Corn Husk Fiber Composite as a Noise Reducer for Galvalume Roofs

Galvalume roofing, widely used for its durability and cost-efficiency, often generates significant noise during rainfall, impacting indoor acoustic comfort. This study aims to evaluate the impact of incorporating corn husk f ibre on the effectiveness of noise reduction through epoxy matrix-based composite coatings on galvalume roofs. Applying a sound-dampening layer on the surface of galvalume roofing is expected to reduce the noise level generated, especially during rainfall. The composite used as a coating consists of natural fibres—in this case, corn husk fibres—which serve as the filler material to support the soundproofing function. The samples used in this study are galvalume roof panels coated with a composite material, which were tested through simulated artificial rainfall and measurements using a sound absorption coefficient testing device. The coating process was carried out using the hand lay-up method, with a mixture of epoxy resin and corn husk fibres in varying weight fractions: 0 %:100 %, 20 %:80 %, 30 %:70 %, 40 %:60 %, and 50 %:50 %. Based on macroscopic observations of fibre distribution, the 50 %:50 % weight fraction showed the most even distribution, with a uniformity rate of up to 93 %. In noise level testing, the 50 %:50 % composition resulted in the lowest recorded noise level of 74 500 dB. The sound absorption coefficient test was conducted by placing the specimen in a rectangular testing chamber measuring 100 cm × 50 cm × 50 cm, equipped with two sound level meters. The results showed the lowest absorption coefficient (α = 0,3695 cm) at the 20 %:80 % fraction and the highest (α = 0,6365 cm) at the 50 %:50 % fraction. Overall, the study concludes that increasing the content of corn husk fibre significantly influences the effectiveness of noise reduction on galvalume roofs.