Samorost researchers confirm its properties in tests for flammability, pressure, tensile strength and friability
A team of Samorost scientists has proved in laboratory tests that mycocomposite could be the future of construction. The results show that it can effectively replace traditional polystyrene, plus it excels in burn tests, which means it is safer in the event of a building fire. In addition, it is environmentally friendly, fully degradable and made from recyclable material. Its lightness, strength and other exceptional properties make it key to a sustainable future for the construction industry.
Mycocomposite: an ecological revolution in construction and design
We can think of it as combining two worlds – the mycelium and cellulose-containing waste such as sawdust, paper or pellets. The result? Mycocomposite. This material has the unique property of remaining alive when crushed and placed in a mould. In fact, the fibres of the mycelium rejoin and the mycelium clumps together, taking the shape of the mould it is in. Mycocomposite is a natural and sustainable material. It has the potential to replace its non-organic counterparts such as polystyrene.
The Samorost project, which explores the use of mycocomposite in construction, architecture and design, has produced fascinating results. “We already know that it is environmentally friendly and biodegradable, self-supporting, lightweight and strong, and hydrophobic on the surface. We have tested its health safety and have gone even further,” says Libor Vošický of building savings bank Burinka (meber of Erste group).
And how did the material perform in the tests?
- Flammability test: Mycocomposite burns more slowly than wood. It does not drip hot droplets into the surroundings, which improves safety in the event of a fire. Thus, in the event of a fire, mycocomposite provides a longer time to evacuate.
- Pressure test: Mycocomposite is more durable than polystyrene. Its compressive strength makes it a suitable material for various areas in the construction industry.
- Tensile strength test: Mycocomposite is as strong as cork. It can therefore be used in the construction of lightweight and durable structures.
- Friability: Mycocomposite has the same good friability (cohesiveness) as polystyrene, which means it can be used to create strong and stable structures.
Is it flammable?
Burning tests have shown that mycocomposite has significantly better fire performance than particleboard or OSB. “The burning behaviour of mycocomposite is most similar to wood. Wood burns easily and quickly, while mycocomposite gradually delaminates and loses strength more slowly. The current test confirmed the basic fire classification in category E. Our ambition is to get to category C with further tests, which will confirm that mycocomposite has much better fire properties than chipboard or OSB,” says Jakub Seifert of MYMO, which is behind the research part of the Samorost project.
Increased fire resistance is just one of the many important properties that distinguish mycocomposite from existing building materials. Its environmental properties, strength and mouldability make it a promising candidate for the future of construction and design.
Mycocomposite: A material that resists pressure
You can think of it as a test of strength – mycocomposite versus pressure. And the result is clear: mycocomposite is more durable than polystyrene. But to what extent?
The test is carried out by gradually increasing the pressure on a cube with a 10 cm edge until its deformation reaches 10%. For a cube made of mycocomposite to deform by 1 cm, the press would have to apply a force equivalent to 199 kg. That’s the weight of an African lion or three adult women.
Mycocomposite testing is specific. “The mycelium shrinks in volume as it dries. That’s why the cubes were put into moulds that were 6 mm larger and, when dry, were close to 10x10x10 cm. The individual sizes of the cubes were therefore slightly variable, and therefore the force exerted corresponds to a pressure of 180 kPa,” explains Jiří Vele from MYMO.
And what does this test tell us? This environmentally friendly material is more resistant to external pressure than both ordinary polystyrene and stabilised polystyrene foam, which is often used for floor insulation. Mycocomposite is rivalled in the pressure test only by extruded polystyrene, which is used to insulate flat roofs.
Mycocomposite is therefore offering itself as a replacement for polystyrene, which is a huge burden on the environment. It is further proof that it is not just an interesting experiment, but has the potential to change the way we think about protecting our planet in construction. It is a step towards a more sustainable future.
Tensile strength: It has the strength of cork
The bend-tested tensile strength, or flexural strength, tells us how a material will behave if it performs the function of a beam or girder. This is important for the construction of ceilings and floors.
We tested a 4x4x16 cm beam made of mycocomposite. We gradually applied pressure to it and found that it had properties comparable to the strength of cork. It is therefore stronger than ordinary polystyrene, but less strong than wooden materials. This means that mycocomposite is not suitable as a beam or girder carrying heavy loads. But its light weight makes it self-supporting.
Friability: as cohesive as polystyrene
The friability test tells you how cohesive the material is internally. How much force is needed to tear the material apart? We found that to break a 42x400x600 mm board, we need a pressure of 100 kPa. The result is comparable to 70F facade polystyrene.
Conclusions of the tests
The laboratory tests of the mycocomposite in the Samorost project were carried out during the summer of 2023. We tested flammability, tensile strength, pressure and friability. And the results give us the green light to definitely continue with the project.
Mycocomposite can replace almost any polystyrene in the construction industry: for wall, roof, floor and interior insulation, for eliminating thermal bridges and for sound insulation. It minimises thermal bridges. In addition, it performs better in burn tests, is more durable and provides greater protection when evacuating a burning building. Most importantly, it is made from waste and fully degradable. In addition, it is a beautiful material that creates original and non-repetitive structures. It can therefore also be used for interior design accessories.