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Page 2 of 2 <br /> D. Solar Panel Anchorage <br /> 1. The solar panels shall be mounted in accordance with the most recent Sunmodo installation <br /> manual. If during solar panel installation, the roof framing members appear unstable or deflect non- <br /> uniformly, our office should be notified before proceeding with the installation. <br /> 2. The maximum allowable withdrawal force for a #14 wood screw in 1/2" plywood/OSB board is 55 <br /> lbs per screw(per APA technical note E830d). Considering the variable factors for the existing roof <br /> framing and installation tolerances, we require that a minimum (2)screw be attached to the existing <br /> rafter/truss minimum 2" penetration (378 lbs)with the balance of the screws (3) connected into the <br /> existing decking (3 x 55 = 165 lbs) Total uplift = 543 lbs). Based on this, the connections will be <br /> adequate and will include a sufficient factor of safety. <br /> 3. Considering the wind speed, roof slopes, size and spacing of rafters, and condition of the roof, the <br /> panel supports shall be placed no greater than 48" on centers. <br /> 4. Panel supports connections shall be staggered to distribute load to adjacent rafters. <br /> Based on the above evaluation, this office certifies that with the racking and mounting specified, the existing <br /> roof system will adequately support the additional loading imposed by the solar system. This evaluation is in <br /> conformance with the 2018 Washington State Residential Code, current industry standards, and is based on <br /> information supplied to us at the time of this report. <br /> Should you have any questions regarding the above or if you require further information do not hesitate to <br /> contact me. <br /> V <br /> truly yours, <br /> Scott E.Wyssli PE <br /> Washington License 111163 <br /> GOA s l <br /> 201111634Q <br /> �It �CISTER�� <br /> ss�O N A 1, ENG` <br /> Signed 1/04/2023 <br /> CONSULTING <br />