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TOWNSEND RAITT II <br />ROOFTOP PV <br />Project No. 21-001 <br />5/19/25 <br />Check Building for PV <br />Roof Loads weight (psf) Wall Loads weight (psf) <br />Roofing 4.4 Stucco 10 <br />15/32" Sheathing 1.5 15/32" sheathing 1.5 <br />Roof Trusses 3 2x6 @ 16"oc 1.5 <br />Insulation 1.0 Gypboard 1.8 <br />Fire Sprinklers 1.0 Misc 1.2 <br />Girders 1.5 Wall Total Weight 16 psf <br />Ceiling 1.8 <br />Mechanical 1.5 <br />Misc.1.3 <br />Total 17.0 psf <br />PV Weight 3.0 psf <br />System Total 20.0 <br />Check existing structure per California Existing Building Code Section 503.3 and 503.4 <br />Vertical Capacity (CEBC 503.3) <br />Lateral Capacity (CEBC 503.4) <br />Building Areas <br />Building #1 <br />Roof Area 3736 ft2 <br />Wall Area 500 ft2 <br />PV Area 1183 ft2 <br />Wind Check <br />The modules are mounted parallel to the roof, therefore the wind loading will not change. <br />Seismic Check <br />Existing 71512 lbs <br />Solar Weight 3549 lbs <br />New Total Weight 75061 lbs <br />Percentage Change 5.0% <br />Total increase in weight to the structure is less than 10%, therefore the existing structure is ok <br />Modules may not be walked on after installation. The live load on the roof is replaced with the dead load of <br />the PV system. This is less than the live load, therefore the vertical system is ok to support the system. <br />Photos of the existing roof were reviewed to look for signs of potential distress in the roof or poor drainage <br />which increasing the load on the roof would make worse. The photos showed that the roof appeared to be <br />in good condition without signs of damage or significant ponding. Based on this observation as well as the <br />live load offset, the roof is sufficient to support the proposed PV system. <br />6 of 9