Buildings are being constructed. But new advances in biofabrication show that buildings can grow too.
Researchers in the UK have recently completed a prototype structure made by growing fungal mycelium inside a fabric-based form. The structure is a tent-like dome over six feet wide and shows that mushrooms can be used to push architectural design in new directions.
The system, called BioKnit, was constructed using a paste of mycelium and sawdust pumped inside a fabric formwork. Wool and linen were knit into a scaffold that was used to guide the growth of mycelium, which is the root-like branching structure of fungi that typically grows underground. Left to grow to a specific density and then dried, the mycelium filled the knitted scaffolding and hardened into a moderately strong experimental pavilion that looks like a cross between a gazebo and a piece of moldy bread.
The project was led by the Living Textile Research Group of Newcastle University’s Hub for Biotechnology in the Built Environment. Research group member Dr Jane Scott and PhD student Romy Kaiser explain in an email that the textiles have excellent biocompatibility with microbial systems and the structure has a much lower carbon footprint than one made with conventional building materials.
Mycelium is increasingly seen by researchers as a promising biomaterial for construction. Previous research has shown that mycelium can be grown into brick-like shapes and used to build structures, though most are experiments or works of art. Other plant-based materials, such as hemp, have been used to create building materials and similar components like insulation boards. These biomaterials are less resistant than conventional bricks, but have lower environmental impacts. Instead of being baked in kilns, biomaterials like hemp and mycelium bricks are hardened or dried naturally.
The researchers say there are drawbacks to building with bio-bricks, including the need for additional carpentry materials and potential weak points where mycelium and other materials meet. In the BioKnit prototype, the structure expanded into a fabric form to create a continuous material with no joints. Using textile formwork to hold this material together makes it even stronger than mycelium-based bricks alone, the researchers found.
“The main advantage of knitting technology over other textile processes is the ability to knit 3D structures and shapes without seams or waste,” Scott and Kaiser explain. “Growing as construction allows us to rethink much of the conventional building process: produce locally on site, reduce transportation associated with shipping individual parts for assembly, and develop sustainable practices.
They see BioKnit as a testing ground for the use of mycelium in non-load-bearing structures and also as a flexible insulation or interior material. Another goal of this work is to show that fabric-based forms can be used to create new types of architecture. “The ability to produce new geometries, curved surfaces and organic forms is very compelling for future interiors,” write Scott and Kaiser.
Their team is already exploring what that might look like. They recently completed another project using this same approach which emphasizes curved surfaces and organic shapes. Named the living room, the structure is a small cave-like pavilion of knitted wool on which mycelium has grown and hardened. The structure measures over 13 feet in diameter and is freestanding. As a bonus, the whole thing looks a bit like an upside-down chanterelle, deepening the connection to the natural roots of this new building material.