Sound absorption properties of reed

The use of reed (Phragmites australis) as building material is common in many countries all over the world. This material was especially employed in lowlands regions, thanks to its abundance and good performance related to thermal and hygrometric comfort. Today the use of reed is not widespread and limited to some applications in green architecture, especially as thermal/sound insulating materials in roofs and walls, both as internal or external insulation covered with plaster. The scope of the present paper is to study the sound absorption properties of reeds using an impedance tube according to ISO 10534-2. Several samples were tested in order to study the influence of the manufacturing process, for instance the thickness and the spatial configuration (reeds parallel or perpendicular to the sound wave). The results show that, if properly designed, reed panels can represent a sustainable and low cost alternative to common absorbers.