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1978, 08-30 Permit: M7065 Inspect x , ROBERT B. HYSLOP 3 j STRUCTURAL ENGINEER N 2913 West Oval, SPOKANE,WASHINGTON 99205 s • August 28, 1978 Mrs. Donald G. Friske Key Home, Inc. P. 0. box 96 Veradale, Wastj. 99037 In response to your request, I made an inspection this morning, in the company of your husband, of the house under construction at S 1715 Ridgemont Drive, in the Spokane Valley. The specific problem was a crack in the rear (east) •oncrete foundation wall. This rear walliis 75 feet long, 7'-8" high and 8" thick. It has a spread footing under what will be the basement floor, and a wood sill at the top, anchored into it with sheet metal anchors at 6 ft. centers. The trussed wood jbbsts of the first floor bear on the sill and are nailed thereto. The end walls of the house join with this rear wall at each corner. An exterior wood deck is being built on the outside, a bit below first floor line. Backfill is some three feet or so below that, and is to be finished to grade away from the wall to the rear, with crawl space under the deck. There is one crack, roughly vertical, at 27 ft. from the south end of the 75 ft. wall. It is between 1/16" and 1/8" its full length, the same outside as inside. The wall is reported to have light horizontal reinforcement and no vertical steel. The nature of the crack indicates that it is caused solely by concrete shrinkage. It is vertical, which rules out unequal soil bearing, and uniform top to bottom, indicatikg no case of soft or hard spots in the bearing. It is equal inside and outside, indicating no cause of bending, as due to backfill pressure. It is relatively near t7 11 E EDUILp GCODS D r' PD 1978ET Friske p.2 Aug. 28, 1978 AUG 3 0 '.973 the center of the length of the wall, where the first shrinkage crack should be expected, and its location is likely that of a series of reinforcement ends. It is a natural and common defect of concrete construction, sometimes avoidable by carefully designed and quite heavy reinforcement. It causes no structural hazard, and no damage except its appearance and its invitation to water leakage. A. good job of elastic calking will seal against that. In this case, with the wood deck above, no irrigated planting next to the wall, and the grade finished to drain away from the wall, there should be no reason for leakage. There is a similar crack in the front (west) concrete wall, 6" thick and 3'-4" high under a row of windows. Here there may be planting next to the wall, and a good job of grooving and calking is advisable. i )44,./47 Robert B. Hyslop Structural Engineer (6 11' A;11, ' Pio. 2195 J f s \\. 4 H I N GI'D\ •.4.,'i •