Sustainable Construction: Revitalizing Traditional Building Materials

The global construction industry is rediscovering traditional, renewable building materials—including wood, earth, and straw—as part of a broader effort to establish a low-emissions future. This shift comes as the sector seeks alternatives to concrete and steel, which are associated with high climate costs.

According to Guillaume Habert, a Professor of Sustainable Construction at ETH Zurich, materials derived from renewable resources produce significantly fewer greenhouse gas emissions. This represents attributed to the natural carbon cycle of these materials.

As these resources grow, they absorb CO2 from the atmosphere – and when they are used in construction materials, that carbon remains locked away for the long term.

Guillaume Habert, Professor of Sustainable Construction at ETH Zurich

The Use of Earth and Local Soil

One primary example of this return to traditional materials is the use of earth. In Switzerland, approximately 50 million tonnes of soil are excavated annually during the construction of buildings and homes. Historically, the majority of this material has been sent to landfills.

Researchers suggest that utilizing clay-rich soil as a building material allows the industry to close the resource loop at its source. This approach reduces the number of lorry journeys required to transport waste and saves money for builders who otherwise pay to have excavated material removed.

The potential for earthen structures is demonstrated by the kiln tower at the Brickworks Museum in Cham, which is recognized as the world’s first prestressed earthen structure, reaching a height of nearly nine metres.

Health and Economic Impacts

The transition toward natural building materials is linked to benefits beyond carbon reduction. Studies indicate that these materials can improve occupant health by reducing the prevalence of asthma and allergies.

prioritizing local, natural resources supports local economies by reducing dependence on imported industrial materials and lowering transportation costs.

Sustainable Material Alternatives

Beyond earth and straw, other renewable materials are gaining traction for their specific physical properties and environmental profiles.

• Bamboo: Recognized for its fast growth rate—up to 1.5 inches or 3.8 centimeters per day—bamboo is found on every continent except Europe and Antarctica. It is valued for its flexibility and a high strength-to-weight ratio, making it an economical choice for global projects.
• Cork: Harvested from the cork oak tree, cork is a renewable material because the bark can be harvested without harming the tree. It is waterproof, resistant to abrasion, and fire-retardant. Due to its insulation capacities, its use in internal and external cladding is increasing.
• Hempcrete and Mycelium: These are identified as other top sustainable materials for eco-friendly construction, alongside recycled glass and precast concrete.

Environmental Adaptability and Culture

The choice of building materials has historically been driven by resource availability, climate, and culture. Examples include the use of complex adobe structures in Western Africa, wood paneling in rural Finland, and red-brick houses in suburban United States centers.

However, the increasing replacement of these traditional materials with modern alternatives has often resulted in a loss of environmental adaptability. Research indicates that overlooking the sustainability of traditional materials has led to missed opportunities for improving energy efficiency and reducing carbon emissions.

As the industry focuses on reducing embodied carbon emissions—the carbon footprint associated with the manufacturing, transportation, and installation of materials—the integration of these traditional, renewable resources is becoming a central strategy for sustainable architecture.