b'TECHNOLOGYA collaborative approach Une approche collaborativeDespite possible variations and optional components inMalgrlesvariationspossibles,ilestparfoisimpossiblede test reports, sometimes it is impossible to find a roofingtrouver un assemblage de couverture qui rpond aux charges assembly that meets the calculated wind loads. All partiesde vent calcules. Toutes les parties doivent travailler ensemble must then work together to find the best solution. Itpourtrouverlameilleuresolution.Ilpeuttreconseillde may be advisable to change the category of the roofingchanger la catgorie dassemblage de couverture (dun assem-assembly (from a mechanically attached to an adheredblage fix mcaniquementun assemblage coll, par exemple). assembly, for example), if an assembly of that categoryPar ailleurs, un assemblage mislessai conformmentla meetstherequestedloads.Alternatively,anassemblynorme CSA A123.21, mais dont la rsistance est insuffisante, testedasperCSAA123.21butshowinginsufficientpeut quand mme tre envisag si des changements peuvent resistance may still be considered if changes can be madetreapportspourenamliorerlarobustesse.Lesrapports to improve its robustness. Uplift resistance test reportsdessai de rsistance au soulvement, combinsdes donnes coupledwithadditionalevidenceandperformanceprobantes etdes mesures de rendement supplmentaires (des metrics(smallscaletestingcouldberequired)mightessaispetite chelle pourraient tre ncessaires) pourraient allowthetestinglabtoperformathoroughreview.permettre au laboratoire dessai deffectuer un examen appro-Aconclusiveengineeringevaluationcouldbewrittenfondi. On pourrait rdiger une valuation technique concluante which would allow that upgraded assembly to be used.quipermettraitdutilisercetassemblageamlior.Toutefois, This evaluation will, however, be project-specific and willcette valuation sera propre au projet et ne sera valable que pour only be valid for the building under consideration.limmeubleltude. Through this process, liability is transferred from theGrceceprocessus,laresponsabilitesttransfredu designer to the engineer who authored the evaluation.concepteurlingnieur qui a rdig lvaluation. Par cons-Consequently, such engineering evaluations will only bequent, de telles valuations techniques ne seront mises que issued when sufficient supporting evidence is provided.lorsque seront fournies des preuves concluantes. What role do you play? Reality is often very differentQuel rle jouez-vous ? La ralit est souvent trs diffrente from the above description of the process. Designers mayde la description ci-dessus. Les concepteurs peuvent prescrire un indicate a specific roofing assembly in the specificationensemble de couverture spcifique et refuser dautres options. andrefusealternateoptions.ContractorsmayactasLes entrepreneurs peuvent agirtitre de concepteurs dans les cas the designer of record in cases where they are contactedo ils sont contacts directement par le propritaire de limmeuble. directlybythebuildingowner(yes,thewindload(Oui, le calcul des charges oliennes sapplique galement au calculations applies to re-roof as well!). It is not prohibitedremplacement de la toiture !) Il nest pas interdit aux entrepre-for contractors to take on this task. But if they do, theyneurs dassumer cette tche. Mais sils le font, ils acceptent la accept the liability that comes in the process and shouldresponsabilit.Ilsdevraientdoncenvisagerlembauchedun evaluate the option to hire a qualified design professional. concepteur qualifi.We have witnessed attempts by designers to transferNous avons t tmoins des tentatives des concepteurs de theirresponsibilitytocontractorsormanufacturers,transfrerleurresponsabilitauxentrepreneursouauxfabri-asking them to determine wind loads on buildings (orcants, en leur demandant de dterminer les charges oliennes to confirm their own calculations) as part of the biddingsur les btiments (ou de confirmer leurs propres calculs) dans process. This is a line that should not be crossed withoutle cadre de leur appel doffres. Cest une ligne qui ne doit pas full understanding that accepting this task makes youtre franchie sans comprendre pleinement que lacceptation de become,inwholeorinpart,thedesignerofrecord.cette tche fait de vous le concepteur, en tout ou en partie. La More often than not, few people outside of the designerplupart du temps, peu de personneslextrieur du concepteur have access to the information required to perform theont accs aux informations ncessaires pour effectuer le calcul calculation of wind loads, such as the surroundings of thedes charges olienn est, comme lenvironnement du btiment building or its openings. CRCA published an advisoryou ses ouvertures. LACEC a publi en juin 2018 un avis intitul bulletin in June 2018 entitled Roofing Contractors andResponsabilit des entrepreneurs en couverture et des concep-DesignersResponsibilitywhichprovidesadditionalteurs qui fournit des conseils supplmentaires aux entrepreneurs guidance to contractors in this scenario. dans ce scnario.The last four years have been filled with opportunitiesLes quatre dernires annes ont t remplies doccasions de to learn, challenge and tweak the process by which thepeaufiner le processus de slection dune toiture conforme au selection of a code compliant roofing assembly is made.Code. Notre industrie va certainement en apprendre davantage Our industry will certainly learn more and get better atetsamliorer,maintenantquelesautoritscommencent it, now that jurisdictions start to adopt the model codeadopter les lignes directrices du code modle. Nous esprons guidelines. The process will hopefully become seamless,que le processus se droulera sans heurt, jusqu ce que des until such time that changes are made to it. changements y soient apports. 46 ROOFING CANADA FALL/WINTER 2019'