Is mycelium bio-composite a suitable building material for irish construction?

Weronika Multaniak

Test Methods
Technical Investigation & Case Studies
Hot/ Cold Box & Physical Prototype

For copy of full dissertation, contact:

David Knight
Jim Roche

With the constantly increasing construction and demolition waste in Ireland, we should consider more sustainable building materials that can be easily recycled or returned to the ground at the end of their life cycle.

A sustainable and natural material that has been getting some recognition around the world in recent years is mushroom mycelium. Mycelium is a network of hyphae that weaves its way around a substrate to break it down for nutrients and eventual fungal growth. By cutting the process short and disallowing the fungi to grow, a mycelium product can be achieved with mycelium acting as a bonding agent for the substrate it grows on. This study explores the process it requires to develop the bio composite, as well as case studies that used the mycelium material in construction. The developed mycelium bio composites were then subjected to a number of tests to see if it is a suitable building material in Ireland. 

A site visit was conducted to a local mushroom growing facility where the process was explained in detail. Following that, the theory was applied to growing mycelium bio composites. Starting with the growth of mycelium on agar plates to inoculating the lignocellulosic substrates. The substrates were then transferred into the moulds to ensure a standard size. Once the bio composites were harvested, they were subjected to a number of tests to find their properties. The tests included: the hot/ cold box test to determine the thermal conductivity, the capillary water absorption test to show the water uptake coefficient, and the compressive strength test to calculate the compressive strength. 

The results of the said tests were compared with other building materials. Those proved that while the water uptake coefficient was extremely low in comparison, both compressive strength and the thermal conductivity were subpar. This proved that the material was unlikely to be used as a structural component or insulation. While it is possible that the mycelium bio composites could be suitable as cladding, external or internal, further testing should be considered deeming the overall result of this study as inconclusive. When considering further testing, the long-term effects of water exposure, fire testing, and soundproofing should be investigated.