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Lag Screw Calculation (per ASCE 7-16) <br />Connection Demand <br />Spacing perpendicular to rail, in 34 <br />Roof Angle, degrees 20 <br />Roof Layout Gable <br />Wind Speed, mph 115 <br />z 0.95 <br />zt 1.00 <br />d 0.85 <br />e 1.00 <br />z 27.1 <br />Zones:1 2n, 2r, 2e 3r, 3e <br />Spacing parallel to rail, in 72 72 72 <br />p 2.00 2.67 3.19 <br />γE No No No <br />Effective Wind Area on each con., ft 17.0 17.0 17.0 <br />γa 0.71 0.71 0.71 <br />Uplift Force, psf 38.4 51.3 61.2 <br />Max. Uplift Force / Connection (0.6 WL), lbs 390.8 522.2 622.9 <br />Solar Dead Load (0.6 DL). Lbs 30.5 30.5 30.5 <br />Max. Uplift Force (0.6 WL - 0.6 DL), lbs 360.3 491.6 592.3 <br />Connection Capacity <br />Attachment FTG UNIRAC Flashloc Comp <br />Attachment location Framing <br />Fastener Type Lag Screw <br />Fastener Diameter, in 0.3125 <br />Embedment Length, in 2.5 <br />Lumber Species & Grade DFL #2 (Assumed) <br />Nominal Withdrawal Capacity W, lbs 665 <br /># of Screws 1 <br />d 1.6 <br />Screw Adj. Withdrawal Cap. W', lbs 1064 <br />Attachment FTG Strength with Cd, lbs 672 <br />Max applied load, lbs 592 <br />Max allowable load, lbs 672 <br />Compare Adjusted Withdrawal Capacity to ASD Factored Demand <br />Zones:1 2n, 2r, 2e 3r, 3e <br />O.K. O.K. O.K. <br />This calculation justifies the connection of the solar panels to existing roof members, by showing the connection <br />capacity is equal to or greater than the uplift force demands. <br />1410 N Parsons Pl <br />1/24/2025