Chow to Wow: Transforming Luffa Sponges and Spent Coffee Grounds into Sustainable Furniture

In response to the growing food waste issue exacerbated by increased online food delivery services during the COVID-19 lockdowns, the Luffa Stoolita explores the potential of plant-based by-products as alternative materials for design and construction. This design serves as a symbol of responsible consumption and low-impact solutions to address food waste.

Columbia University GSAPP master’s students Justin Wan, Paul Edward Liu, and Tim Ting-Hao Chen spearheaded the project, aiming to harness the physical attributes of the luffa fruit to enhance the structural integrity of earth-based designs. By repurposing plant-based by-products and their residual waste, the design showcases the potential to extend the life cycle of food beyond its fleeting period of consumption. Emphasizing environmental consciousness, all materials used in the project are locally sourced.

Under the guidance of Columbia University GSAPP Professor Lola Ben Alon, the team focused their research on the combined application of luffa sponges, spent coffee grounds, and clay-rich soil as aggregate and binding agents to craft the stool design. Experimentation involved blending coffee aggregates, shredded luffa, and earth as a binding agent to create composite materials capable of withstanding stress without crumbling. Given the project's core concept of using food waste for design without generating additional waste, all parts of the luffa fruit are utilized in each component of the furniture piece.

Leveraging the luffa's inherent tensile properties, the team engineered the legs from halved luffa segments. Acting as formwork, the luffa segments are filled with the identified earth-coffee blend, each time in thin layers and tamped to ensure proper compaction. The seat base is made from a similar earth blend, mixed with shredded luffa as a reinforcing material to control shrinkage and provide flexibility. The cushion, crafted from the outer surface of the luffa fruit, is turned inside-out to reveal a smoother surface, offering enhanced comfort. Additionally, the design exposes intricate patterns where the seeds were once nestled. The cushion is carefully affixed to the seat base while the latter is still damp, followed by thorough drying to ensure optimal adhesion. The material combination results in a sturdy and compact design that fuses the lightweight and rigid structure of the luffa with the strength and heftiness of earthen materials.

This eco-conscious creation challenges the norms of furniture design, demonstrating the feasibility of using luffa fruit for load-bearing purposes at the human scale. Standing 240mm tall with a 315mm diameter, the Luffa Stoolita embodies the ethos of responsible consumption and sustainable design, offering a tangible solution to combat food waste and promote environmental stewardship.