ASTM_C_844_-_15.pdf

Designation:C84415Standard Specification forApplication of Gypsum Base to ReceiveGypsum Veneer Plaster1This standard is issued under the fixed designation C844;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S.Department of Defense.1.Scope1.1 This specification covers the minimum requirements for,and methods of,application of gypsum veneer base for gypsumveneer plasters.1.2 Gypsum veneer base shall not be used as a base fordirect adhesive application of ceramic,metal,or plastic tile inareas exposed to abnormal moisture or humidity or tempera-ture.1.3 Details of construction for a specific assembly toachieve the required fire resistance shall be obtained fromreports of fire-resistance tests,engineering evaluations,orlistings from recognized fire testing laboratories.1.4 Where a specific degree of sound control is required forveneer plaster assemblies and constructions,details of con-struction shall be in accordance with official reports of testsconducted in recognized sound testing laboratories in accor-dance with the applicable sound tests,Test Methods C423,E90,or E492.1.5 Where this specification is more stringent(size orthickness of framing;spacing of fasteners)than the fire-ratedconstruction,this specification shall govern;otherwise,theconstruction described in the fire test report shall govern.1.6 Unheated spaces above gypsum veneer base ceilingsshall be properly ventilated(see Appendix X3).1.7 The values stated in inch-pound units are to be regardedas the standard.The SI(metric)values given in parentheses areapproximate and are provided for information purposes only.1.8 The text of this standard references notes and footnoteswhich provide explanatory material.These notes and footnotes(excluding those in tables and figures)shall not be consideredas requirements of the standard.2.Referenced Documents2.1 ASTM Standards:2C11 Terminology Relating to Gypsum and Related BuildingMaterials and SystemsC423 Test Method for SoundAbsorption and SoundAbsorp-tion Coefficients by the Reverberation Room MethodC514 Specification for Nails for the Application of GypsumBoardC587 Specification for Gypsum Veneer PlasterC754 Specification for Installation of Steel Framing Mem-bers to Receive Screw-Attached Gypsum Panel ProductsC954 Specification for Steel Drill Screws for theApplicationof Gypsum Panel Products or Metal Plaster Bases to SteelStuds from 0.033 in.(0.84 mm)to 0.112 in.(2.84 mm)inThicknessC955 Specification for Load-Bearing(Transverse andAxial)Steel Studs,Runners(Tracks),and Bracing or Bridgingfor Screw Application of Gypsum Panel Products andMetal Plaster BasesC1002 Specification for Steel Self-Piercing Tapping Screwsfor Application of Gypsum Panel Products or MetalPlaster Bases to Wood Studs or Steel StudsC1007 Specification for Installation of Load Bearing(Trans-verse and Axial)Steel Studs and Related AccessoriesC1047 Specification for Accessories for Gypsum Wallboardand Gypsum Veneer BaseC1396/C1396M Specification for Gypsum BoardC1546 Guide for Installation of Gypsum Products in Con-cealed Radiant Ceiling Heating SystemsE90 Test Method for Laboratory Measurement of AirborneSound Transmission Loss of Building Partitions andElementsE492 Test Method for Laboratory Measurement of ImpactSound Transmission Through Floor-Ceiling AssembliesUsing the Tapping Machine1This specification is under the jurisdiction of ASTM Committee C11 onGypsum and Related Building Materials and Systems and is the direct responsibilityof Subcommittee C11.03 on Specifications for theApplication of Gypsum and OtherProducts in Assemblies.Current edition approved April 1,2015.Published April 2015.Originallyapproved in 1978.Last previous edition approved in 2010 as C844 04(2010).DOI:10.1520/C0844-15.2For 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.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 2.2 American Softwood Lumber Standard:PS20 American Softwood Lumber Standard33.Terminology3.1 Definitions:3.1.1 Definitions shall be in accordance with TerminologyC11.3.2 Definitions of Terms Specific to This Standard:3.2.1 base ply,nfirst ply of gypsum base in multiple plyapplication.3.2.2 face ply,nouter or visible layer of gypsum base inmultiple ply application.3.2.3 fastener,nnails,screws,or staples used for theapplication of the gypsum base or backing board.3.2.4 framing member,nthat portion of the framing,furring,blocking,and so forth,to which the gypsum base isattached.Unless otherwise specified,the sur