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EGiNE�ER� <br /> Ultra Rail Racking System with UR-60 Rail: <br /> The SnapNrack Ultra Rail Racking System is intended for the rooftop installation of solar photovoltaic modules and is <br /> constructed from an assortment of modular parts as described in this report and shown in the attached details. <br /> 1.500° <br /> Y <br /> 0.750' 0.750" <br /> UR-60 Rail <br /> Material: 600545Aluminum Extrusion <br /> i Area of Cross-Section,A. '0.515 Ire <br /> Moment of lnertla,-6: .0.327 in° <br /> H <br /> Moment of Inertia,6: 0.181 In° <br /> Centrold;Y(Bottom): 1.039 in <br /> N _ <br /> �+ X. _ —x Centrold,X(Left): 0.750 in <br /> Section Modulus,Sip: 0.270 In' <br /> c Section Modulus,Sb,n,m: 0.3151n3 <br /> Section Modulus,S.1d.: 0.242 Ina <br /> Y- <br /> Figure 1: Diagram of UR-60 Rail Profile Covered by This Report(with Section Properties) <br /> Flush-Mount System Geometry Limitations: <br /> Flush-Mounted PV modules are designed per the Components and Cladding provisions of ASCE 7. Flush-Mounted PV <br /> modules shall be oriented parallel to the plane of the�roof surface,and shall be located between 2"to 10"clear from the <br /> surface of the roof to the PV module. The maximum cantilever length of the rail is L/3,where "L" is the maximum rail <br /> span after adjustments, provided there is at least 1 module length between maximum cantilevers. The modules shall be <br /> centered between the rails with consideration of industry standard tolerance. The%"gap between each PV module has <br /> been considered in the span charts, and shall not be obstructed. Installations utilizing the Tile Replacement or Tile Hook <br /> attachment devices are permitted to have panels offset from the centerline of the rails. <br /> Attachment to Roof: <br /> The attached span tables include consideration of the attachment device capacity, based on UL 2703 load testing <br /> performed by SnapNrack. Tested load values are developed with 5/16" 0 lag screws with an effective embedment of 27 <br /> 1/2" into a Douglas Fir substrate,with a reference withdrawal (uplift or pullout) load capacity of 532 lb, and a reference . <br /> shear(side or lateral) load capacity of 270 lb for resisting short=term wind or seismic loads. Reference values are the <br /> base values, before any adjustment is made per the LADS. Installations into alternate substrates or which use alternate <br /> fasteners shall be permitted; provided that the fastener has tested or code-derived allowable load capacities,and meets <br /> one of the following two.criteria:A)The allowable load values for the alternate fastener shall meet or exceed the <br /> allowable values noted above for the 5/16"0 lag screws in Douglas Fir; or B)the span length identified in the"span <br /> tables"shall be reduced according to the more restrictive of the following two formulas: <br /> Alternate Reference Withdrawl Capacity <br /> Rail Span = Table Span <br /> 532 lb <br /> Or <br /> Alternate Reference Shear Capacity <br /> Rail Span = Table Span* - <br /> 270 lb <br /> These formulas shall not be used to increase the allowable span beyond the spans listed in the span tables. <br /> 1478 Stone'Point Drive,Suite 190, Roseville,CA 95661 <br /> T .916.961.3960 F 916.961.3965 w wwvv:pzse.com 3/923 <br /> Experience I Integrity I 'Empowerment <br />