Siwarut JullapromSorasutee BuapoolJantharat Wutisatwongkul2025-07-072025-07-072025Journal of the Korean Wood Science and Technology1017071510.5658/WOOD.2025.53.1.662-s2.0-105001964044https://repository.dusit.ac.th/handle/123456789/7304The construction industry has increasingly emphasized the importance of sustainable materials. These sustainable materials offer insights into the development of effective and ecofriendly acoustic materials. This study explored the potential of water hyacinths for sound absorption performance. An impedance tube test was conducted to analyze the sound absorption coefficient. The specimens were fabricated by spraying dried water hyacinth stalks with a polyvinyl alcohol adhesive, allowing them to dry and then cutting them into different thicknesses for measurement. A systematic analysis revealed that the sound absorption coefficients improved with increasing thickness and air-gap depth. The specimen reached its highest sound absorption coefficient value of 0.73 at 500 Hz with a thickness of 10 mm and an air gap depth of 20 mm. A greater thickness significantly enhanced the sound absorption, and additional air-gap depths further improved it. These factors correlated with higher noise reduction coefficient values (0.24 to 0.41), highlighting water hyacinth's suitability as a sound-absorbing material. Water hyacinth offers excellent sound absorption and aesthetic value. © 2025 The Korean Society of Wood Science & Technology.acoustic absorberacoustic conditioningsound absorptionsustainable materialwater hyacinthArticleScopus