Namibia, facing a serious housing deficit, is exploring a groundbreaking and eco-friendly approach: mycelium-based construction. With a population of about 2.7 million, the country requires at least half a million new homes, but almost 90% of households earn less than N$2,700 ($144.69) per month, making traditional homeownership unfeasible for many. In response, the MycoHab project is leading the way in using mycelium, the root structure of fungi, to develop affordable and environmentally friendly housing.
How mycelium builds houses
Mycelium consists of a network of fungal, root-like threads that extend underground, drawing in nutrients and water. This adaptable material has recently garnered attention for its potential in sustainable construction. Mycelium can be grown on organic waste material, forming a dense, fibrous network that binds the waste into solid structures. These structures, once treated with heat to stop further growth, become strong, lightweight, and biodegradable building materials.
The process begins with combining fungal spores with agricultural waste byproducts, such as corn husks. This mixture is placed into molds and allowed to grow under controlled conditions. As the mycelium consumes the waste, it forms a solid mass that conforms to the mold. The resulting material, after heat treatment, offers a sustainable alternative to conventional building materials like concrete and wood.
The MycoHab project
The MycoHab project, working with the Massachusetts Institute of Technology (MIT), the architecture firm Redhouse Studio, and the Shack Dwellers Federation of Namibia (SDFN), is at the forefront of this innovative approach. MycoHab uses Namibia’s encroacher bush, an invasive plant species that covers 45 million hectares of land and negatively impacts the environment. Instead of burning the bushes, which would release carbon dioxide, MycoHab grinds them up to use as a substrate for growing oyster mushrooms. The mushrooms are then sold, and the leftover waste is compressed and baked into mycoblocks, with each block containing about 10kg of bush material.
In February 2024, MycoHab unveiled its first mycelium-based home to the public. Although still in the experimental phase, the project shows significant promise in providing a sustainable solution to the housing crisis, as stated by Magreth Mengo, the head of brand and marketing at Namibia’s Standard Bank. Homes constructed with mycoblocks are cost-effective, require less labor, and have a lower environmental impact compared to traditional construction methods.
Kristine Haukongo, the senior cultivator at MycoHab, addresses common misconceptions about these homes: “People think the house would smell because the blocks are made of all-natural products, but it doesn’t smell. Sometimes, there is a small touch of wood, but otherwise it’s completely odourless.”
Social and economic benefits
The MycoHab project offers several social and economic benefits. Firstly, it provides an affordable housing solution in Namibia, where many struggle to afford traditional homes. By using waste materials to create building blocks, the project reduces construction costs, making homeownership more accessible. Additionally, the project creates job opportunities in mushroom cultivation and mycoblock production, boosting the local economy. Environmentally, MycoHab helps mitigate the adverse effects of the encroacher bush. Repurposing the bushes instead of burning them reduces carbon emissions and supports the regeneration of Namibia’s grasslands. This approach also conserves groundwater resources, which are vital in a country with limited rainfall.
Environmental benefits
The project’s sustainability focus extends beyond housing. The mycelium-based construction process generates minimal waste and uses renewable resources, aligning with global efforts to minimize the environmental impact of the building industry. Traditional building materials, such as concrete and steel, have significant environmental drawbacks. Concrete production, for instance, is responsible for 4 to 8% of global CO2 emissions. Additionally, extracting raw materials for concrete, like limestone and clay, causes habitat destruction and pollution. Steel production is energy-intensive and also contributes to high carbon emissions.
In contrast, mycelium-based materials are renewable, biodegradable, and require less energy to produce. MycoHab estimates that mycoblocks store 0.8kg of CO2 equivalent per 1kg of material, compared to the nearly 1kg of CO2 emitted per 1kg of concrete. Mycelium’s insulating properties reduce the need for energy-intensive heating and cooling systems, further lowering the environmental impact of mycelium-based buildings. Additionally, mycelium blocks are fire-resistant, lightweight, and can be molded into various shapes and sizes, offering flexibility in construction design. Although they are heavier than standard bricks, they can be made faster, resulting in lower overall construction costs.
The future of sustainable construction
The MycoHab project represents a significant step forward in sustainable construction practices. By harnessing the power of mycelium, repurposing invasive plant species, and reducing carbon emissions, MycoHab addresses both the housing crisis and environmental challenges in Namibia. The project’s success could inspire similar initiatives worldwide, demonstrating that innovative, eco-friendly solutions can meet the growing demand for housing while protecting our planet.