Effect of the finishing on the sound absorption characteristic of a mineral wool

Sometimes, mineral wool cannot be used ’as it is’ for civil applications but needs some type of finishing. In this work, a test case is analysed where a mineral wool ceiling was finished using a paint suggested by the company producing the material. The reverberation time of the room before painting the ceiling was suitable for the destination of the room. On the other hand, when the wool was painted, the reverberation time, and the acoustics of the room in general, resulted to be unsatisfactory. This research aims to characterise the material before and after being painted. The measurements on the material were performed using a four-microphone impedance tube.