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2915_001.pdf13228 NE 20" Street, Suite 100, Bellevue, WA 98005-2049 Phone (425) 614-0949 Fax (425) 614-0950 Bellevue, WA I New York, NY October 15, 2019 RE: Edmonds Crossing Apartments I Building Department Review — Structural Comments AUE No: 18456 To whom it may concern, The following is a summary of responses to the Building Department Review — Structural Comments for the Edmonds Crossing Apartments project. Comments are fisted i- ualiCs and responses are listed in red. Structural Review Comments: Sl: Sheet SO] a) Soils report statement indicates "NIA ". Please verify that the Geolech report has been reviewed and that the design complies with its requirements. Geolech report submitted is by Gary A Flowers PLLC datedJune 8', 2019 (IBC 107) The soils report has now been reviewed and reference by ALE in the revised "Footing and Foundation Loading" section of the General Notes on sheet SO I. b) Concrete notesforplacing duringfreezing weather referenced ACI 318-5.12 and 5.13. The sections do no appear to be valid. Please verify the current A CI 318-14 edition is used Please revise the code sections (A CI 318, JBC Chapter 35) Code references have been updated to 26.5.4 for Cold weather requirements. Code reference has been updated to 26.5.5 for Hot weather requirements. Remaining code references have all been updated accordingly. c) Framing note: Reference is made to 7-2304.9. ]for nailing schedule. The current reference may by T2304.10.1 Please verify andupdate all code references to the current IBC 2015. (IBC 107) Code reference to intended Table T2304.10.1 has been updated in "Conventional Structural Lumber" section of the General Notes on sheet SO]. Remaining code references have been updated accordingly. d) Please provide deferred submittals list on the cover sheet clearly identifying items that are provided by others. Please coordinate this list with the architectural list of deferred items. (IBC 107) 0 AUE does not require any structural items to be part of a deferred Submittal. As a result, this section was omitted from the General Notes. S2: Sheet S02 a) Please provide statement of special inspections identifying thefollowing: (IBC 1704.3. 1) i. The materials, systems, components, and work required to have special inspections. it. The type and extent of each special inspection iii. The type and extent of each test. iv. Additional requiremenisfor special inspections or testsfor seismic or wind resistance as specified in Sections 1705. v. For each type ofspecial inspection, identification as to whether it will be continuous special inspection, periodic special inspection, ofperformed in accordance with the notation used in the referenced standard where the inspections are defined. vi. For steel special inspections, please provide the requirementsftom AISC 360 Chapter N (IBC 1705.2. 1) 0 See added special inspection tables on sheet S02 that address the above required information. S3: Sheet S1 I a) Geotech report recommends using 10 Mil vapor barriers. The plan shows 8 mil vapor barriers. Please verify and revise (Geo report) 0 The vapor barrier callout on S I I has been updated to match the geotechnical report S4: Sheet S1 2 a) A beam member has not been clearly identified. Please verify and provide the information (JBC 107) 0 Intended beam callout has been added to plan sheet S12. b) The jogs of the building disrupt the continuity of the top plate chords. Please verify that the chord or sub chord exiendsfar enough into the adjacent diaphragm to develop the axialforce through shear transfer. This may require additional blocking and strapping. Diaphragm sheathing to resist direct tension or compressionforces is not permitted. (ASCE 7-10 1.4, lZ 1. 3, 12.1.4, 12. 10, and 12.11.2.2) 0 AUE has reviewed the chords and sub -chords and the current system is adequate to develop the axial forces through shear transfer RESUB NOV 18 2019 BUILDING DEPARTMEN-1 CITY OF EnMONDS c) The structure appears to have horizontal nonparallel system irregularity. Please verify that the requirements of ASCE 7 T12.3-1 are satisfied. A 3D model may be necessary. (ASCE 7 T12.3-1) It is AUE's opinion that a 3D model of the building is not necessary, The building consists of a flexible wood diaphragm at each level. The flexible diaphragm allows AUF to comfortably predict the distribution of lateral loads accordingly to the vertical lateral load resisting systems. The