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Structural Calculations -Roof Mounted Solar System - 2 arrays April 22,2014 <br />Job: Luis Reyes Contractor: Sunpro Solar (Bob Kornmann) <br />· 2031 South Artesia 34859 Frederick St. Suite 101 <br />Santa Ana, Ca. 92704 * (714) 915-8744 Wildomar, Ca. 92595 * (951) 813-5408 <br />Description: (12) solar panels (217 total sq fO mounted in (2)arrays on (5) lines, 79 total feet of Sun <br />Frame rails supported by (23) standojfs connected to roof with (1) lag screw each through roof <br />diaphragm (sealed) and supported by 2x4 trusses, 24" c/c on south & eastfacing roofs of existing <br />1-story residence with standardjlush mount on 3:12 pitch comp roof at job address shown above.Area <br />at bases to be patched with new roofsealant per Professional Solar Products installation instructions. <br />Page 3 <br />Solar System Vertical Loads per support:from page 2 <br />DL =26 lb/support (395 lb/15 supports) (LL = 0, no walking on solar panels) <br />Wind = 118 lb/support * <br />TL = 144 max lb/support down load <br />* 7.02 psfx 16.81 d (ASCE 7-10 figure 6.3, for uplift - see below) <br />Vertical Loads per sq ft:DL = 395 lb/141 sq ft projected =2.80 psf <br />LL =0.00 psf <br />Wind (see also uplift) <7.28 psf <br />TL =10.08 psf <br />Vertical Wind Pressure (Uplift):Consider Worst Cases: 14.04 defrees, cases E, F,G&H <br />Solar System Total Net Vertical Load per support: Total plan area 141 sq ft (vertical projected) <br />Vertical Pressures - Uplifts: a = 3', Zones per Figure 6-3, ASCE 7-10: <br />Zone E: at windward edges (approx 78 sq ft plan view) eff. wind area = 6.8 sq ft uplift = - 20.7 psf <br />Zone F: leeward edges (approx 78 sq ft plan view) eff. wind area = 6.8 sq ft uplift = - 20.7 psf <br />Zone G: center of roof windward area (63 sq ft plan view) ewa = 16.81 sq ft uplift = - 11.7 psf <br />Zone H: center of roof leeward area (63 sq ft plan view) ewa = 16.81 sq ft uplift = - 11.7 psf <br />so total uplift for zones E+Gor F+H (whichever is greater): <br />Total wind pressure = -(16151b + 737 lb) * Total uplift = 2352 1b (worst case wind direction) <br />Max Net uplift (wind uplift- dead load) = 2352 lb-395 1b = 1957 lb@standoff connections <br />Ave net uplift per connection (15 connections) = 130 1b per connection <br />Worst single uplift per connection = 207 lb (10.02 sqft effective wind area x 20.7 psf@ array 2) <br />232 lb/inch of embedded threadfor %" lags * 274 lb/inch of embedded threadfor 5/16" lags <br />313 lb/inchofembedded threadfor 3/8" tags, Minimum threadlengthinto truss chord 2 92" : <br />R = 580# per lag for %" lags, R = 685# per lag for 5/16" tags, R = 783# per lag for 3/8" tags: <br />With min. 1 lag per support, Max uplift per lag = 2071b < 685 min. -OK <br />So, uplifts due to 110 mph ultimate winds are easily res!sd-by-the,co designed in thisproject. Lateral forces due to seismic or 110 mph ultinate windNre,aiso resisigd adequately bythe connections as shown in the herein design.(s¢21Gge 21. <br />,nTreettons <br />A 091\AA <br />/30/161 5Lawrence R. Phelps, Callf Lic. Renewal 9, <br />31130 Avenida Det-Reposo, Temecula, California 92591 <br />Cell/voice (951) 297-0555 - O#ice/voice (951) 694-6336