ASTM_C_1570_-_03_2016.pdf

Designation:C157003(Reapproved 2016)Standard Test Method forWind Resistance of Concrete and Clay Roof Tiles(AirPermeability Method)1This standard is issued under the fixed designation C1570;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.Scope1.1 The air permeability of tile roofing systems is a criticalfactor in determining the wind resistance of tile roofing asapplied to a roof.This Standard describes a procedure formeasuring the air permeability of clay and concrete tile andslate roof systems when applied to a small section of roof deckin accordance with the manufacturers instructions.1.2 This test procedure measures the air permeability of alaid array of unsealed clay or concrete roof tiles or slates.Thetiles or slates shall have a thickness between18-in.(3-mm)and2-in.(51-mm).1.3 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.1.4 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:2C43 Terminology of Structural Clay Products(Withdrawn2009)3C1167 Specification for Clay Roof TilesC1492 Specification for Concrete Roof Tile2.2 SBCCI Standard:SBCCI SSDT 11,SBCCI Test Standard for DeterminingWind Resistance of Concrete or Clay Roof TilesNOTE1This standard is based on the International Code CouncilsICC/SBCCI SSTD 11 and work derived from the tile industrys testingprograms completed in the Redland Wind Tunnel in the UK.2.3 ASCE Standard:ASCE 7,Minimum Design Loads for Buildings and OtherStructures43.Terminology3.1 DefinitionsFor definitions of terms used in this testmethod refer to Terminology C43,and Specifications C1167and C1492.4.Principle of the Test Method4.1 Air pressure is applied to the underside of an airpermeable assembly of a specified type of roofing elements.The difference in air pressure across the assembly and thevolume air flow rate are measured and used to determine the airpermeability of the assembly.5.Significance and Use5.1 The air permeability of roofing systems constructedfrom discrete elements,as is the case for clay and concrete tileand slate roof systems,is a critical factor in determining thewind resistance of the roof system.The ability of the roofsystem to relieve wind-induced uplift pressures as a result ofthe overall air permeability of the roof assembly relates to theresistance of the roof system to damage induced by wind.5.2 Natural wind conditions differ with respect to intensity,duration,and turbulence;these conditions are beyond themeans of this test method to simulate.6.Apparatus6.1 A plenum chamber is a rectangular box with a depth ofnot less than 1.64 ft(500 mm)or one-third of the least lateraldimension,whichever is the greater.The plenum chamber shallbe made airtight except for an open upper face to receive amounting board or cover panel,a tapping for a pressuredifference gage(relative to atmospheric pressure)and a con-nection to an air delivery pipe.The tapping shall be positioned1This test method is under the jurisdiction of ASTM Committee C15 onManufactured Masonry Units and is the direct responsibility of SubcommitteeC15.06 on Roofing Tile.Current edition approved Dec.1,2016.Published December 2016.Originallyapproved in 2003.Last previous edition approved in 2009 as C1570 03(2009).DOI:10.1520/C1570-03R16.2For 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.3The last approved version of this historical standard is referenced onwww.astm.org.4Available from American Society of Civil Engineers(ASCE),1801 AlexanderBell Dr.,Reston,VA 20191,http:/www.asce.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 to avoid direct alignment with the air delivery pipe.The shapeand area of the mounting surface shall be capable of acceptingthe number of test samples specified in 8.1 as a minimum.Aschematic of the air permeability apparatus is shown in Fig.1.6.2 An airtight removable cover panel shall be securedairtight to the plenum chamber.6.3 An open face mounting board to receive the roofingsubstrate and test samples.6.4 A controllable air flow generator shall be capable ofcontinuously delivering air at a rate such that the upliftoverturning moment on the roofing elements induced by