FOCUS ON NATURAL MATERIALS
Photo: Tommaso Riva
THE BUILDING INDUSTRY, ONCE FUELLED BY CHEMICALLY ENGINEERED MATERIALS, IS NOW FACING THE ENVIRONMENTAL CONSEQUENCES OF ITS OWN RAPID GROWTH. ARCHITECTS REALISE THEY HAVE A KEY ROLE TO PLAY IN THE TRANSITION TOWARDS A SUSTAINABLE FUTURE. THEIR GAZE IS LOOKING TOWARDS NATURE FOR INSPIRATION, WITH BIO-BASED MATERIALS USHERING IN A NEW ERA OF HEALTHIER, ENVIRONMENTALLY-FRIENDLY CONSTRUCTION. WOOD IS SHAPING THE SKYLINES OF TOMORROW, WHILST EXPERIMENTAL MATERIALS SUCH AS FUNGI AND SALT ARE EXPANDING THE INDUSTRY’S HORIZON.
The building industry has historically relied on chemically produced materials. Progress led to an ever-increasing appetite for synthetics and complex, reinforced concrete structures. Cities grew higher, better, faster, stronger, but the long-term cost of these materials has since become apparent. According to the United Nations Environment Programme, the building industry nowadays accounts for a staggering 40% of global CO2 emissions, with about 10% stemming from the materials applied. Architects are now driving the industry forward in a more sustainable direction.
Choosing healthy, sustainable materials
The use of bio-based materials is on the rise amongst designers. Wood, earth, flax, and hemp: many century-old, natural products are rapidly coming back in vogue. Studies show that they create a better indoor climate and even have the potential to reduce stress for its users. Amongst all bio-based materials, wood especially is undergoing a true renaissance as the construction material of choice. In addition to its much lower environmental impact and health benefits, wood offers an additional bonus: trees sequester CO2 from the atmosphere during their growth from seedling to tree, actively contributing to the fight against climate change. Wooden skyscrapers, up to a hundred meters, are now popping up around the globe having been made possible by high-tech production processes. Engineered timber options, such as cross-laminated timber (CLT) and laminated veneer lumber (LVL) meet modern demands for fire safety and durability.
Farm-to-table architecture But the renewed interest in natural materials is not limited to the use of wood. Some architects translate their eco-conscious purpose into an expanded material repertoire. Earth, wool and even salt and fungi create surprising designs to inspire the next generation of architects. Some go even further – seemingly drawing inspiration from the culinary world’s Slow Food movement – by choosing locally grown flax or hemp, they reduce transport costs and support local growers. Farm-to-table architecture is now on the menu.
THE ARC AT GREEN SCHOOL Sibang, Indonesia
Natural materials have traditionally been tied to their growth regions. In forested areas, wood was the material of choice; near rivers, clay was used for bricks. In tropical regions, it has always been bamboo. As a crop, it grows from seed to full-grown plant in just four years, making it affordable and highly efficient. Additionally, it can be engineered into a strong structural element. However, unlike other region-specific materials, bamboo has not yet gained widespread use outside tropical areas as a load-supporting material. But now as the demand for bio-based materials increases, bamboo is finally receiving the worldwide recognition it deserves. The Arc, a multifunctional space in Bali designed for outdoor sports and gatherings, has gone viral as a showcase for its possibilities. It has captured the imagination of architects and builders around the globe, as evidenced by its many international awards.
Bamboo as a building material The Arc is part of the Green School in Bali, a private educational institution focused on sustainability. The school’s curriculum emphasises hands-on learning, from making surfboards from bottle caps to regenerating coral reefs. The Arc’s design reflects the school’s philosophy, providing an optimistic space for students to engage. Crafted by Jörg Stamm and the architecture office Ibuku, both specialists in bamboo, the building was designed in close collaboration with Atelier One’s engineers. One key property of bamboo makes it specifically ideal for this project: its malleability. The design team collaborated with local craftsmen to use its ability to curve and bend to create a structure that flows and blends fluidly into its natural surroundings.
A structure like a mammal’s chest The design evokes the shapes of the natural world, and the architects aptly describe the structure of the building like a mammal’s chest; an inner ribcage consisting of bones, combined with outer ‘muscles’ and ‘skin’ that form a protective layer around the torso. The inner structure is composed of bamboo beams spanning fourteen meters in height and nineteen meters in length, supported by concrete foundations. Together, they create the building’s recognisable shape of five central arches, with one smaller supporting arch that creates a wing at each end. Covering the structure are large surfaces of bamboo shingles. They playfully curve in- and outward within their individual roof sections, creating the necessary tension to hold the inner structure in place.
