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By:J.P. <br />Date:8/13/24 <br />Rooftop Solar Panels Wind Pressures (Section 29.4, ASCE 7-16) <br />Vult =100 mph Kzt =1.00 (sec 26.8.2)h =15 ft <br />Exposure Category =C Kz = 0.85 (sec 26.10.1) <br />Roof Zone =2 Kd =0.85 (sec 26.6) <br />Roof θ =7-27 deg Ke =1.00 (sec 26.9) <br />qh = 0.00256 Kz Kzt Kd Ke V2 qh =18.50 (eq. 26.10-1) <br />GPp =-2 uplift γE =1.5 (sec 29.4.4) <br />γa =0.78 (fig 29.4-8) <br />γE =1.5 FIG 29.4-7)γc =0.94 (fig 29.4-7)hpt =0 <br />γa =0.78 (fig 29.4-8)γp =0.9 (fig 29.4-7)ω =0.00 deg (panel tilt) <br />GPp =-2 uplift GCrm =1.4 uplift <br />p = qh (GPp) γE γa (eq 29.4-7)p = qh (GCrn) γE γC γp (eq 29.4-6) <br />p =-43.2 p.s.f.p =32.8 p.s.f. <br />Check Anchorage to Existing Structure <br />0.6DL - 0.6W controlling load combination (eq. 16-15 for ASD) <br />DL =2.9 p.s.f.dead load of panel (including rack system) <br />W = 43.2 p.s.f.wind load normal to face of panel <br />Arealag =11.3 sq. ft.area tributary to each anchor <br />SPanc =4.0 ft.spacing of anchors <br />Puplift = Arealag (0.6DL - 0.6W) =273.6 lbs.total uplift on anchor <br />Material =SP lumber anchor material <br />Dialag =5/16 in.diameter of screw <br />Penlag =2.5 in.min. penetration to existing framing <br />W lag =307 lb.withdrawal load per ICC ESR3223 <br />CD =1.6 load duration factor for wind per NDS Table 2.3.2 <br />Ct =0.8 temperature factor per NDS Table 2.3.3 <br />Noscrews =1 number of screws in withdrawal <br />Pallow = Wlag * Noscrews =982.4 lbs.total allowable withdrawal on anchor <br />Puplift <br />Pallow <br />Anchorage =USE (1) 5/16IN. DIA. LAG SCREW(S) AT 4FT. MAX. O.C. W/ 2.5IN. MIN. PENETRATION <br />Wind Uplift Anchorage <br />Flush Mounted Panels - ASCE Section <br />29.4.4 (where applicable) <br />Flat Roof Panels - ASCE Section 29.4.3 <br />(where applicable) <br />=0.28 < 1.00 Anchor is OK! <br />8/13/2024 10:54 AM <br />6 of 7 <br />©McPherson Engineering <br />2425 W Bobby Ln <br />10/21/2024