Comparative study on the efficiency of impact sound reduction provided by same materials when disposed on homogeneous and on non-homogeneous floors

Abstract

From the acoustical point of view, the main purpose of floor coverings and/or floating floors is to reduce the impact noise of the bare floor, in order to normally comply with national regulations. It is widely known that the acoustic behaviour of homogeneous and heterogeneous floors differ significantly, mainly due to their structural properties. In this regard, when proposing materials or systems to reduce the impact sound transmission a doubt arises: same materials behave similarly in both types of floors? In this study, laboratory tests of impact sound insulation were carried out in order to study the acoustic performance of the same materials when disposed on homogeneous and nonhomogeneous floors. Four types of materials commonly used in Spain and Portugal, were considered. The acoustic characteristics of these materials were also investigated to compare the efficiency of those materials on the basis of using their dynamic or static stiffness. The two type floors selected for the tests were: i) a heavyweight concrete slab (14 cm thick), and ii) a prefabricated lightweight floor composed of two panels of recycled materials bonded with thermosetting resins, with a chamber filled with panels of XPS. Based on the work done, some important results were obtained and relevant conclusions were extracted, which ones could help to better evaluate the efficiency of impact sound reduction systems in accordance with legal regulations and applied standards.