b'In this era of net-zero buildings and climate resiliency, every detail toFigure 1: Visual impact of thermal bridging of roofing fasteners (courtesy: RCABC).the extent possible towardsProtective Roofing enhancing the energySafety Productsefficiency of the builtBYenvironment should be accounted and acknowledged at the design stage. The PR 100 Guardrail Systemis an efficient and practical perimeter guardrail that allows youeach area of the roof. For assemblies where performance-basedto work right to the edge of the roof.deck securement is not specified, fasteners can be added pre-Meets and exceeds OSHA & WCB requirementsscriptively by doubling the density of the fasteners along the Accommodates: parapets and cant stripsEasy to installperimeter and by at least 2.5 times the density at the corners. Provides unobstructed access to roof edgeThe roofing manufacturers also specify their own performance-based fastener densities. Based on the current industry practice, the fastener densities in both the MARS and PARS can range from 1.6 to 10.8 fasteners/m 2(0.15 to 1 fasteners/ft 2 ); see Figures 1 and 2. The effects of these fastener densities are not currently acknowledged in the thermal design of roof assemblies. Thermal bridging occurs in roof assemblies in which the uni-form thermal resistance of the assembly is interrupted by full or partial penetration of highly thermal-conductive materials, creating pathways for direct heat loss. Two types of thermalThe PR 600 Mobile Fall Protection Systembridging are linear bridging, which occurs at junctions between elements such as a parapet-roof-wall junction or at rooftop pen- can be moved along the roof by pulling the cart to the desired working location, etrations such as curbs and skylights, and point bridging, whichproviding a safe working area. The PR 600 meets O.S.H.A. compliance 1926.502D.is a localized bridging that occurs at points within the roof as-sembly caused by roofing fasteners or rooftop photovoltaics. Roofing & Sheet Metal Super Service CentresEnergy codes and standards have mainly focused on the insu-lation requirements in roof thermal design, omitting the impactEDMONTON, AB CALGARY, AB WINNIPEG, MB WESTON, ONof thermal bridging on energy loss. One reason for the omission(780) 432-2786 (403) 255-8236 (204) 338-7613 (Weston Road)could be the absence of codifiable data that could determine theBARRIE, ON HAMILTON, ON TORONTO, ON (416) 745-4111impact of thermal bridging on the thermal performance of the(705) 792-6683 (905) 560-2858 (416) 534-8421 WESTON, ONroofing assembly. In this era of net-zero buildings and climate re- OAKVILLE, ON PICKERING, ON LONDON, ON (Signet Drive)siliency, every detail to the extent possible towards enhancing the(905) 825-0034 (905) 426-4443 (519) 668-3626 (416) 744-2050energy efficiency of the built environment should be accounted and acknowledged at the design stage.www.sparmarathon.caORN THE ONLY SOURCE FOR PROFESSIONAL ICI ROOFING CONTRACTORS IN ONTARIO ONTARIO ROOFING NEWSISSUE 1 202021'