Assessment of footstep noise through wood-joist and concrete floors

摘要

A technique for rating floors for impact-sound insulation by subjective comparisons of the sounds of transmitted footsteps is described. The subjective judgements were used as a criterion for checking objective ratings obtained with the standard ISO impact machine. A previous study was done in the laboratory on variations of a reinforced concrete-slab floor. Further observations have now been made in typical buildngs, with special attention to wood-joist floors. For the whole study, the correlation between subjective and machine ratings is limited in range if the usual shape of reference contour, adopted for example by the U.S. Federal Housing Administration, is used. This contour makes the results, especially for hard-surfaced concrete floors, dependent on high-frequency noise that is characteristic of the machine rather than of actual footsteps. A better correlation is obtained by changing from the present FHA reference contour to one that reduces the emphasis on high frequencies.