American Gypsum's 1" M-Bloc Shaft Liner gypsum panels consist of a fire-resistant type X core that is encased in a mold and moisture resistant blue face and back paper manufactured from 100% recycled paper. The face paper is folded around the long edges to reinforce and protect the core. The panels feature a double beveled edge for ease of installation, with the ends being square-cut and finished smooth. M-Bloc Shaft Liner panels are available: 1" thick x 2' wide, and in a variety of lengths. At an independent laboratory accredited in accordance with ISO 17025-2005, M-Bloc panels have been tested to the industry s most rigorous standards achieving the best possible results per ASTM D3273, scoring a perfect 10 thus minimizing the risk of mold and mildew growth.

Basic Uses

M-Bloc Shaft Liner panels are used in conjunction with other American Gypsum products and metal framing members for Shaftwall and Area Separation Wall systems. M-Bloc Shaft Liner may be substituted for American Gypsum's standard 1" Shaft Liner panels. Lightweight non-load bearing gypsum Shaftwall systems have replaced traditional masonry for interior vertical enclosures including stairwells, elevator enclosures and mechanical chases.

American Gypsum's M-Bloc Shaft Liner has been approved for use in the following assemblies

• U375 - 2 Hour H-Stud Area Separation Wall System
• V455 - 1 & 2 Hour Shaftwall Systems using I, C-H and C-T Studs
• U428 - 2 Hour Shaftwall System using C-H and C-T Studs
• U429 - 2 Hour Area Separation Wall System using C-H and C-T Studs
• V433 - 2 Hour Shaftwall System using I-Studs