- 5/8” gypsum board (type X) – 1 layer
- Sealed install2 (caulk & tape)
- STC 46 with the ceiling (lab test #NGC6015025_R1)
1 Madaras, G. and Heuer, A. (2016). “Optimizing Ceiling Systems and Lightweight Plenum Barriers to Achieve Ceiling Attenuation Class (CAC) Ratings of 40, 45 and 50”. Proceedings of the New England NoiseCon-16: Revolution in Noise Control conference, Providence, RI, 13-14 June, 2016. Electronic publication by the Institute for Noise Control Engineering.
2 The ‘sealed install’ method for the gypsum board plenum barriers is similar to fire-rated wall construction in that it includes cutting the gypsum board to within 1/4” of elements penetrating the plenum barriers. The gaps around penetrating elements, as well as small holes, joints, screw heads, perimeter edges, etc., are all taped or caulked/sealed.
3 The referenced laboratory test(s) are part of an extensive, multi-year testing program conducted by the National Research Council Canada (NRCC) and published by the Institute for Research in Construction (IRC). For more details, including 1/3 octave band transmission loss data, refer to internal reports IRC-IR-693, October 1995 and IRC-IR-761, March 1998. The research program was partially funded by ROXUL, Inc. ROCKFON and ROCKWOOL are subsidiaries of the ROCKWOOL Group.