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12/29/2011 22:%30 PM FAX 2539849512 <br />inV I S S E a <br />B N 0 1 V E E R I N G <br />November 19, 2012 <br />Roland Jankelson <br />P.O. Box 98210 <br />Lakewood, WA 98496 <br />Sabin&KimW00DSfax <br />Re: 716 SE Everett Mall Way, Everett, WA <br />Existing Shortened Shear Wall <br />Visser Engineering Project #01-018 <br />Dear Mr_ Jankelson: <br />000 <br />Per your request I have reviewed our files and have visited the site to determine the structural impact of the <br />shortening of the type 2 shear wall indicated on our drawing S2.2, dated 3/16/2001. Based on our files, I believe <br />that the shear wall was designed as part of Phase 2 work that, to my knowledge, never occurred. Specifically, the <br />shear wall was designed in support of a future structural upgrade of the mezzanine to the south of the wall. <br />Reiterating our communications in 2001, it appears to us that the southern portion of the mezzanine was designed <br />for 100 psf retail loading,, and has never been suitable for light storage. It was our understanding that Phase 2 <br />would have brought the southern part of the mezzanine up to a rating of light storage — with the attendant seismic <br />impacts. <br />Evaluating the shear wall for the east -west loads on the not -upgraded southern mezzanine gives the following: <br />• A seismic weight of approximately 2000 sf x 15 psf = 30,000#, a design spectral acceleration <br />parameter, Sds, of 0.821, and a response modification coefficient, R, of 6.5, <br />• Which gives a southern mezzanine seismic load of approximately 3800#. <br />• The remaining shear wall is approximately 27 feet long, for a seismic shear stress of 140 plf —which is <br />far less than the capacity of any plywood / OSB shear wall. <br />Based on the foregoing, it is my opinion that the design basis for the shear wall — light storage in the southern <br />portion of the mezzanine — never occurred, thus the shear loads are substantially smaller, and the wall is adequate <br />as is. Note that the foregoing analysis is the same as that performed in the original design — it does not address the <br />northern portion of the mezzanine that was designed with the original building and is presumed adequate. <br />Please call if you have any questions <br />D IZ <br />Sincerely, <br />Vi3sli Engineering Company, Inc. <br />Mi ser, P.E., S.E. <br />32129 Weyerhaeuser Way S"th <br />Suite 103 <br />Federal Way . WA . 98001 <br />VOICE 253.935.0810 <br />PAX 253.835.0813 <br />