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SOLGEN <br />P O W E R <br />November 08, 2022 <br />Subject: Proposed Solar Panel Installation <br />Robert Trichler Residence, 1914 306th St SW, Everett, WA <br />To Whom it May Concern, <br />Our engineering department has reviewed information, gathered by our field crews, related to the proposed solar <br />panel installation at the above -referenced address. The purpose of our review was to determine the structural <br />adequacy of the existing roof. Based on our review and analysis of the available information, and in accordance <br />with governing building codes, it is our professional opinion that the existing structure is permitted to remain <br />unaltered for the proposed solar installation. <br />Governing Building Code: 2018 Washington Building Code (2018I BC) <br />Risk Category: II <br />Design Wind Speed: 110 mph (per ASCE 2-16) <br />Ground Snow Load: 15 psf <br />Roof Information <br />Roof Structure: 2x4 Manufactured Trusses @ 24" O.C. <br />Roofing Material: Asphalt Shingles )1 layer) <br />Roof Slope: 18 degrees <br />Roof Connection Details <br />RT Minis into 2x rafters or truss top chords at 48" O.C., install per design drawings and manufacturer spec <br />Locations per design drawings <br />Note: Required embedment length excludes tax topered tip of the screw, and embedment Into smothing. <br />Analysis <br />The proposed installation complies with the requirements of WAC Section 51-51-03240 R324A (Exception) and is <br />therefore deemed adequate to support the load of the rooftop solar system. <br />Specifically: 1) the system is designed for the local wind speed; 2) the ground snow load does not exceed TO psf; 3) <br />the total dead load of all items is less than 4 psf (actual value is approximately2.65 pSft; 4) Modules are not <br />mounted more than 18" off the roof; and 5) Supports are installed such that the dead load is spread across roof - <br />framing members and does not exceed 50lbs at any point. <br />Wind uplift on the panels has been calculated in accordance with the relevant provisions of ASCE 7-16. This loading <br />has been used to verify the adequacy of the connection specified above. Connection locations should be in <br />accordance with design drawings. <br />Conclusion <br />