The online version of the Gypsum Association’s Fire Resistance Design Manual 20th Edition 2012 is here:
The Gypsum Association’s Fire Resistance Design Manual has both proprietary and generic wall systems with fire and STC ratings. Here are some generic STC ratings of walls we always use that should help you during the design phase, the GA-WP number is the Gypsum Association number:
· 1 layer 5/8” Gypsum Board each side 3-5/8” metal studs without insulation, GA-WP-1350, 1Hr, STC 35-39
· 1 layer 5/8” Gypsum Board each side 3-5/8” metal studs with insulation, GA-WP-1072, 1Hr, STC 45-49
· 1 layer 5/8” Gypsum Board one side, 2 layers gypsum board opposite side 3-5/8” metal studs without insulation, GA-WP-1052, 1Hr, STC 44
· 1 layer 5/8” Gypsum Board one side, 2 layers gypsum board opposite side 3-5/8” metal studs with insulation, GA-WP-1052, 1Hr, STC 50-54
· 2 layers 5/8” Gypsum Board each side 3-5/8” metal studs without insulation, GA-WP-1616, 2Hr, STC 45-49
· 2 layers 5/8” Gypsum Board each side 3-5/8” metal studs with insulation, GA-WP-1522, 2Hr, STC 55-59
* The Gypsum Association’s Fire Resistance Design Manual does not have any generic wall systems with resilient furring channels, so if you need a higher STC rating you will need to go to a manufacturer’s tested system.