Architect: Ibuku
The roof sections playfully curve in- and outward, creating the necessary tension to hold the inner structure in place.
PHOTO: TOMMASO RIVA
A whimsical showcase of bamboo engineering
PHOTO: TOMMASO RIVA
PHOTO: TOMMASO RIVA
STEIRERECK TREEHOUSES Pogusch, Austria
The application of cross-laminated timber (CLT) is gaining momentum throughout the world. As a building material, CLT has proven itself as a technically advanced, lightweight and fire-resistant powerhouse that is particularly suited to prefabricated construction methods. Factories produce standardised modules as building kits that can be shipped and put together on site. It’s environmentally-friendly, cost-effective and leaves little room for errors on site. However, there has been some backlash from the architecture community due to its repetitiveness. Does this efficiency-driven trend leave any space for the architect as a visionary designer? Or can technology and imagination reach new heights together?
Bright-eyed structures hidden amongst the trees Studio Precht demonstrates that engineered timber is a much more versatile material – than one might assume – that holds plenty of potential for the imagination. For a historic inn at Pogusch in Austria, the studio created four treehouses that have an almost cartoon-like appearance. The large, circular windows give the buildings the look of a one-eyed Minion, seemingly eager to lock eyes with whoever discovers them amongst the trees. Each treehouse is built up around a simple structure, resting on a discreet concrete foundation. There, a few intersecting stacked wooden tubes are covered in traditional wooden shingles. The central vertically placed tube functions as the circulation space, whilst out-branching horizontal tubes furnish the living spaces with windows or balconies at the ends.
Constructed in only a few days Even though the buildings seem custom-made, they are the result of modular, prefabricated construction techniques using CLT. Studio Precht created the design in collaboration with a tiny-homes startup in 2019, intended to create a building with a small footprint to minimise ecological impact. Each treehouse combines standardised pieces from a catalogue of curvy, modular wooden elements that client and architect created together. After choosing the preferred combination of pieces, they were produced in a factory and assembled on site. The assembly had a quick learning curve: the first treehouse took about seven days to complete, while the last one was done and dusted within the span of one day. These architectural forest dwellers prove that modular construction with CLT can be efficient and simultaneously as wild as a child’s imagination.
Architect: Studio Precht
The large, circular windows give the buildings the look of a one-eyed Minion, seemingly eager to lock eyes with whoever discovers them amongst the trees.
Combinding imagination and prefabrication
RWANDA INSTITUTE FOR CONSERVATION AGRICULTURE Gashora, Rwanda
An architect’s choice of building material goes beyond environmental considerations. It can reflect broader cultural, financial, societal, and political values. Some architects, like MASS Design Group, adopt a holistic approach by selecting materials that promote positive impacts across all these areas. MASS, a Rwanda and U.S.-based nonprofit, comprises over 200 international architects, engineers, writers, and researchers. Their mission is “to research, build, and advocate for architecture that promotes justice and human dignity.” The design for the Rwanda Institute for Conservation Agriculture (RICA) campus shows how they put this mission into practice.
A new type of campus for agricultural entrepreneurs The Rwanda Institute for Conservation Agriculture is a newly established university located near Gashora, Rwanda. It trains students in the principles of sustainable agriculture and conservation practices. Due to the agricultural curriculum, the campus program includes animal and plant-focused farms, a water treatment facility and efforts to preserve two nearby savannah zones along with a papyrus wetland buffer. In total, the campus consists of more than sixty-nine buildings. One architectural highlight is the accommodation for second and third year students constructed in the shape of a figure eight swerving around two circular courtyards. The whole campus is off-grid, powered by energy generated by an on-site solar farm. Throughout the campus, the architects applied passive design principles, prioritising natural ventilation to minimise the need for technical installations.
Impact on the local community and even national policies MASS worked in close collaboration with the local community and RICA specialists. About 95% of the workers were hired from the region and over three hundred people received on-site training in sustainable construction methods. Local artisans created the furniture and fittings used throughout the campus. RICA incorporated biogenic and low-impact materials and leveraged the construction process for training and job creation in regenerative practices. The structures, located in a seismic zone, utilise stone foundations, compressed earth brick walls, and wood roofs to reduce embodied carbon by 60%, support regenerative material industries, and demonstrate replicability.
Architect: MASS Design Group
During the building of the campus, over 300 workers received training in sustainable construction methods.
PHOTO: MASS DESIGN GROUP
PHOTO: IWAN BAAN