A design team at Seoul National University’s Living Design Lab has created Re:Shell, a biodegradable material that turns discarded eggshells into functional building blocks. The project offers a sustainable response to South Korea’s rising construction waste.

From food waste to building bricks

Eggshells, rich in calcium carbonate (CaCO₃), usually end up in landfills. Re:Shell collects them from local bakeries and restaurants, grinds them into powder, and mixes the material with loess, wheat bran, and straw. This process produces a strong yet lightweight composite with adjustable textures and porosity. Unlike conventional materials, the bricks are fully biodegradable. When buried in soil, they break down naturally without leaving harmful traces.

Modular design with cultural roots

Re:Shell bricks feature an interlocking system, allowing designers to assemble them in different ways. This flexibility opens up sculptural and functional possibilities, ranging from façades and partition walls to modular furniture and mobile tables. The project draws inspiration from Korean design traditions, where adaptable spaces play a central role. By merging heritage with innovation, Re:Shell connects cultural values to modern material research.

A circular approach to construction

The project demonstrates how local waste can become a valuable building resource. By sourcing eggshells from nearby food outlets, the team reduces transport emissions and strengthens material availability. After use, the bricks return safely to the earth, supporting a closed material cycle. This circular design approach addresses both ecological concerns and the urgent need for alternatives to conventional construction products.

Expanding potential

The Living Design Lab is now testing how to improve the bricks further. Research focuses on enhancing water resistance and structural strength while keeping the material biodegradable. These developments could expand applications in both interiors and architecture.

Re:Shell shows how a simple by-product from daily life can transform into a sustainable material for future cities. By linking local resources, cultural heritage, and innovative design, it offers a clear example of how circular thinking can reshape the built environment.

Source & photos: Biodesign Challenge / Seoul National University Living Design Lab