Cutting Through the Noise on WALL CONSTRUCTION

摘要

To reiterate, privacy is a continuum, and not a sharp division as shown in Figure 1. Informed judgment is an essential part of providing the degree of privacy expected by the occupants of the multifamily housing. Persons moving to a condominium from a private residence may require more privacy than someone who has lived previously in a multifamily environment. Obviously, the larger the area of a wall between two rooms, the more acoustical power will be transmitted from one space to the other. So, to better compare the properties of two walls, a correction must be made for the relative wall areas. Also, the more acoustical absorption in the receiving room, the more transmitted sound is absorbed, thus lessening the noise level in the space. A correction for the absorption must also be made to compare two wall constructions. To fully complete the picture, other similar measures such as NR and NIC are used. All STC and ASTC tests start out with the same basic measurements—the numerical difference between the sound level (in decibels) on the noise-source side of the wall and the noise-receiver side of the wall. For NC and NIC, no correction is made for common wall area or acoustical absorption in the receiving room. This difference is acoustical noise reduction.