Speaker
Description
The acoustic behaviour of multilayer wallpaper made from hemp stalk and rice straw is investigated in this study. The work was developed from a broader study on bio-based interior materials, but the present paper focuses on acoustic performance. The proposed wallpaper consists of a porous core layer based on hemp–straw mixtures and a surface layer made of Xuan paper, jute fabric, and dried botanical elements. Samples with different hemp–straw ratios and different thicknesses were prepared under controlled conditions to examine the influence of material composition and specimen thickness on sound absorption. The normal-incidence sound absorption coefficient was measured by means of an impedance tube over the frequency relevant to interior environments such as hotel rooms and bedrooms. The measurements show that the wallpaper provides sound absorption in the speech-frequency range, and that the acoustic response changes with both thickness and fiber composition. The results suggest that bio-based wallpaper can be considered not only as a decorative wall finish, but also as a functional interior layer with acoustic value.