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Page 2 of 2 <br />D.Solar Panel Anchorage <br />1.Concrete Tile <br />i.The solar panels shall be mounted in accordance with the most recent EcoFasten <br />installation manual. If during solar panel installation, the roof framing members appear <br />unstable or deflect non-uniformly, our office should be notified before proceeding with the <br />installation. <br />ii.The maximum allowable withdrawal force for a 5/16” lag screw is 229 lbs per inch of <br />penetration as identified in the National D esign Standards (NDS) of timber construction <br />specifications. Based on two screws with a minimum penetration depth of 2½”, the <br />allowable capacity per connection is greater than the design withdrawal force (demand). <br />Considering the variable factors for the existing roof framing and installation tolerances, <br />the connection using two 5/16” diameter lag screw with a minimum of 2½” embedment will <br />be adequate and will include a sufficient factor of safety. <br />iii.Considering the wind speed, roof slopes, size and spacing of framing members, and <br />condition of the roof, the panel supports shall be placed no greater than 48” on centers. <br />2.Composite Asphalt Shingles <br />i.The solar panels shall be mounted in accordance with the most recent Unirac installation <br />manual. If during solar panel installation, the roof framing members appear unstable or <br />deflect non-uniformly, our office should be notified before proceeding with the installation. <br />ii.The maximum allowable withdrawal force for a 5/16” lag screw is 229 lbs per inch of <br />penetration as identified in the National Design Standards (NDS) of timber construction <br />specifications. Based on a minimum penetration depth of 2½”, the allowable capacity per <br />connection is greater than the design withdrawal force (demand). Considering the variable <br />factors for the existing roof framing and installation tolerances, the connection using one <br />5/16” diameter lag screw with a minimum of 2½” embedment will be adequate and will <br />include a sufficient factor of safety. <br />iii.Considering the wind speed, roof slopes, size and spacing of framing members, and <br />condition of the roof, the panel supports shall be placed no greater than 48” 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 California Building Code, current industry standards, and is based on information <br />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 />Very truly yours, <br />Scott E. Wyssling, PE <br />California License No. 83664 <br />2307 N Towner St - <br />2017896310/18/2023