diagonal shear wall triggering the horizontal irregularity has been analyzed under the requirements of section 12.5.3.a of ASCE 7-10, which constitutes that the orthogonal loads in each direction be combined for the analysis of this type of irregularity. Section 12.5.3.a states to follow the requirements of Section 12.5.1 which requires the element to be designed for 100% of the force for one direction plus 30% of the other direction. AUE has fully combined both directions of loading to this wall to be conservative, d) Loadpathfor diaphragmforces is unclearfor thefollowing markedarea. No shearwalls have been shown in this region. Please verify if collectors are to he used of if walls in the storage area are shearwalls (IBC 1609, 1613) Please see the revised plans where shear walls have been added at the storage room area. e) Some of the woodftaming at decks may be exposed to weather. Please verify that they are ofdurable material It is unclear on the drawing (IBC 2304.12) 0 Wood framing at decks are enclosed by Architectural finishes. Treated framing will not be required. S5: Sheet Sl 3 a) The structure appears to have horizontal reentrant corner irregularity. Please verify that the increase load requirements ofASCE 7 12.3.3.4 have been satisfied (ASCE 7 T12.3.1) Please see the revised plans where shear walls have been added. With the addition of the shear walls the building extensions are now laterally supported on all four sides. We are not transferring forces through the re-entrant comers so the increase load requirements of the mentioned section of ASCE 7 do not need to be applied. S6: Sheet S21 a) Detail 12: Thefooling schedule reinforcing may not meet the requirements ofACI 318. Please verify that minimum steel isprovided (ACI 318 7.6. 1. 1) 0 The footing schedule reinforcing has been verified that it meets the minimum requirements of ACI 3 18. S7: Sheet S41 a) Detail 5,6: Decks shall be positively anchored to the primary structure. Use of diaphragm sheathing to resist direction tension or compression forces is not permitted. Please verify and add tension devices and blocking to transfer loads to interiorfloor diaphragm. (IRCF507.2.3)(ASCE7]2.11.2.2, 1.4, 12.1.3, 12.10) 0 Please see the revised details 5 and 6 .vIiere tension devices have been added at the deck to main floor framing interface. S8: Sheet S42 a) Detail 5,6, 7: Diaphragm shown are disconlinuousftom primary diaphragm. Cross grain bending may occur at ledger. Hangersface nailed to the ledger may also experience pull outforces. Please consider providing tension devices and blocking at suitable spacing (ASCE 7 12.11.2.2. 1,4. 12.1.3, 12. 10) 0 Please see the revised details 5A and 7 where tension tie devices have been added. S9 and G16 a and b: Sheet S43 a) Detail 5: See also correction (319 andprovide coordination of detailing. i. Please verify that P-2 "of soil weight has been accounted in the gravity or seismic analysis (ASCE 7 12.7.2) ii. Please verify woodframing are not in direct contact with soil (IBC) iii. Please verify that rafters and diaphragm are tied to wall studs with tension device. Cross grain bending may occur at ledger. Ledger may also experience pull outforces (ASCE 7 12.11.2.2) • i. The 1 '-2'- of soil has been accounted for in the gravity and seismic analysis. • ii.The wood framing is not in direct contact with the soil. The Architect is specif�ing a water -proof membrane at this location. • iii. The ledger shown in this detail is for gravity Support of the entrance canopy framing. The lateral loading is dealt with the via the sheathed roof diaphragm of this area distributing the loads to the supporting wood beam at the second and third floor level. I r�li =14 1) Detail 6: Please verify condition at party ivall. They do not appear to be continuous. It is unclear how the diaphraginforces are resolved Please verify loadpaths. Allportions of the structure shall be designed and constructed to act as an integral unit in resisting seismicforces unless separated structural by a distance sufficient to avoidpounding effects. (ASCE 7 12.12.3) Please see the revised plans where a shear wall has been added to deal with the concern of diaphragm forces. Blocking has been added between the party walls to ensure that this area will not succumb to pounding forces. Please feel free to contact me if you have any questions regarding this narrative. Sincerely, AUE Mitchell Beck, P.E. Senior Project Engineer JAOU E I