Does SoundStop® diminish the one hour wall system fire rating?
No. Tests conducted by the Gypsum Association report wood fiberboard does not diminish wall system fire ratings. This is documented in the Gypsum Association’s 14th Edition of the Fire Design Manual – GA File WP 3330 and WP 3510. These observations are further described in the ASTM Special Technical Publication STP 685 Ten Rules of Fire Endurance. The Uniform Building Code addresses the fire resistance of walls via footnote 14 to Table 7-B.
