b'Polyisocyanurate Insulationinsulations blown with hydrocar- eters,thevariationinresults bons and pentane, which are sus- among the different aged insula-ceptible to condensation at coldertions should be expected. The overall results indicate the in-service aging temperatures. But what is interest-ingisthatthoughthesesamplesCompressive Strengthhave been in service for 20 years, theyThecompressivestrengthof have not shown linear aging character- thepolyisocyanurateinsulationprocess did not lower the compressive strength istics like the other samples. specimenswastestedinaccor-Withrespecttotheinfluencedance with ASTM C1289, which of temperature, one of the missingrefers to a test method in ASTMbelow the current requirements, even after 13 to pieces of information in these field- D1621,StandardTestMethods obtained samples is the location offor Compressive Properties of Rigid theinsulationwithinthesystem.CellularPlastics.Todetermine For example, was it a one- or two- compressive strength, five 2- by20 years of aging in roof assemblies.layer insulation layout, and if it is a2-inchspecimenswereevalu-two-layer layout, was the insulationated. The specimens were placed samplethetoporbottomlayer?betweencompressionplates, Withalltheseinfluencingparam- andthecrossheadcompressed the specimen at a constant speedFlexuralPropertiesofBlock-Typethatwereundergoingretrofitor equal to 10 per cent of the speci- ThermalInsulation,Method1,replacement.Althoughconclu-men thickness per minute0.01Procedure B. If sufficient mate- sionscannotbedrawnregard-inchesperminute.Thetestwasrial was received, four specimensing the thermal drift of the aged conducteduntilthespecimenwere cut from the sample, twosamples and their relation to pre-had been compressed to about 13fromeachdirection.Whenin- dicted LTTR values, their thermal per cent of its original thickness,sufficient samples were received,as specified in the standard to de- onlytwospecimenswerecutperformances showed 50 per centtermine the load applied at 10 perfrom the same direction. Speci- of the collected samples measured an R-value of 5 per inch or more, cent deformation. menswerethreeinchesby12even after being exposed to field It is noted compressive strengthinches. During the test, the load and flexural strength testing waswas applied to the specimens atconditions for 13 or more years.completed on remaining materialaconstantrateof0.1inchperThe in-service aged polyisocy-after producing the R-value speci- minute per one inch of thickness. anurateinsulationsamplesalso - PMI Programs- Modified Bitumen- Built Up Systemsmens.Therefore,basedontheAllsamplessurpassedthewere tested for mechanical prop Metal Roof Systems- Waterproofing- Restoration quantityofinsulationreceived,minimum requirement for break- erties by evaluating the compres Emergency Services- Roof Anchors- Single Ply - Roof Top Decks- Sheet Metal- Invertedcompressivestrengthandflex- ing load of the current standardsiveandflexuralstrengths.All ural strength evaluations were notof 17 pound-force for all typessamplestested,withtheexcep-possible on all samples. andclasses,excludingTypeI,tion of one, surpassed the current The averages of the individualwhich is faced with both majorminimumrequirementforcom-specimenswerecomparedwithsurfacesofthecorefoam,andpressivestrength.Similarly,allASTM C1289 to verify the mini- TypeII,Class4.Thebreakingbut two samples met the current mumrequirementforthecom- loads were then used to calculateflexural requirement, maintaining pressivestrengthoffacedrigidthe flexural strengths, which weresufficient flexural properties. The cellular polyisocyanurate thermalnormalizedforthespecimenstudy revealed that though there insulation boards. thicknesses. are changes that occur within poly-TheminimumrequirementMostofthesamplestested, is16poundspersquareinchwith the exception of Sample #6,isocyanurate insulation as a function NOW formostboardtypes,excludingmet the current requirement of aof age, a majority of the samples re-A NEW ROOFING higher grades and Type II, Classminimum flexural strength of 40tained reasonable performance.AVAILABLEIN BULK FROMASPHALT WITH AFutureinvestigationsthat LOWER EVT WHICH4, which is a high-density polyiso- psi for all polyisocyanurate types, REDUCES FUMES cyanurate board faced with coatedexcept Type II, Class 4. The old- wouldprovideessentialinfor-By BITUMAR AND ODOUR. oruncoatedfiberglassmatfac- estspecimentestedforflexuralmationincludequantifyingthe ers on both major surfaces of thestrength was specimen 4, whicheffectsofmoistureonaging 11155 St-Catherine Street EastMontreal-East, QCH1B 0A4 core foam and used at a maximumwas aged for 20 years in-servicepolyisocyanurateinsulation,a Tel. : 514 645-4561 thickness ofan inch. All boardsandsurpassedtheexistingflex- composition analysis to quantify bitumar.com tested, with the exception of Sam- ural requirements. These resultsthe rate of blowing agent diffusion 40 % ple#6,surpassedtheminimumsuggestthatevenafter13toand an investigation of the effect ZEROODOUR requirement.Theoverallresults20yearsofagingnaturallyin-35 % oftemperatureshocksontheWhen cold 30 % indicate the in-service aging pro- service,theflexuralstrengthof% of fumes in the air 75 % ReductionUp to 177C long-term thermal performance of25 % cess did not lower the compressivepolyisocyanuratesurpassedthe75 % less fumes than 20 % polyisocyanurate insulation.strength below the current require- currentrequirementsformost regular roofing asphalt 15 % SudhakarMolletiisaseniorBURPAK ZERO contains an10 % ments, even after 13 to 20 years ofsamples,maintainingsufficient odour suppressant which 5 % Regular BUR aging in roof assemblies. flexural properties. researchofficerattheNational combined with a lower0 % ZERO Research Council of Canada; Bas temperature of installation,93 121 149 176 204 232* 260 288** 316Cminimizes asphalt odour Temperature Flexural Strength Analysis Baskaran is a group leader at NRC; Zero complaint on odour * Theidealviscositytemperatureistypicallylowerby23Cfor TheflexuralstrengthoftheWeanalyzedtheR-valueofand Dominique Lefebvre is a for- BURPAKZEROwhencomparedwithregularroofingasphalt. samples was tested in accordancein-service aged polyisocyanurateComplaints are timeTherefore,thereisnoneedforthekettletemperature mer research officer at NRC.consuming and reducetoexceed232CwhenusingBURPAKZERO.productivity on job sites **MaximumtemperatureofakettleasperASTMD312. withASTMC203,Standard TestinsulationsamplesrecoveredReprintedwithpermissionfrom MethodsforBreakingLoadandfrom low-slope membrane roofsProfessional Roofing magazine.14ONTARIO ROOFING NEWSISSUE 1 2020 THE ONLY SOURCE FOR PROFESSIONAL ICI ROOFING CONTRACTORS IN ONTARIO ORN'