10721 19TH AVE SE 2023-04-07 - Laserfiche WebLink

Jeff Heilman, Development"Technician--Public Works Department RE: Owner: Wong— 1911'Avenue SE June 20 2018 'age 3/s7 9. 10. to only take the overturning for the shearwall above. This calculations is provided on sheet B- 14 of the calculations. The structural drawings specify proprietary Simpson-brand wood framing hangers. For example, see the "Joist&Beam Schedule" on Sheets S2.2 through S2.4. The sizes of the hangers are not specified. The structural drawings should be revised to specify the required hanger sizes. See IBC Section 107.2.1. The Joist and Beam Schedule on Sheets S2.2 and S2.3 have been updated to provide the specific hanger sizes. The design for the 2x10 roof joists on Sheet S2.4 over the stairway area is provided on structural calculation page B-4. The dimensions and support conditions in the calculations are not consistent with the drawings. The joist spans 21 feet, exceeding the 15-foot span in the calculations, and includes overhangs at each end. It is noted that Sheet S2.3 includes walls supported by framing at the third story that may be intended to provide intermediate supporting of the roof joists. If this is the intended load path,the roof framing shall be revised to evaluate the intended conditions. See IBC Sections 1604.2 and 1604.4. Calculation sheet B-4 has been updated. 1 l. Continuing with the previous comment, if the stairway roof framing is partially-supported by interior walls,the Type "Jl"joists and "B2" beams at the third floor on Sheet S2.3 shall be designed to support loads from the roof system in addition to loads at the third floor. Documentation for the design of this framing shall be submitted for review. See [BC Sections 1604.2 and 1604.4. Calculations have been added to analyze the joists and beam specified above. See sheets B-9 and B-17 of the calculations. 12. The third floor beam "B5" on calculation page B-13,and second floor beams "B2" and"B3" on calculation pages B-17 and B-19, respectively, support discontinuous shear walls. The following comments should be addressed: a) The overturning loads appear to be applied in a single direction. The loading conditions are not symmetric. Verify the loads have been reversed to evaluate reverse loading. See IBC Section 1604.4. b) It is not clear if the beams evaluate all load cases. For example,the third floor beam "B5" load schedule does not include roof snow and floor live loads. Verify that the beams include all applicable load combinations. See IBC Section 1605.3. c) It is not clear if the beams include all load values. For example,the third floor beam "B5" load schedule only appears to include a self-weight dead load. The weight of the roof, wall, and third floor framing does not appear to be included. The loads on the beams shall be verified. See IBC Section 1602.2. d) The seismic loads based on pages C-21 and C-24 appear higher than those in the beam calculations. Also, it appears that the "controlling tension loads" on pages C-21 and C-24 have been reduced by dead load resistance prior to applying the overstrength factor.