Start with the building and floor construction, not with a single advertised acoustic number. Dunlop's acoustic guidance notes that every building is different and that site information is needed to interpret impact-sound results properly. The same underlay can perform differently over concrete, timber or other floor systems, and the finished result also depends on the carpet and installation. For an upstairs room, apartment or strata project, identify the required acoustic target first, then compare test data for a flooring system that is relevant to that construction and confirm the proposed specification with the installer, building manager or other responsible party where required.
