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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 K2 Systems 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 5/16” lag screw is 298 lbs per inch of penetration as <br />identified in the National Design Standards (NDS) of timber construction specifications. Based on <br />two screws with a minimum penetration depth of 2½”, the allowable capacity per connection is <br />greater than the design withdrawal force (demand). Considering the variable factors for the existing <br />roof framing and installation tolerances, the connection using two 5/16” diameter lag screw with a <br />minimum of 2½” embedment will be adequate and will include a sufficient factor of safety. <br />3. Considering the wind speed, roof slopes, size and spacing of framing members, and condition of <br />the roof, the panel supports shall be placed no greater than 72” on center. <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 2022 CRC, current industry standards and practice, and is based on information supplied <br />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 />Very truly yours, <br />Scott E. Wyssling, PE <br />California License No. 83664 <br />2960 S Greenville <br />St Unit B - <br />2017942605/04/23