1.1 This specification covers the minimum requirements for and methods of application of exterior gypsum panel products that are specifically designed for use as a substrate for exterior cladding. 1.1.1 This specificatio This specification covers the minimum requirements for and the methods of application of gypsum sheathing for use as a substrate for exterior wall cladding. Gypsum sheathing board is a substrate that shall be covered by an exterior cladding or other we