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© 2021 IronRidge, Inc. QuickMount L-Mount with Open-End Slot Certification Letter - 1 28357 Industrial Blvd Hayward, CA 94545 1-800-227-9523 www.IronRidge.com Attn: Corey Geiger, Global COO, Esdec Inc. Date: March 4th, 2021 Re: Structural Certification for QuickMount L-Mount with Open-End Slot This letter certifies the structural capacities of QuickMount L-Mount with open-end slot for use as a roof attachment for flush mounted PV solar systems. The L-Mount consists of an extruded aluminum L-foot with a vertical open-end slot, positioned above a 9” x 12” aluminum flashing. The L-Mount is fastened to an underlying roof rafter using a 5/16” x 4” lag screw or 5/16” x 4.5” structural screw. Full assembly details and component dimensions are shown in Exhibit EX-0020. The structural capacities of L-Mount are reviewed along three respective load directions including uplift, lateral parallel to the rafter, and lateral perpendicular to the rafter. The capacity ratings are based on structural load tests performed using a Universal Instron Test Unit according to ASTM D1761-20 “Standard Test Methods for Mechanical Fasteners in Wood and Wood Based Materials”. For each load test an L-Mount was installed onto a sample roof deck composed of 7/16” OSB Board over 2x4 rafters as shown in Figure 1. The moisture content and the specific gravity of the rafters were measured per ASTM D2395-17 “Standard Test Methods for Density and Specific Gravity (Relative Gravity) of Wood and Wood- Based Materials”. The recorded moisture content of the rafters among all sample roof decks is between 10% and 14%. For each load test, the point load was placed at the highest position allowed at the open-end slot. The failure observed under the uplift load was pull-out of the lag screw and structural screw at the peak load of 2693 lbs. and 2344 lbs., respectively. The results are the average of five (5) tests provided to each fastener condition. With a safety factor of 3.0 applied to the wood-based fastener pull-out, the allowable uplift capacity is 898 lbs. for L-Mount using the lag screw, and 781 lbs. for L-Mount using the structural screw. The above allowable capacity is applicable to roof decks with a rafter specific gravity greater than or equal to 0.50, which was recorded in the uplift load tests. For rafters with a lower specific gravity, the allowable uplift capacity shall be adjusted as described in Footnote 8 of Table 1. For the lateral load tests, two load directions (parallel or perpendicular to rafter) and two L-Mount orientations (vertical face of L-foot normal to the rafter or parallel to the rafter) were tested. The critical failure mode, which results in the lowest allowable lateral capacity, was observed be the L-foot yielding at the base of its vertical leg under a perpendicular lateral load. The average of the yield loads from five (5) lateral load tests is 425 lbs. With a safety factor of 1.65 per ADM -2015 for the aluminum yielding, the allowable lateral capacity is 258 lbs. for loads parallel or perpendicular to the rafter. The specified allowable lateral capacity shall be used when the supporting rafter has a specific gravity not less than 0.40, which was the average density recorded in the lateral load tests. Figure 1: L-Mount Assembly and Applied Loading Directions (using lag screw or structural screw). 417 S Clara St #2 04/17/23