"Unless otherwise specified, the face layers of all systems, except those with predecorated or metal covered surfaces, shall have joints taped (minimum Level 1 as specified in "GA-214, Recommended Levels of Gypsum Board Finish") and fastener heads treated. Base layers in multi-layer systems shall not be required to have joints taped." [Note 6]
"When a fire-resistance rated partition extends above the ceiling, the gypsum board joints occurring above the ceiling need not be taped and fasteners need not be covered when all of the following conditions are met: (a) The ceiling is part of a fire-resistance rated floor-ceiling or roof-ceiling system; (b) All vertical joints occur over framing members; (c) Horizontal joints are either staggered 24 inches o.c. on opposite sides of the partition, or are covered with strips of gypsum board not less than 6 inches wide; or the partition is a two-ply system with joints staggered 16 inches or 24 inches o.c.; and (d) the partition is not part of a smoke or sound control system. Where joint treatment is discontinued at or just above the ceiling line, the vertical joint shall be cross taped at this location to reduce the possibility of joint cracking." [Note 7]
Obviously, this material is a bit stiff and not the kind of information one would expect to find in a slick promotional brochure, but these are three of the 22 notes found in the general explanatory notes section of the FRDM, all of which answer routine questions that arise in the construction of fire-resistance and sound-rated construction. Getting familiar with this manual will go a long way toward understanding the concepts used to create fire-resistant and sound-attenuating gypsum-based building systems.
To further make the information in the FRDM more accessible to its users, we are in the final stages of producing an internet-accessed program that will familiarize viewers with the several sections of the manual, show them how to quickly find the relevant material, and allow them to earn AIA continuing education units.
For more than 75 years, the Gypsum Association has sought to provide the design and code communities with information that enables them to create safer, more comfortable environs, and we're proud that "GA-600, Fire Resistance Design Manual," is one of the main vehicles for imparting that information.
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