b'climatic loads and how to incorporate them into the experi mental methodology. Initially, hourly temperature time series available for 564locations across Canada were analyzed for hourly fluctuations. The data available for these locations spanned 10 to 20 years, with the majority of the locations having 15 years of data available. A threshold value of 5C was chosen to identify the instances of hourly fluctuations above the threshold. The number of these cycles per year obtained from the time series were fit to a Poisson distribution (probability of exceed-ance is 2%), and the number of cycles for 50-year return periods was deter mined. For the analyses, the period from May to August was considered summer, during which a hot-weather shock would occur, and the period from December to March was winter, during which a cold-weather shock would occur. The above is summa rized in Fig. 28.The hot-and cold-weather shock values are Figure 22. Failure modes varied with curing time for an adhesive applied membraneinitially obtained based on air temperature. roofingsystem. The surface temperature that a roof compo nent will reflect under a specific air temperature will differ based on the component and its position within the system. That is why there is a need to establish the relation ship between the component temperature and the air temperature.Thereafter, the hot- and cold-weather shocks wall siding. Therefore, the factors that must be the component will be experiencing in arespected when determining the composition of scenario of 2C global warming magnitudethe cycles are: The cold and hot component weather shock can be determined. This framework can betemperaturesfollowed for all building envelope components The number of weather shock occurrencesand is not limited to roof components. As well,Q23: CAN A the param eters can be established for otherCLIMATE-DEPENDENT global warming magnitude ranges from 0.5CDURABILITY INDEX (CDDI) BE DEVELOPED FOR ROOFING to 3.5C. COMPONENTS?By taking asphalt shingles, for example, the CDDI can be explained as follows. Shingle Q22: CAN I APPLY WEATHERcomposition and behavior are complex, and SHOCK PARAMETERS FORattributing performance once installed as part Figure 25. Roofing system and vegetated system assembled together to form the vegetatedof a system to an individual property is difficult DURABILITY EVALUATION OFand inadequate. Developing a science-based Figure 23. Condensation below the roof membrane. roof assembly.ROOFING COMPONENTS? indicator that would combine key properties with the exposed climate severity of the material Materials are currently evaluated at labmay provide a more com prehensive indicator of temperatures. Materials age and deterioratethe materials long-term performance. The CDDI was developed to accomplish this. The CDDI differently when they experience weathercombines five critical prop erties: tear strength, shock cycles. Using the information from theoverlap strength, fastener pull-through, tensile strength, and granule loss.framework in Fig. 28 the hot- and cold-weatherFor each of these properties, the durability shock component temperatures and theirfactor and importance factor are calculated. respective number of occurrences are deter- The durability factor depends on the propertys reduction in strength after exposure to the mined. Also, to replicate the cycling that alreadyclimate zone-dependent weather shock protocol. naturally occurs with the change in seasons, theIf a prope rty is greatly reduced, that is an indication that the durability of the shingle is hot- and cold-weather shocks were alternated.low. The durability factor ranges from 0 to 3. A An important step for incorporating the weatherdurability factor of 0 is corresponds to reduction in strength greater than 45%, and durability shock framework into testing is the duration offactor of 3 is corresponds to reduction in strength the hot and cold cycles to ensure practicality ofless than 5%. A higher durability value indicates a more durable shingle. The impor tance factor the experiments. An example of how this canis assigned to each of the five critical properties be achieved is by setting a practical duration ofbased on the mode of field failures and indus-try consensus. The importance factor for each Figure 24. Air intrusion volume with and without the vapor barrier. the entire weather shock cycle and adjusting theproperty is greater than zero but less than 1, Figure 24. Air intrusion volume with and without the vapour barrier. as follows: tear = 0.2; overlap strength = 0.3; fastener pull-through = 0.2; tensile = 0.1; and 18IIBEC InterfaceJanuary 2025 granule loss = 0.2. By combining the durability Q18: What Are the TypicalClimate-RCI has been developedhourly temperature time series avail- factor and the impor tance factor for each of Components of an Asphaltby NRC. It takes into account pro- able for 564 locations across Canadathe critical properties, one can determine the Shingle Roofing (ASR)? jected changes in weather elementswereanalyzedforhourlyfluctua- classification level of CDDI, which can be either (wind,rainandtemperature)andtions.Thedataavailableforthesesilver (CDDI greater than 2 and less than 3) or Residentialroofsutilizedif- Figure 26. Wind aerodynamics and failure mechanisms of a vegetated roof assembly. gold (CDDI = 3).ferentmaterialcoveringssuchasprovidesthedesignloadsfor696locationsspanned10to20years,Figure 