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Detail 8/S3.1 is for cases where the holdown strap from above lands over an opening <br />and is called out on sheet S5.0. Detail 9/S3.1 is when a holdown lands on a steel beam. <br />The detail is called out on sheet S5.0 on Grid G. <br />In ASCE 7-10, 12.10.2.1, exception 2, it states that the overstrength factor is not <br />required in light framed shearwall construction. Therefore, the wood headers will not <br />require an overstrength factor from the seismic loads from above. Most of the <br />beams/headers were controlled by deflection so the overstrength factor does not affect <br />them because it applies only to bending and shear stress. <br />4. Please verify that the out -of -plane anchorage forces are accounting for the <br />increase in anchorage force per ASCE 7-10 Section 12.11.2.1 for flexible <br />diaphragms. <br />Components and Cladding wind controls the out of plane loads to the wall and the <br />minimum diaphragm forces controls the anchorage design for in plane loads for the <br />structure. A calculation has been attached verifying this. <br />5. On page 13 of 150 of the permit calculations, it appears that chord forces are <br />4.4kips in one direction. Please verify that the wood members that are resisting <br />this load can resolve 4.4kips in addition to any gravity loads present as per the <br />applicable load combinations. Please verify if this is an ultimate or allowable load <br />demand. <br />Double 2x6 top plates are sufficient for handling the tension and compression loads <br />from the diaphragm. However it was noted that the top plate splice nailing was not <br />shown on detail 1/S2.1. A note has been added to the detail for top plate splice nailing. <br />A calculation sheet has been attached as well. All of the loads for the lateral design are <br />allowable loads because the timber was designed using Allowable Stress Design <br />(ASD). <br />6. It appears that the drag strut designs are based on an arbitrary increase of 25% <br />increase in design demand. Per Section, 12.10.2 of ASCE 7-10, the collector <br />designs are required to use the overstrength factor (a) in design of the drag strut. <br />Please clarify and revise drawings as required. <br />Per ASCE 7-10, 12.10.2, exception 2, it states, "In structures or portions thereof braced <br />entirely by light -framed shear walls, collector elements and their connections including <br />connections to vertical elements need only be designed to resist forces using the load <br />combinations of Section 12.4.2.3 with seismic forces determined in accordance with <br />Section 12.10.1.1 ". Therefore, we do not need to design for overstrength since we <br />designed with the diaphragm forces per 12.10.1.1. The 25% increase comes from <br />