A material which is based on a network of fungal strands has emerged as a potential solution to flammable cladding on buildings, new research has found.

(above image: The research team Nattanan (Becky) Chulikavit (left), Associate Professor Everson Kandare (middle) and Associate Professor Tien Huynh (right) in their lab at RMIT’s Bundoora campus.)

A research team at RMIT University in Melbourne have created a way to chemically manipulate the composition of mycelium in a way that harnesses the fire-retardant properties of the material.

Essentially speaking, mycelium is the root-like structure of a fungus and consists of a network of thin fungal strands.

The material has strong fire-resistant properties – something which gives it considerable potential to be used as a fire proofing material.

Under normal circumstances, fungi are found in a composite form that is mixed with residual feed material.

However, the research team has found a way to grow pure mycelium sheets that can be layered and engineered into a range of uses.

Instead of pulverising the mycelium’s filament network, the team instead used different growth conditions and chemicals to make the sheets into a thin and uniform material.

The researchers believe their breakthrough could eventually lead to improved and eco-friendly cladding for buildings.

They are now looking to create fungal mats reinforced by engineering fibres to delay ignition, reduce the flaming intensity and improve fire safety ranking

(Flammable cladding contributed to the rapid spread of fire in the Grenfell Tower inferno in which 72 people were killed in London in 2017)

Associate Professor Everson Kandare, an expert in the flammability and thermal properties of biomaterials, said the mycelium has strong potential as a fireproofing material.

He added that the material can be produced from renewable organic waste and is not harmful to the environment when burned.

This contrasts with composite cladding panels that usually contain plastic material that produce toxic fumes and heavy smoke during burning.

“The great thing about mycelium is that it forms a thermal protective char layer when exposed to fire or radiant heat. The longer and the higher temperature at which mycelium char survives, the better its use as a fireproof material,” Kandare said.

“Bromide, iodide, phosphorus and nitrogen-containing fire retardants are effective, but have adverse health and environmental effects. They pose health and environmental concerns, as carcinogens and neurotoxins that can escape and persist in the environment cause harm to plant and animal life,” said Kandare.

“Bioderived mycelium produces naturally occurring water and carbon dioxide.”

For fungi-based products to be converted into a commercial product, one challenge to overcome is that fungi are slow to grow and relatively difficult to produce at scale.

This compares with plastics which are quick and easy to produce.

However, the research team have received approaches about using waste products which have fungi incorporated into them from the mushroom industry.

This would avoid the need for new farms in order to produce the fungal material.

This project is a collaboration involving RMIT University, the University of New South Wales, the Hong Kong Polytechnic University and the Australian Research Council Training Centre in Fire Retardant Materials and Safety Technologies.