26. Wind aerodynamics and failure mechanisms of a vegetated roof assembly.metal,tileandshingles.Asphaltcities across Canada. The climaticwiththemajorityofthelocationsduration of each cycle. This must be achievedare 8 hot- and 6 cold-weather shock cycles. TheQ24: WHAT IS THE IMMEDIATE loadsareclassifiedintothreecli- having 15 years of data available. Awhile ensuring that the total number ofduration of 15 days, along with the breakdown ofNEED FOR COMMERCIAL shingles are used on almost 90 perThe hot- and cold-weather shockcomponentsandisnotlimitedtoROOFING?mate zone severity classes: normal,threshold value of 5C was chosenfluctuations for hot and cold weather shocks is8 hot and 6 cold cycles a day and the duration of centofCanadianresidentialroofsmaint ained. Ainitially obtained baseoofeach colcomponents.Aswell,thepa-Alterations to existing roofs (AER) have a major severe and extreme. This tool alsotoidentifytheinstancesofhourlyvalues are n example of a dark-colored rd onroofd and hot cycle, can be changed to bettercovering (asphalt shingle) is shown in Fig.29. reflect the building envelope material beingmarket share compared to new construction. becauseoftheiraffordability,easeformspartofCSAA123.26,Per- fluctuationsabovethethreshold.airtemperature.Thesurfacetem- rameters can be established for other The hot- and cold-weather shock cycle has aevaluated. An asphalt shingle will not absorbIn some regions of North America, AER market ofinstallationandadaptability.AThe number of these cycles per yearperature that a roof component willglobalwarmingmagnituderanges formance Requirements for Climatetotal duration of 15 days. Within each day thereand retain heat in a similar manner to a beigeshare is over 70%. AER includes, but is not residential roof is composed of fourResilience of Low Slope Membraneobtained from the time series werereflect under a specific air tempera- from 0.5C to 3.5C.major components: asphalt shingle,fit to a Poisson distribution (prob- turewilldifferbasedonthecom- IIBEC Interface19Roofing Systems. January 2025 underlayment, wood sheathing andability of exceedance is two per cent),ponent and its position within theQ22: Can I Apply Weather insulated attic (Fig. 27). In addition,Q21: Can Future Weatherand the number of cycles for 50-yearsystem. That is why there is a needShock Parameters for accessoriessuchasvents,sealant,Shocks Be Modelled forreturn periods was determined. Forto establish the relationship betweenDurability Evaluation of nails and eave protection also formthe analyses, the period from Maythe component temperature and the part of theASR. Roofing and Other Buildingto August was considered summer,air temperature. Roofing Components?Envelope Materials? duringwhichahot-weathershockThereafter,thehot-andcold- Materialsarecurrentlyevalu-Q19: Are There AnyBasedondiscussionswiththewould occur, and the period fromweather shocks the component willatedatlabtemperatures.Materi-Missing Links in theindustry,aframeworkwasdevel- DecembertoMarchwaswinter,be experiencing in a scenario of 2Calsageanddeterioratedifferently Current Code? oped using future climatic loads andduring which a cold-weather shockglobalwarmingmagnitudecanbewhen they experience weather shock howtoincorporatethemintothewould occur. The above is summa- determined. This framework can becycles. Using the information from Thecurrentcodedoesnotad- experimental methodology. Initially,rized in Fig. 28. followedforallbuildingenvelopethe framework in Fig. 28, the hot- dress the following:There is no guide for specifiers to have their design meet or ex-ceed the specified wind loads. Serving the roofing industry since 2005 withTherearenospecificclimateresponsive and dependable service and advice.requirementsformaterials.Serving Southwestern Ontario Since 1972The code only provides genericThe Fenn & Fenn Roofing Insurance Programloads that materials are expect-Commercialed to perform against.IndustrialGeneral Liability and Excess Liability Insurance including Hot WorksThere is no climate adaptation Maintenance SpecialistsBusiness Property Insuranceof future loads. Free Estimates / InspectionBuilders Risk, Contractors Equipment & Wrap Up Liability InsuranceThe code does not provide ma- 152 Thames Rd. W., Exeter, Ont. N0M 1S3 Automobile Fleet terial installation requirements. Tel: (519) 235-2802Fax: (519) 235-1532Email: speat@hay.netContractors Pollution Liability Insurance Q20: How to Classify the Easy Certificate of Insurance Programme saves timeFuture Climatic Conditions Be Contract Surety (Bonding) Quantified?Exceptional Service and contract risk and insurance adviceAs mentioned in Q1, there is a tool availablenamedClimate-RCIthatFenn & Fenn Construction Practice, a calculates the design load by account- Commercial and Residential Roofing division of HUB International Ontario Ltd.ingforfutureclimaticconditions.Trinity Roofing Ltd. specializes in a variety of roofing applications and Tel:(905) 836-6066It can be accessed at nrc.canada.ca/ waterproofing for residential, commercial and institutional buildings. Toll Free:(866) 269-8799en/research-development/productsPhone: 416-630-9213URL: www.trinitycanada.com675 Cochrane Dr., East Tower, Suite 200-services/software-applications/Fax: 416-630-1722 Email: info@trinitycanada.comMarkham, ONL3R 0B8climate-rci.ORN THE ONLY SOURCE FOR PROFESSIONAL ICI ROOFING CONTRACTORS IN ONTARIO ONTARIO ROOFING NEWSISSUE 1 202521'