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Lag Screw Calculation (per ASCE 7-16) (Roof 1) <br />Connection Demand <br />Spacing perpendicular to rail, in 40 <br />Roof Angle, degrees 20 <br />Roof Layout Gable <br />Wind Speed, mph 115 <br />Exposure Coefficient, Kz 0.85 (Table 26.10-1) <br />Topographic Factor, Kzt 1.00 (Table 26.8.1) <br />Directionality Factor, Kd 0.85 (Table 26.6-1) <br />Elevation Factor, Ke 1.00 (Table 26.9-1) <br />Velocity Pressure qz, psf 24.3 (Table26.10-1) <br />Zones:1 2n, 2r, 2e 3r, 3e <br />Spacing parallel to rail, in 72 72 72 <br />GCp (max)(Figure 29.4-7)2.00 2.58 3.07 <br />Exposed Panels? (γE = 1.5) (Fig. 29.4-7)No No No <br />Effective Wind Area on each con., ft 19.8 19.8 19.8 <br />Pressure Equalization Factor, γa (Figure 29.4-8)0.68 0.68 0.68 <br />Uplift Force, psf (Equation 29.4-7)33.2 42.7 50.9 <br />Max. Uplift Force / Connection (0.6 WL), lbs 393.6 507.0 603.6 <br />Solar Dead Load (0.6 DL). Lbs 35.6 35.6 35.6 <br />Max. Uplift Force (0.6 WL - 0.6 DL), lbs 358.0 471.5 568.0 <br />Connection Capacity <br />Attachment FTG Everest K2 Flat Tile Hook <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 2 <br />Load Duration Factor Cd 1.6 <br />Screw Adj. Withdrawal Cap. W', lbs 2128 <br />Attachment FTG Strength with Cd, lbs 658 <br />Max applied load, lbs 568 <br />Max allowable load, lbs 658 <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 <br />connection capacity is equal to or greater than the uplift force demands. <br />1012 N King St <br />1/23/2025