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d. The design loads for the elevator system, including impact loading, should be <br /> specified in the"Elevators"section of the Structural General Notes. At a <br /> minimum, estimated design loads should be specified for the design, and verified <br /> when the elevator design drawings are submitted for review. See IBC Sections <br /> 1603.1.8 and 1607.9.1. <br /> 8. The Roof Framing Plan on Sheet S1.5 shows an elevator hoist beam at Grid A.571.5'- <br /> 1/9'. Detail 3/S1.5 shows the connection detail between the beam and the supporting <br /> wood-framed wall, consisting of (2) 3/8"lag bolts into the narrow face of a 2x12 ledger. <br /> Framing connections are required to provide a minimum positive connection capacity per <br /> ASCE 7-10 Section 1.4.4. Per the 2015 NDS Table 12.5.1C, the minimum edge distance <br /> for the lag bolts must be 4D=1.5 inches. The connection cannot provide the required <br /> capacity and must be revised. See IBC Section 2306.1 and 2307.1. <br /> 9. Detail 3/S1.5 indicates maximum hoist beam load of 5 kips. The following comments <br /> should be addressed: <br /> a. Clarify if the load shown is the maximum beam load at or near the center of the <br /> beam, or the maximum reaction. If the latter, the maximum beam load should <br /> be specified. <br /> b. The maximum beam load should be specified in the Structural Notes on Sheet <br /> SO.1 in the section titled "Elevators". See IBC Sections 1603.1.8 and 1607.9.1. <br /> c. Documentation substantiating the design of the hoist beam should be submitted <br /> for review. Based on a presumed maximum load of 10 kips at the center of the <br /> beam and an unbraced length of 10 feet, the beam does not appear to have <br /> sufficient capacity. See IBC Section 1604.2. <br /> 10.The Fourth Floor includes concrete floor infill between Grids E-F/2-3. The drawings are <br /> not clear if the infill is being placed in a pre-existing opening, or if demolition of existing <br /> elements is required. Please clarify. If demolition of existing elements is required, <br /> additional documentation should be submitted for review indicating the work to be <br /> performed. See IEBC Section 106.2.1. <br /> 11. Details 1/S1.4 and 3/S1.4 indicate the construction of a concrete infill beam along Grid <br /> F. Calculations substantiating the design of the beam, including its connections for <br /> transfer of shear and flexural forces, should be submitted for review. Note that it <br /> appears the infill is intended to restore the original beam spanning between Grids 2 and <br /> 3, and therefore the existing beam sections must also be evaluated and shown to meet <br /> current standards. Also, all beam-column frames in the building appear to be moment <br /> frames, and therefore the total design loads must include lateral forces. See IBC <br /> Sections 1604.2, 1604.4, and 1901.2. <br /> 12.The infill area between Grids E-F/2-3 consists of a 3.5-inch thick concrete topped metal <br /> deck that spans 7.5 feet. The span appears to exceed the limits of the proposed deck. <br /> Documentation substantiating the deck design, including deflections, should be <br /> submitted for review. See IBC Section 1604.2. <br /> 13. Details 1/S1.4 and 2/S1.4 show the support conditions for the Fourth Floor slab infill at <br /> Grids E-F/2-3. Calculations substantiating the design of the connections, and in <br /> CITY OF EVERETT • 3200 Cedar Street • Everett, WA 98201 • (425)257-8813 Page 4 <br />