ASTM_C_847_-_14a.pdf

Designation:C84714aStandard Specification forMetal Lath1This standard is issued under the fixed designation C847;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.Scope*1.1 This specification covers sheet lath,expanded metallath,diamond mesh,flat and self-furring,and rib metal lath,18and38in.(3.2 and 9.6 mm),all with or without backing anddesigned to be used as a base for gypsum or portland cementplaster.1.2 The values stated in inch-pound units are to be regardedas standard.The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.2.Referenced Documents2.1 ASTM Standards:2A653/A653M Specification for Steel Sheet,Zinc-Coated(Galvanized)or Zinc-Iron Alloy-Coated(Galvannealed)by the Hot-Dip Process3.Material3.1 Metal lath shall be fabricated from cold-rolled carbonsteel sheet of commercial quality conforming to SpecificationA653/A653M.Galvanized metal lath shall have a G60 coatingin accordance with Specification A653/A653M.3.2 Backing shall be attached to the lath sufficiently enoughto prevent accidental removal during shipping,handling,orinstallation.Attachment of backing shall also allow lapping ofmetal to metal and backing to backing,1 in.(25.4 mm)on theends and12in.(12.7 mm)on the sides.4.Dimensions,Mass,and Permissible Variations4.1 ThicknessThe nominal thickness of diamond meshand flat rib metal lath shall be18in.(3.2 mm).The nominalthickness of other rib metal lath shall be as designated,38in.(9.6 mm).The nominal thickness of self-furring diamond meshshall be516in.(7.9 mm).4.2 WidthThe minimum width of metal lath shall be 27 in.(686 mm).4.3 LengthThe minimum length of metal lath shall be97 in.(2464 mm).4.4 WeightThe weight of metal lath shall be as follows:4.4.1 U.S.Weights:Type:Weight,lb/yd2(kg/m2)Diamond mesh2.5(1.4);3.4(1.8)Flat rib1.8(1.0);2.75(1.5);3.4(1.8)38-in.rib3.4(1.8);4.0(2.1)4.4.2 Canadian Weights:Type:Weight,lb/yd2(kg/m2)Diamond mesh2.5(1.4);3.0(1.6);3.4(1.8)Flat rib1.8(1.0);2.5(1.4);3.0(1.6)38-in.rib3.0(1.6);3.5(1.9);4.0(2.1)4.5 Permissible VariationsThe permissible variationsshall be as follows:4.5.1 Thickness,6164in.(0.4 mm).4.5.2 Width,0 in.,+38in.(9.5 mm).4.5.3 Length,0 in.,+112in.(38.1 mm).4.5.4 Weight,610%.5.Finish5.1 Metal lath shall be fabricated from hot-dipped galva-nized steel.6.Weight Test6.1 Significance and UseThis test method provides aprocedure for measuring the weight of a single sheet of metallath.It shall be used to determine compliance with thisspecification.The degree of performance of this test methodwith service performance has not been determined.6.2 Apparatus:6.2.1 Scale,capable of weighing in increments of 0.1 lb(0.05 kg)or 1 oz(28 g).6.2.2 Tape Measure,capable of measuring in increments of116in.(1.6 mm).1This specification is under the jurisdiction of ASTM Committee C11 onGypsum and Related Building Materials and Systems and is the direct responsibilityof Subcommittee C11.02 on Specifications and Test Methods for Accessories andRelated Products.Current edition approved Nov.1,2014.Published November 2014.Originallyapproved in 1977.Last previous edition approved in 2014 as C847 14.DOI:10.1520/C0847-14A.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.*A Summary of Changes section appears at the end of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 6.3 Materials shall satisfy the following:6.3.1 Metal LathSpecification C847.6.4 SamplingOne sheet shall be selected from each bundleor package,but not more than five sheets from any oneshipment for testing.6.5 Specimen Preparation:6.5.1 Measure and record the width and length of eachspecimen.NOTE1For paper-backed lath,remove the paper and glue from thelath before weighing the specimen.6.5.2 Each specimen to be weighed shall be permitted to befolded.6.6 Procedure:6.6.1 Attach the scale to a suitable support and tare the scaleto zero.6.6.2 Attach the specimen to the scale.6.6.3 Record the weight of the specimen.6.6.4 Calculate the number of square yards of materialpresent in each specimen.NOTE2The number of square yards per specimen is determined bytaking the area of the specimen in square inches(square mm)and dividingthe area by 1296 in.2/yd2(995 389 mm2/m2).6.6.5 Calculate the weight per square yard for each speci-men.NOTE3The weight per square yard is determined by dividing theweight per specimen by the number of square yards of each specimen.6.7 Number of