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2. The submitted detail does not address connection of the floor framing to the north wall framing. There is a <br /> triaxial loading condition (i.e., vertical shear for gravity, transverse shear for diaphragm forces, and tension due. <br /> to out-of-plane loading on the wall). This issue was raised in the review comments, but was not adequately <br /> addressed. As such, redlines were provided to fill in the gaps; this was a last resort to allow the project to <br /> proceed to construction. At this point, we need a detail substantiated by analysis that create(s) a code <br /> compliant connection; we will not perform redlines this time to expedite approval. The connection must be <br /> designed for concurrent loading as outlined above. In response to the comments below regarding load transfer <br /> to the studs,this does not provide a complete load path. The studs require blocking for rotational stability and <br /> load transfer to the wall sheathing to complete the load path. <br /> a. Blocking added for torsional stability. <br /> b. Calculations added for triaxial loading condition. Combined loading is well below 1.0 demand/capacity <br /> ratio, as expected. <br /> c. Details updated attached for clarity. No red-lines requested. <br /> 3. Continuing with the previous comment, the floor connection on the south wall has the same triaxial loading <br /> condition and similar load path issues. It too must be designed and properly detailed to transfer concurrent <br /> loading through a valid load path. <br /> a. The south wall connection is slightly different. The floor diaphragm connects right at a continuous 6x12 <br /> beam running the full length of the building. The joist connection will be the same. As demonstrated <br /> above, the dynamic loads on these connections are very low resulting in a triaxial DCR well below 1.0. <br /> The detailing is the exact same. The 6x10 beam has been analyzed for out of plane bending and is <br /> capable of transferring the loads from the wall and into the floor diaphragm. This analysis was <br /> submitted previously and either ignored or not reviewed. <br /> 4. The windows in the upper floor should have at least one king and one jamb stud; this may occur—I don't recall <br /> the construction at this point. Note that the king studs are effectively supporting loads for an 8-foot opening, <br /> not 4-foot, as continuous studs are missing on both sides. The use of a single king stud on each side of a 4-foot <br /> opening is based on only a 2-foot tributary width (i.e., one-half of the window width) going to each king <br /> stud. These king studs will received at least 2-tributary feet from both sides. It is recommended that solid <br /> framing be installed as redlined in the drawings. <br /> a. All of the 4 ft windows have at least 1 king stud on each side. Two of the windows have a single king stud <br /> between the new window opening and the infill areas. Calculation added to show that a single king stud <br /> is fine for c&c wind pressures with 8 ft tributary area. <br /> 5. Continuing with the previous comment,the sheathing on the outside of the south wall appeared very patchwork <br /> and dubious as far as being able to perform as required. It was also noted that the sheathing was a combination <br /> of plywood and OSB of unclear structural capability. Solid panels matching the requirements in the approved <br /> construction drawings should be used in the construction. <br /> a. Both OSB and plywood meet the requirements for structural shear wall sheathing. The reviewer has <br /> provided no code references to indicate that the 2 cannot be used together. Solid panels were used in <br /> all infill areas. SPDWS 4.3.7.1.1 States that "4x8 panels shall be used except at boundaries and changes <br /> in framing. All edges of all panels shall be supported by and fastened to framing members or blocking." <br /> This is a change in framing and we clearly meet this requirement. <br /> The shear demand on these walls is 31 lbs per ft.These walls do not require any blocking. As perforated <br /> shear walls, the infill areas could have been left completely open and we would still not be anywhere <br /> near the capacity of the shear walls and would still have zero net uplift. As the engineer of record, I have <br /> inspected these walls and found them to be more than adequate. <br /> Thanks, <br /> Jon Conner PE,SE <br /> Structural Engineer I Lakeview Structural Engineering <br /> 1802 Amanda Ave <br /> Gold Bar, WA 98251 <br /> C: 206.914.9536 <br />