ASTM_D_6777_-_16.pdf

Designation:D677716An American National StandardStandard Test Method forRelative Rigidity of Poly(Vinyl Chloride)(PVC)Siding1This standard is issued under the fixed designation D6777;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.1.Scope*1.1 This procedure describes a method to determine anumerical value indicating the relative rigidity or stiffness ofvinyl siding panels.This procedure is not intended for routinequality control inspection during the manufacture of vinylsiding.The rigidity of vinyl siding is believed to be controlledprimarily by its configuration and is not believed to besignificantly influenced by manufacturing variables.1.2 Vinyl siding with higher rigidity is often easier to handleand install than siding of lower rigidity.It is expected toprovide a straighter appearance when installed on walls havingan uneven surface.1.3 All other vinyl siding requirements and test methods canbe identified through Specification D3679.1.4 There is no known ISO equivalent to this standard.1.5 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D618 Practice for Conditioning Plastics for TestingD883 Terminology Relating to PlasticsD1600 Terminology forAbbreviated Terms Relating to Plas-ticsD3679 Specification for Rigid Poly(Vinyl Chloride)(PVC)SidingD5947 Test Methods for Physical Dimensions of SolidPlastics Specimens3.Terminology3.1 DefinitionsDefinitions are in accordance with Termi-nology D883 and D1600 unless otherwise indicated.3.2 Definitions of Terms Specific to This Standard:3.2.1 relative rigidity(of PVC siding)stiffness of a pieceof vinyl siding.3.2.2 rigidity index(of PVC siding)amount of sample sagor deflection relative to sample length.The“rigidity index”isdefined as 100 minus the deflection value,divided by thesample length,expressed as a percentage.4.Summary of Test Method4.1 In this procedure the test specimen is a piece of vinylsiding 100 in.long.This specimen is placed on top of a leveltable with 50 in.of the specimen extending unsupported pastthe edge of the table,allowing the specimen to sag under itsown weight.The amount of sag that occurs is used to calculatea rigidity index for the sample.5.Significance and Use5.1 Vinyl siding with higher rigidity is often easier to installthan siding with lower rigidity and expected to provide astraighter appearance when installed on walls having anuneven surface.5.2 The rigidity of vinyl siding is believed to be controlledprimarily its characteristic configuration and is not believed tobe significantly influenced by manufacturing variables.Sidingweight has little influence on this test.6.Interferences6.1 The supporting table and floor must be flat and level.Calibrations of flatness,parallelism,and levelness,as de-scribed in 9.2-9.4 shall be performed before running this test.7.Apparatus7.1 This procedure requires a table that is flat and level.Thetable must be at least 50 in.long and at least as wide as thewidest test specimen to be measured.The height of the table isnot critical.The edge of the table over which the specimen willextend shall not have a radius more than 0.125 in.The tablemust be positioned on a hard surface or floor(no carpet)that isalso flat and level over a length extending at least 50 in.fromthe edge of the table.1This test method is under the jurisdiction of ASTM Committee D20 on Plasticsand is the direct responsibility of Subcommittee D20.24 on Plastic BuildingProducts.Current edition approved May 1,2016.Published May 2016.Originallyapproved in 2002.Last previous edition approved in 2010 as D6777-02(2010)1.DOI:10.1520/D6777-16.2For 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 7.2 Aweight consisting of a 5 lb sand bag is used to hold theend of the siding specimen firmly against the table top.Theweight shall be as wide as the widest siding specimen to betested.7.3 A line shall be drawn on the table to ensuring that thespecimens are positioned perpendicular to the edge of the table.This line shall be drawn as a perpendicular to the edge using alarge framing square at least 10 in.on each side.7.4 A rigid ruler(such as a folding carpenters ruler or largemetal framing square)is u