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_Da <br /> E n G i P E E R S <br /> E Washington <br /> v,' Oregon <br /> California <br /> cd, Texas <br /> Alaska May 28,2019 1"\ <br /> "apt � a `„3 ti i ar a4� <br /> Colorado II- S <br /> Montana City of Everett <br /> 3200 Cedar Street MAY 2 9 2919 <br /> Attn: Tony Lee and James Bronder <br /> CITY OF EVERETT <br /> Re: St.Mary Magdalen permit Services <br /> Plan Check Number B1902-008 <br /> Dear Mr. Lee and Mr. Bronder <br /> The following is our responses to your comments concerning structural issues in your comment letter <br /> dated April 22,2019. <br /> STRUCTURAL COMMENTS: <br /> 1. It appears that the proposed addition is utilizing Intermediate Reinforced Masonry Shear Walls <br /> a lateral force resisting system,which are currently not permitted per ASCE 7-10 for Seismic <br /> Design Category D. Please provide a lateral system that is permitted for the Seismic Design <br /> Category. <br /> DCI Response: A new lateral system has been selected. The new Seismic-Force <br /> Resisting System is a light-framed wood stud bearing wall with sheathing. R=6.5, <br /> Omega=3 and Cd=4. <br /> 2. Out-of-plane design details and permit calculations appear indicate that the exterior masonry <br /> veneer exceeds 12'-0"limit for wood construction support as well as exceeds the deflection of <br /> limit of L/600 per ACI 530-13 Sec 12.2.2.3.1.5. Please revise the designand calculations as <br /> required. <br /> DCI Response: The 12'-0"height limit per ACI 530-13 is for veneer that is vertically <br /> supported by wood framing (12.2.2.3.1.5). Our detailing is for the veneer to be <br /> vertically supported by the concrete footing at the bottom of the wall. The out of plane <br /> lateral support of the veneer, in our case the wood studs,need to have a deflection limit <br /> so as to "maintain the veneer stability". Our current drawings give the contractor two <br /> choices for the studs on grid 1. The worst case of those two options have a maximum <br /> lateral mid-height deflection of 1.16 inches at the tallest walls, approximately 33 feet. <br /> This gives a deflection of L/341 which we consider to be acceptable in maintaining the <br /> veneer stability. <br /> 818 Stewart Street,Suite 1000 Seattle,Washington,' 101 Phone(206)332-1900 <br /> Service Innovation Value <br />