The estimation of the precision of the apparent dynamic stiffness measurement method was analysed by means of an interlaboratory experiment. The same three samples of three different closed cell materials and three samples of three different open cell materials have been sent to 10 laboratories. They were tested rigorously according to one of the two main methods described in the standard EN 29052-1: white noise or pulse signals. A plaster layer was applied on each sample with a drying period of 1 hour and a vaseline contour was applied only for the closed cell materials. The analysis of the results was carried out according to the guidance of the standard ISO 5725-2. Some laboratories have also measured the airflow resistivity.