Use of Biomaterials in Construction is growing rapidly as builders seek to reduce construction emissions and energy use. In addition, they are looking for more sustainable materials that are not harmful to people and the environment.
One of the most popular biomaterials is chitin, a fibrous substance found in crustaceans and insects, as well as the cell walls of fungi. The material is able to be used for insulation, soundproofing and other purposes.
Biodegradable
The use of biodegradable materials can help reduce construction waste and the need for natural resources. It can also improve indoor air quality and decrease carbon emissions. However, many of these materials are expensive and must be used in combination with other sustainable design techniques. This article discusses some ways to incorporate these materials into architecture.
Unlike synthetic plastic, biodegradable materials break down without producing toxins and can be reused for multiple life-cycles. They are made from renewable materials, such as vegetable oils and fats, corn starch, soybeans, sawdust, wood chips, recycled food waste, and plastic waste. They can also be combined with other materials to create composites. They are also more environmentally friendly than synthetics, as they release less CO2 into the atmosphere and require fewer energy to produce.
While some biodegradable products have been around for centuries, other new technologies are making them more widely available. For example, fungus-based biomaterials can replace traditional synthetic acoustic insulation. This allows architects to make buildings more energy-efficient and provides insulation while reducing construction waste.
Another type of biomaterial is hemp lime, a concrete alternative that uses the fibers of the plant to form a lightweight material that combines with clay to create bricks and blocks. Hemp lime is non-toxic and breathable, which can help reduce mold growth and improve indoor air quality. The material is also durable and has a high insulating value. Moreover, the use of hemp lime can eliminate the need for cement, which is a significant source of carbon dioxide emissions.
Carbon sequestration
The construction industry is responsible for 40% of global carbon emissions, so it needs to make dramatic changes to its sustainability. Biomaterials can help by sequestering carbon during growth, regenerating soils in between cultivation, and being a net carbon sink at the end of life. These materials can also reduce the embodied carbon of a building, reducing its environmental impact by converting greenhouse gases into useful products.
Fungi and other biological materials can be used to produce a wide range of products, including bricks, concrete, insulation, and even furniture. They are not only an alternative to traditional materials, but also have the potential to replace plastic waste and contribute to a circular economy. The use of biomaterials can have a huge impact on the sustainability of the built environment, and can help achieve the Glasgow Climate Pact’s targets.
Using biological materials in buildings isn’t new – wood and bamboo have been used for centuries, and compressed straw and lambswool are common building components. However, increasing knowledge of microbiology and synthetic biology techniques is allowing new biomaterials to enter the market. These include self-healing concrete, mycelium insulation, and chipboard made from food waste.
The research on these materials is exciting, and a lot of work goes into understanding their properties. Nonetheless, it remains a challenge to integrate them into architectural design. The best approach will be productive lateral thinking, and finding ways to unlock the full potential of these materials. Darshil Shah will be presenting more information on the use of biomaterials in sustainable design at the online RIBA Smart Practice Conference 2021: Stepping up to the Climate Challenge on 30 September.
Environmentally friendly
While the construction industry is known for its waste and environmental impact, many new developments in building materials have the potential to change this. In particular, innovative biomaterials can reduce the need for non-recyclable processed elements and provide a framework for achieving net zero buildings. These materials are able to absorb carbon, sequester water and improve air quality. In addition, they are often produced locally, reducing the need for transporting raw materials.
Biomaterials are not limited to natural substances, and can also include synthetic ones such as asphalt. They are typically not harmful to humans and can be repurposed after they’ve served their purpose. They can also be made with recycled materials such as glass, paper and plastics.
Another emerging area of research is fungal biomaterials, which can offer novel functionality that can inspire and influence the design process. For example, mycelium can be used to produce building materials with self-healing and regenerative properties.
These innovations can help the industry reduce embodied energy, a measure of the energy that is required to make a material. In addition, they can also reduce landfill and other waste by reusing materials from the site of construction or integrating them into a building’s overall energy design. In a recent RMI interview, Wil Srubar III, an associate professor at the University of Colorado Boulder, discussed his work with these sustainable materials. His projects range from living concrete to algae-based portland cement and a marketplace for embodied carbon offsets.
Economical
The use of biomaterials can dramatically reduce the environmental footprint of construction by lowering natural resource consumption, carbon emissions, and landfill waste. However, to be economically viable, these materials must compete with petrochemical technologies on price and performance. This is why it’s important to focus on sustainability from the start. The bio-based economy will need to ensure that biomaterials are sourced sustainably and repurposed. It should also avoid deforestation and harmful land-use change, and should promote biodiversity.
The success of cross-laminated timber (CLT) over the past decade provides a blueprint for other biomaterial innovations. Its ability to overcome political, regulatory and technical challenges has enabled its widespread adoption. This technology is reducing the need for conventional concrete, which has a high embodied energy, and improving air quality and thermal performance in buildings.
Another promising approach is using mycelium to replace synthetic acoustic insulation. Mycelium can be grown from a variety of organic wastes and can repurpose existing building materials. In addition, it can break down pesticides and petroleum products that contaminate local ecosystems. Mycelial composites can be heat treated to make them inert, but they can also be heated to release their cellular components and offer new active properties such as self-healing or partial self-organization.
Some startups, such as Biohm, are working to develop truly sustainable building materials by reusing organic waste from fruit peels, grass clippings, and more. These bio-based additives can replace plastic in construction, reducing the amount of garbage that ends up in landfills.