The material research at the University of São Paulo, which began with a workshop, is now in the monitoring phase – evaluating how the banana tree fiber boards have held up over the past month.
In an effort to simulate extreme climatic conditions, the boards were placed in an enclosed room with little ventilation. Because of the humid subtropical climate of São Paulo, they had become moldy, and layers had begun to pull apart. How the boards fared seemed to depend on what kind of glue was used and the number of layers.
Boards were created in 3, 4, 5, and 6-ply thicknesses, and were glued with a cassava starch-based adhesive, wheat flour glue, or a combination of both. Overall, the 3 and 4-ply boards held together well, showing minimal mold, while the thicker ply boards began to separate, in addition to showing clear signs of mold.
The moldiness could be caused by the combination of several factors: as mentioned, the testing environment was not well ventilated; it had been raining when the boards were created; and the weather humid. The team determined that it may be necessary to dry the boards in an oven if the weather conditions do not allow them to dry completely.
More testing is needed to create a stable and durable material. Research into other combinations of glue and waterproofing materials will continue at the University of São Paulo.
All photos by Larissa Delanez.
Architecture for Humanity and Alcoa Foundation have come together to support the realization of community-based projects that explore innovations in design, materials and building systems.