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STRUCTURAL ANALYSIS FOR NEW PHOTOVOLTAIC SOLAR SYSTEM <br />NOTE: <br />THESE CALCULATIONS ARE BASED ON INFORMATION AND MEASUREMENTS PROVIDED BY THE CONTRACTOR FROM <br />HIS SITE INSPECTION. <br />1 Project Information:PV SOLAR ARRAY: KNUTH RESIDENCE <br />Latitude 33.7540° deg N 1006 N. LOWELL STREET, SANTA ANA, CA 92703 <br />Longitude -117.879° deg W <br />Wind Speed 110 mph 95 mph (ASCE 7-16) <br />Wind Exposure C <br />Site Class D <br />Seismic Design Category D <br />2 Loads: <br />Existing Roof Dead Loads: <br />2 x 4 Rafters @ 24" OC 0.7 psf <br />1/2" Roof Sheathing 1.7 psf <br />Roof Felt 1.5 psf <br />Composition 5.0 psf <br />Miscellaneous 3.1 psf <br />Total 12.0 psf <br />Existing Snow Load:0.0 psf <br />Existing Roof Live Load:20.0 psf <br />Proposed Roof Live Load:20.0 psf <br />Wind Load: Using CBC 2019 (ASCE 7-16), Chapter 29: Wind Loads on Rooftop Equipment, the <br />following wind pressures were calculated. <br />p = qh (GCp) (ge) (ga) = 8.58 -44.13 psf <br />qh = 0.00256 Kz Kzt Kd Ke V2 = 21.76 psf <br />Kz = 0.85 (0-15 = 0.85, 20 = 0.90, 25 = 0.94, 30 = 0.98, 40 = 1.04) <br />GCp = 0.7 -3.6 (Roof pitch = 18 deg, Zone = 2, Aeff = 21.3 sf) <br />ge = 1.50 <br />ga = 0.80 <br />Lag Bolt Capacity: <br />5/16" lag bolt capacity = 270 lbs per inch embedment <br />With 2 1/2" minimum embedment, capacity = 675 lbs <br />Required Capacity: <br />44.13 psf * 13 modules * 21.3 sf = 12220.4 lbs <br />12220.4 lbs / 20 lag bolt connections = 611.0 lbs <br />The pull-out capacity of the 5/16" lag bolts with a minimum 2 1/2" embedment into the roof rafter is sufficient <br />to meet the demand of the wind uplift force on the solar system. <br />Seismic Load: Per the CEBC 2019 Section 503.4, if the demand-capacity ratio of the lateral load-carrying <br />elements increases less than 10% due to the addition of the solar system, no special provisions or structural <br />modifications are required. <br />Existing Roof Weight = 12.0 psf * 3160 sf = 37920 lbs <br />Weight of Solar System = 13 modules * 47.7 lbs + 138 lbs of racking = 759 lbs <br />759 lbs / 37920 lbs = 0.02 <br />The increase in load from the solar system will not increase the demand-capacity ratio of the existing lateral <br />load-carrying elements by over 10%. <br />NOTICE:VISION CIVIL ENGINEERING: JENNIFER KEMME, PE <br />ANY CHANGES TO OR USES OF THESE DOCUMENTS 12273 11TH STREET, YUCAIPA, CA 92399 <br />WITHOUT THE WRITTEN CONSENT OF VISION 909.754.8300, JENKEMME@VISIONCE.COM <br />CIVIL ENGINEERING IS STRICTLY PROHIBITED.RCE 73054, EXP 12/31/22 <br />Prepared by JENNIFER KEMME 7/3/2022 Page 1 <br />1006 N Lowell <br />Street08/11/22