Thank you for your information. Unfortunately, the gypsum by itself does not provide the official hourly rating. Mainly because this is a horizontal assembly. If I can prove that the steel, by itself or in a tested situation, can stand- then i have something.
I have a situation where 18 gauge 2x6" steel studs have been used as ceiling joists with 5/8" type 'X' gyp. bd. both sides. I am unable to find a verifiable hourly rating for this assembly. UL only has floor or roof assemblies. Is there any web sites, or printed info. regarding such...
