Description

This specification covers gypsum boards which include the following:

• gypsum wallboard for use on walls, ceilings, or partitions and that affords a surface suitable to receive decoration;
• predecorated gypsum board for use as the finished surfacing for walls, ceilings, or partitions;
• gypsum backing board, coreboard, and shaftliner board for use as a base in multilayer systems or as a gypsum stud or core in semisolid or solid gypsum board partitions, or in shaft wall assemblies;
• water-resistant gypsum backing board to be used as a base for the application of ceramic or plastic tile on walls or ceilings;
• exterior gypsum soffit board for exterior soffits and carport ceilings that are completely protected from contact with liquid water;
• gypsum sheathing board for use as sheathing on buildings;
• gypsum base for veneer plaster;
• gypsum lath for use as a base for gypsum plaster application;
• and gypsum ceiling board for interior ceilings and walls.

Gypsum board shall consist of a noncombustible core, essentially gypsum, surfaced with paper bonded to the core.

The specimens shall comply with the following required physical properties:

• core, end, and edge hardness;
• straightness of the edges and ends;
• length;
• tapered edge depth;
• flexural strength;
• humidified deflection;
• nail pull resistance;
• permeance;
• water resistance;
• and surface water absorption.