Feb 24, 2020
Our built environment, including residential homes, creates a significant stress on the natural world through demand for raw materials. Finding ways to develop environmentally-friendly and bio-based building materials is an important, though underappreciated, aspect of sustainable building. One biotech startup is experimenting with using orange peels, mushrooms, and other natural materials to create carbon-neutral building materials.
A bio-economy focuses on producing products, such as food, feed, products, and bioenergy, using renewable biological resources. As homeowners, we tend to think of sustainability in terms of energy efficiency. The less energy we use in our homes, the less impact we are having on the planet. That certainly is true, though the materials that go into home construction also exercise an enormous influence on natural systems. The embodied energy footprint of a home is the total energy consumed during the production of a home. This extends from the mining, processing, and manufacture of materials to the transportation and final delivery.
In many cases, the increased energy efficiency of new home construction might take up to 80 years to offset the ecological impact of the structure itself. Embodied energy, then, is too often an ignored aspect of the total carbon footprint of a home.
One study finds that between 1900 and 2010, the volume of natural resources used in buildings and transport infrastructure increased 23-fold. Now, 800 billion tonnes of natural resource material is tied up in these constructions, globally. Of that, two-thirds are in industrialized nations. Looking to the future, the global building stock is expected to grow from approximately 163 to 184 billion square meters, from 2017 to 2026. Is it possible to build more homes and buildings while not causing increasing demand on our world's already-depleted natural resource stock?
For this to happen, the sustainable building industry needs to increase access to natural, carbon-neutral building materials that have a limited impact on natural ecosystems. There are some great building materials that can enhance and help to regenerate the natural world. Two such examples are wood certification programs that focus on sustainably-harvested lumber and wool insulation sourced from regeneratively-grazed herds. Products and programs like these can aid the sustainable building industry to quicken the transition towards a bio-economy.
A "biological house," then, is one wherein the majority of materials used for construction are sustainably sourced. These natural materials would be harvested, processed, and manufactured in environmentally-friendly ways. A biological house will not only have a lower carbon footprint through a focus on energy efficiency and thermal performance, but it will also drastically reduce the embodied energy footprint that comes with new construction.
Biohm is a UK-based startup founded in 2016 by Ehab Sayed. Among other activities, Biohm is in the process of developing and producing Orb (Organic Refuse Biocompound), a series of carbon-neutral building materials. According to Biohm's website, the natural world is the perfect place to look for inspiration in creating architecture where we can flourish. They comment that, over billions of years, biology has proven to be significantly more efficient than technology. That evolution is continually refining and optimizing solutions to overcome life's continuous challenges.
The company focuses on creating innovative and practical home building materials from waste sources of biological materials. For example, they collect over three tons of orange peels from the cafeteria of a local technology company office. These orange peels are subsequently used to create a cork-like orange peel board used for wall panels, floor tiles, and risers. They also collect dozens of tons of grass cuttings from the London airport each week as another raw, biological source for their bio-based home building materials.
The company is currently experimenting with using mycelium (the thin strands of filaments that are a part of fungi) as a natural insulation material. Mycelium can safely break down toxic compounds and waste products. Because of this, Biohm hopes that their mycelium-based insulation product can regenerate damaged ecosystems while also offering a healthy, carbon-neutral insulation alternative for homeowners. Mycelium insulation could potentially help reduce plastic waste while also providing higher insulation values than current synthetic options.
Another unique sustainability feature of Biohm is that it enforces the recycling of the products that it sells to homeowners. The circular economy focuses on designing out waste and pollution by keeping products and materials in use to regenerate natural systems. Relying on voluntary recycling, however, is not the most effective pathway for this transition to occur.
At Biohm, people who purchase their products are contractually bound to return any materials to the company at the end of their useful life cycle. The cost of collection is built into the upfront price, meaning that the company will theoretically have a reliable, "circular" source of raw materials from the products they produce.
Bio-based building materials are certainly not a new development. People have been using earthen building techniques for thousands of years, and sustainably-sourced lumber is a significant player in the building industry. Unfortunately, however, there are dozens of other building products that are almost exclusively sourced from synthetic, petro-chemical providers. Carpets, insulation, composite decking, and other elements of our homes continue to be dominated by synthetics.
Just because building materials are natural, however, doesn't make them any more environmentally friendly than their synthetic counterparts. Pine lumber that is sourced from clear cut forests, treated with dangerous wood preservatives, and shipped across the world is certainly not any more sustainable than the synthetic products mentioned above.
Truly sustainable bio-based building materials such as Orb focus on reutilizing waste sources of biological materials. Had the orange peels and grass clippings used by Biohm ended up in landfills, they would contribute to methane emissions that come from mixing organic and synthetic waste.
Certain bio-based building materials can also play a regenerative role in cleaning up and increasing the ecological resiliency of local ecosystems. The mycelium used in insulation products could break down pesticides and petroleum products that contaminate local ecosystems. The resulting organic compounds of the mycelium could be used for high-efficiency insulation.
The benefits of Mycelium-based insulation are profound. It could remove toxic chemicals from the environment during production and naturally decompose at the end of its useful life. And, it could enable you to avoid having your home insulated by petrochemical foam that will one day end up in landfills!
Tobias runs an agroecology farm and a natural building collective in the mountains of El Salvador. He specializes in earthen construction methods and uses permaculture design methods to integrate structures into the sustainability of the landscape.