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76 North Meadowbrook Drive <br />Scott E. Wyssling, PE Alpine, UT 84004 <br />Jon P. Ward, SE, PE office (201) 874-3483 <br />Gregory T. Elvestad, PE swyssling@wysslingconsulting.com <br /> August 22, 2022 <br />Green World Renewable Energy <br />4408 Ritchie Highway <br />Baltimore, MD 21225 <br />Re: Engineering Services <br />Guillen Residence <br />1508 East Washington Avenue, Santa Ana, CA <br />6.370 kW System <br />To Whom It May Concern: <br />We have received information regarding solar panel installation on the roof of the above referenced <br />structure. Our evaluation of the structure is to verify the existing capacity of the roof system and its ability <br />to support the additional loads imposed by the proposed solar system. <br />A. Site Assessment Information <br />1. Site visit documentation identifying attic information including size and spacing of framing <br />for the existing roof structure. <br />2. Design drawings of the proposed system including a site plan, roof plan and connection <br />details for the solar panels. This information will be utilized for approval and construction <br />of the proposed system. <br />B. Description of Structure: <br />Roof Framing: Assumed prefabricated wood trusses at 24” on center. All truss m embers <br />are constructed of 2x4 dimensional lumber. <br />Roof Material: Composite Asphalt Shingles <br />Roof Slopes: 20 degrees <br />Attic Access: Inaccessible <br />Foundation: Permanent <br />C. Loading Criteria Used <br /> <br />x Dead Load <br />o Existing Roofing and framing = 7 psf <br />o New Solar Panels and Racking = 3 psf <br />o TOTAL = 10 PSF <br />x Live Load = 20 psf (reducible) – 0 psf at locations of solar panels <br />x Ground Snow Load = 0 psf <br />x Wind Load based on ASCE 7-16 <br />o Ultimate Wind Speed = 95 mph (based on Risk Category II) <br />o Exposure Category C <br />Analysis performed of the existing roof structure utilizing the above loading criteria is in accordance <br />with the 2019 California Residential Code, including provisions allowing existing structures to not <br />require strengthening if the new loads do not exceed existing design loads by 105% for gravity <br />elements and 110% for seismic elements. This analysis indicates that the existing framing will <br />support the additional panel loading without damage, if installed correctly. <br />1508 E Washington <br />Ave - 2017830312/30/22