ASTM_C_442_-_C_442M_-_04e1.pdf

Designation:C 442/C 442M 04e1Standard Specification forGypsum Backing Board,Gypsum Coreboard,and GypsumShaftliner Board1This standard is issued under the fixed designation C 442/C 442M;the number immediately following the designation indicates the yearof original adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.A superscript epsilon(e)indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.e1NOTEThe word rating(s)was added to the term fire resistance throughout editorially October 2004.1.Scope*1.1 This specification covers gypsum board designed to beused as a base in multilayer systems,as a gypsum stud or corein semi-solid or solid gypsum board partitions,or in shaftwallassemblies.NOTE1Specification C 840 contains application procedures for gyp-sum backing board,gypsum coreboard,and gypsum shaftliner board.1.2 The values stated in inch-pound units are to be regardedas standard.Within the text,the SI units are shown in brackets.The values stated in each system shall be used independent ofthe other.Values from the two systems shall not be combined.1.3 The terms“backing board,”“coreboard,”and“shaftlinerboard,”refer to different end uses of the gypsum boardspecified in this specification.The term“gypsum backingboard,”in this specification,shall include gypsum coreboardand gypsum shaftliner board unless otherwise stated.1.4 The text of this specification references notes andfootnotes which provide explanatory material.These notes andfootnotes(excluding those in tables and figures)shall not beconsidered as requirements of the specification.2.Referenced Documents2.1 ASTM Standards:2C 11 Terminology Relating to Gypsum and Related Build-ing Materials and SystemsC 473 Test Methods for Physical Testing of Gypsum PanelProductsC 645 Specification for Nonstructural Steel Framing Mem-bersC 840 Specification for Application and Finishing of Gyp-sum BoardC 1264 Specification for Sampling,Inspection,Rejection,Certification,Packaging,Marking,Shipping,Handling,and Storage of Gypsum BoardE 84 Test Method for Surface Burning Characteristics ofBuilding MaterialsE 96 Test Methods for Water Vapor Transmission of Mate-rialsE 119 Test Methods for Fire Tests of Building Constructionand Materials3.Terminology3.1 DefinitionsDefinitions of terms shall be in accordancewith Terminology C 11.3.2 Definitions of Terms Specific to This Standard:3.2.1 gypsum backing board,na14to58-in.6.4 to15.9-mm gypsum board used as a backing for gypsumwallboard,acoustical tile,or other dry cladding.3.2.2 gypsum coreboard,na34or 1-in.19.0 to 25.4-mmgypsum board used as a gypsum stud or core in semisolid orsolid gypsum board partitions.3.2.3 gypsum shaftliner board,na34or 1-in.19.0 or25.4-mm gypsum board used in shaftwall assemblies.4.Materials and Manufacture4.1 Gypsum backing board shall consist of a noncombus-tible core,essentially gypsum,surfaced with paper bonded tothe core.4.2 Gypsum coreboard is a single34-in.19.0-mm or 1-in.25.4-mm thick board or is composed of two factory lami-nated boards to provide34-in.19.0-mm or 1-in.25.4-mmtotal nominal thickness.4.3 Gypsum shaftliner board is a single34-in.19.0-mm or1-in.25.4-mm thick board.4.4 Foil-backed gypsum backing board shall consist ofgypsum backing board with a layer of aluminum foil laminatedto the back surface.1This specification is under the jurisdiction of ASTM Committee C11 onGypsum and Related Building Materials and Systems and is the direct responsibilityof Subcommittee C11.01 on Specifications and Test Methods for Gypsum Products.Current edition approved Jan.1,2004.Published January 2004.Originallyapproved in 1959.Last previous edition approved in 2001 as C 442 01.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959,United States.NOTICE:This standard has either been superseded and replaced by a new version or withdrawn.Contact ASTM International(www.astm.org)for the latest information 4.5 Gypsum Backing Board,Type X(Special Fire-Resistant):4.5.1 Gypsum backing board,type X,designates gypsumbacking board,except gypsum coreboard and gypsum shaft-liner board,complying with this specification that provides notless than 1-h fire resistance rating for boards58-in.15.9-mmthick or34-h fire resistance rating for boards12-in.12.7-mmthick,applied parallel with and on each side of load bearing 2by 4 wood studs spaced 16-in.406-mm on center with 6dcoated nails,178-in.48-mm long,0.0915-in.2.3-mm diam-eter shank,14-in.6.4-mm diameter heads,spaced 7-in 178-mm on center with gypsum backing board joints staggere