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Page 2 of 2 D. Solar Panel Anchorage 1. The solar panels shall be mounted in accordance with the most recent Sunmodo installation manual. If during solar panel installation,the roof framing members appear unstable or deflect non- uniformly, our office should be notified before proceeding with the installation. 2. The maximum allowable withdrawal force for a 5/16" lag screw is 235 lbs per inch of penetration as identified in the National Design Standards (NDS) of timber construction specifications. Based on a minimum penetration depth of 2'/2", the allowable capacity per connection is greater than the design withdrawal force (demand). Considering the variable factors for the existing roof framing and installation tolerances, the connection using one 5/16" diameter lag screw with a minimum of 2'/2" embedment will be adequate and will include a sufficient factor of safety. 3. Considering the wind speed, roof slopes, size and spacing of framing members, and condition of the roof, the panel supports shall be placed no greater than 48" on center. 4. Panel supports connections shall be staggered to distribute load to adjacent framing members. Based on the above evaluation, this office certifies that with the racking and mounting specified, the existing roof system will adequately support the additional loading imposed by the solar system. This evaluation is in conformance with the Washington State Residential Code, current industry standards, and is based on information supplied to us at the time of this report. Should you have any questions regarding the above or if you require further information do not hesitate to contact me. V truly yours, Scott E.Wyssli PE Washington License 111163 W GOA s G� H ' � � 20111163 40� �t<` �01STE4�O ��' ss�O.NAL r-'- Signed NSigned 10/27/2022 CONSULTING