berlin are focusing primarily on basidiomycetes—which account for around 30 percent of all fungal species—to transition some areas of the energy-intensive construction industry, such as insulation materials , into a biotechnological circular economy. Mushroom mycelium, replacing petroleum-based materials, is intended to become a basic resource for composite materials in buildings and furniture. The first house made entirely of mushrooms is planned for 2030.

A research team from the Fraunhofer Institute for Environmental, Safety, and Energy Technology (Umsicht) is testing how fungal-based materials can be manufactured, shaped, and functionalized in its "Mycelium Technology Center," as well as testing their behavior. The facility also provides companies with an introduction to the topic and advises them on the potential of mycelium materials. At the international construction trade fair BAU in Munich in January 2025, Umsicht presented, among other things, a prototype of a facade element. The element combines integrated photovoltaics for power generation, weather protection, and thermal insulation made from fungal material. It was developed in a joint project with the Fraunhofer Institute for Solar Energy Systems (ISE).

Good insulating properties

Researchers at the Fraunhofer Institute for Applied Polymer Research (IAP) in Potsdam are also intensively investigating mycelium-based materials from agricultural residues. Hannes Hinneburg and his team are converting locally available plant waste products into sustainable materials, focusing on edible mushrooms and tree fungi such as the oyster mushroom and the tinder fungus. In particular, the team is currently working on developing mushroom-based insulation panels for interior construction, as the material has similarly good insulation values ​​to expanded polystyrene (EPS) foam. Their use as sound absorbers for walls and ceilings is also being tested. Such sound insulation would not only be sustainable but also material- and space-saving if implemented in thin layers.

Although structural components made from fungal material are not yet feasible, there are a few companies already developing and marketing other mycelium composite materials for the construction industry. Wall panels, insulation boards, and adhesives for mineral materials or floor panels made from these organic composites are currently available. In Switzerland, for example, the company Mycho Suisse is one of the pioneers. It has been researching the potential of fungi for over ten years, combining cellulose fibers with mycelium to replace petrochemical products with sustainable alternatives.

The first house made entirely of mushrooms is planned for 2030.

In the USA, the company Ecovative Design combines the mycelium with grain husks and plant stems, among other materials. The material can be used for packaging and decorative items such as candle holders, but also as a building material. The manufacturer offers its "Mushroom Insulation" as an insulating material, acoustic tile, and sandwich panel. For the latter, the fungal network is placed between two layers of wood, with which it naturally bonds through its growth process.

It's only a matter of time before the first products are mass-produced in this country. Research laboratories are working on expanding its potential applications in the construction sector to include load-bearing components. Thus, the mushroom material is likely to lose its exotic status in construction in the near future, just as clay, straw, and seaweed insulation have already lost.

Raw material also for textiles

In the future, we will probably not only come across houses whose sound insulation and interior walls were made with mushroom mycelium and whose decorations are partly made from the renewable raw material.

For example, Dutch designer Aniela Hoitink and her company Neffa create sustainable fashion from mushrooms. She aims to contribute to reducing textile waste. According to the designer, the mushroom fabric, called "Myco TEX," is the only 3D-produced, seamless, tailor-made textile made from mushroom mycelium. Once these textiles have reached the end of their useful life, they can be easily composted.

Anyone interested in experimenting with mushrooms can do so through Grown Bio. The Germany-based manufacturer of mushroom-based packaging offers a "Grow It Yourself Kit" that lets you experiment with the material and create your own products, such as pots, sculptures, and lamps.