Sound transmission loss of lightweight double walls filled with polyurethane foam

This paper presents measured sound transmission loss (TL) data for double walls with cavities filled with polyurethane foam. Experimental results illustrating the influence of polyurethane foam bulk density and thickness on sound transmission loss are presented and discussed. The results obtained suggest that the low-frequency TL of a lightweight, double-stud wall can be increased by filling in the stud cavities with polyurethane foam. For the ranges of foam density and thickness tested, there was no significant increase in low-frequency TL observed with either increasing foam thickness or density. (C) 2000 Institute of Noise Control Engineering.