For decades, our society has predominantly embraced an extractivist approach when formulating models for material manufacturing across diverse industries. While we now know that this model is unsustainable, a major question remains: So, how do we do it? We may be a while away from offering a definitive answer to this challenge. Still, it is exciting to note that, in a context marked by a challenging global and ecological horizon, the architectural community maintains a positive approach by pushing for a re-evaluation of what we make and how we make it.
This momentum may be gaining relevance due to the emergence of new, more environmentally conscious generations, such as Gen Z and Alpha. What is certain is that we are witnessing the development of new production philosophies, such as plant-based materials, which adopt practices aimed at favoring the use of resources derived from plants, reducing dependence on extractive processes, and promoting conscious and sustainable alternatives in various aspects of the manufacture and production of materials in architecture.
An outstanding advantage of plant-based materials lies in the diversity of opportunities for their development, mirroring the variety seen in nature among various species. In this context, it is worth emphasizing that a significant amount of the raw material used would normally be categorized as waste if left unused. Thus, we are witnessing the unfolding of innovative materials that contribute to the decarbonization of our environment, taking advantage of sub-explored resources that might otherwise be considered garbage.
In this context and to provide a comprehensive overview, we have carefully selected examples of plant-based materials that highlight their potential, scalability, and diverse applications within the field of architecture. Furthermore, we have gained valuable insights from experts actively involved in developing some of these innovations.
Straw-Wall Panels
The system comprises panels with a twin-stud timber frame and a straw infill mixed with other natural materials, together constituting 98% of its structure. Notably, it stands out for the absence of glues or chemicals in its production process. Overall, one of the main advantages of these straw-wall panels —developed by EcoCocon— lies in the fact that straw is obtained as a by-product of agriculture, presenting a rapidly renewable alternative compared to timber.
Currently, straw panels are employed in constructing exterior walls, offering adaptability across a spectrum of projects, ranging from single-family residences to multi-level structures, as this panel provides a load-bearing structure with high insulation levels. The system's versatility is evident in its incorporation of various panel formats crafted for specific scenarios, allowing for the fulfillment of diverse design and structural requirements.
Emphasizing the panel's ability to capture atmospheric carbon, the team is confident that modular straw construction will play a significant role in transitioning toward materials that align with environmental needs. The team states that “the key to scaling up is automation,” seeking to reduce transportation distance and embrace local production using local resources. In addition, to maintain their competitiveness in highly developed countries, they emphasize the need for small, agile, and highly automated production centers, a concept they have been developing since 2019.
Bioreceptive Concrete
This is a type of concrete with higher porosity than average, created using 90-95% recycled concrete and covered with moss wall cladding. According to Respyre, who initiated research on this material 18 years ago, the coating contains nutrients, water, and moss spores, which are sprayed onto the concrete surface. They highlight that this spraying method accelerates processes that “otherwise would happen through nature’s instinct.” This results in a material that provides benefits such as greenhouse gas conversion, promotion of biodiversity, reduction of the heat island effect, and sustainability.
To attain scalability, the team has an efficient nursery that supplies moss for projects up to 37,500 m² every 12 weeks. By outsourcing concrete production and collaborating with large-scale partners, they can operate quickly and efficiently, while focusing on moss cultivation. They stress that the main challenge lies in improving the self-sufficiency of the coating to prevent intensive project management tasks.
Overall, Respyre envisions that their research could pave the way for autonomous structures in the future, enabling the seamless integration of natural environments within urban areas. This transformation, making natural surroundings accessible in our cities, would benefit our health and the planet. Such accessibility contributes to a sustainable future by reshaping our perception of construction, turning it into a natural phenomenon rather than a human nuisance.
Fast-Growing Perennial Grass Panels
Based on only two resources —grass and formaldehyde-free resin— Plantd has crafted an alternative to oriented strand board (OSB), eliminating the “need” to cut down trees. The foundation of this material lies in addressing global warming by efficiently capturing excess carbon dioxide in the atmosphere. This is accomplished by cultivating a fast-growing perennial grass and enhancing the production process to convert it into a plant-based panel suitable for wall cladding and roof coverings.
For the team and regarding scalability, “establishing a new agricultural supply chain and designing and building proprietary manufacturing equipment is inherently challenging,” so the primary focus lies on completing a 100% electric, modular, and continuous production line. Since its founding in 2021, they have assembled a team of scientists, engineers, farmers, technicians, and storytellers who have come together to reduce carbon emissions in the built environment.
As stated by Plantd and considering the urgency of the climate crisis, “it is critical to focus on decreasing embodied carbon emissions of all new construction projects.” As such, the grass panel solution and the production of carbon-negative materials contribute to reducing embodied carbon emissions in the built environment. On a large scale, these carbon-negative materials can transform buildings from a global warming problem into a solution.
Although most building materials in architecture are associated with processes that leave a discernible carbon footprint, each innovation in plant-based materials offers new possibilities for material reuse and the decarbonization of the built environment. In the future, we are likely to witness the evolution and integration of these approaches into new constructions, giving rise to innovative and aesthetically distinct building proposals that, instead of operating on the landscape, blend in with it. These materials could serve as a foundation for a generation committed to constructing architecture that is more conscious of both what it builds and how it builds it.
