b'~ Granule Adhesion1995 MRCA Study-ASTM D5147 Granule Embedment Continued from previous page AaJ!I" B~rC" ~ ule adhesion test on SBS productssenled in September 1997 at theC 1 used in the Midwest this year. The"Fourth International S D,,,"ll- - ~ ymposium- .,. I~ MRCAfeelsthatthispropertyon Roofing Technology." The titleE must be monitored, since no inde of the paper was"Durability ofF~~ "\'- i- - -in~pendent data source is availableTwo-Ply SBS Modified BitumenG~~ this highly-competitive segmentMembranes:Ten-Year Perfor H~8- i - - - - -of the roofing industry.mance Results." The paper was"-T results of the 1995, 1996authoredby Claude Duhechesne, and1998granuleembedmentTim Kersey and Michel Lelong.Granule Loss (gram) tests are shincharts. ItFor that study, five SBS roofs ownthe should be noted that extensive lowinstalledinthemid-1980sin temperaturewas alsoFlorida, Arizona, OhioWash 1996 MRCA Study -ASTM D5147 Granule Embedment flex testingand performed. The r tsbe pre ington wereed.gran A- - I esul willsampl Theule sented in are article.coveragereportedon thesein Bi futu_,_ In 1995,B, C, D,service roofs ranged from aofC=1 Manufacturerslow EIthe 2max 90 percent in one of theD- -+-andexceededgramFloridaEj~L imum granule loss. The 1996 testroofs to 98 percent on the SBS+- - : F~i Manufactur J~-program showed thatroof sampled in Ohio. There is no~f-ers B,DIe eeded thecorrelation between the granuleG~-.i-C,andstillxc2maximum granule loss onscrub test and the granule c H~1 It gramover ~I their SBS product we tested.age reported inp II theiraper. is068 In1998wesawa markedTh is the first time the MRCA improvement in granule adhesion;te res on SBS granule adhe Granule Loss (gram) stults this wasnot unexpectedsincesion havebeenpublished. The were however,1998 MRCA Study -ASTM D5 I 4 7 Granule Embedment users now had ASTM standards toresults,presented officially refer to. Manufacturers Cat the MRCA conventions in the A and Fthe 2maxi respectiveyearsshown inthe81 exceededgram mum on theirrated SBScharts.Atthesepresentations,82t"r non-FR sheets.ItappearsthattheFRm \'were listed.Cl+ anufacturers names sheets may be subject to a higherIn the fal I of 1999 at the"50thC2-quality controlTo confirmAnnualMRCA Convention andDtt.L r effort.Fl. (ordeny)thisobservation,theTrade Show"in Kansas City, Mo.,F2 G\' T&RCommitteeisconductingthe testresults,along with the- I-,ufacturers\'rl another test program this year.individual man names It should be notedthe sam w l be listed. thatil0467 ples are taken from one roll only.Ifyouhaveanyquestions,Granule Loss (gram) The roll is procured directly fromcomments or suggestions on this contractors or distribution ware MRCA test program, please call houses in the Midwest. Whilethe MRCA office. this is not aistica valid samplingRene M. Dupuis is an MRCA stat lly principrocedure, it does give the roofingTechnical Adviser. He is a contractor asnapshotpal and president of Structural continuous in time of the granule adhesionResearch, Inc. in Middleton, Wis. over the last half of this decade on SBS products used in the Midwest. A recentpaperongranule embedment of aged SBS modified bitumen roofs in service was pre-7'