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Exterior Wall <br />Sloped To Drain Away <br />From Structure <br />I I— <br />Wall Drainage Material <br />Pavement Or 24" —� <br />LowPermeabilitySoil /�� IIIIII=III <br />2' Min. <br />Retained Soil <br />Damp Proofing/Water Proofing <br />Geocomposite Drainage Board Per Others <br />Temporary <br />Excavation Slope <br />Vapor Retarder <br />_ <br />Floor Slab <br />Geotextile Filter Fabric <br />4" <br />12" Min. Cover Of <br />Capillary Break <br />Drainage Material (6" <br />Min. On Sides Of Pipe) <br />4" Diameter <br />Perforated Drain Pipe <br />Not To Scale <br />ILYAU1:1 Uab71 <br />A. WALL DRAINAGE MATERIAL <br />May consist of washed %-inch to No. 8 pea gravel per Section 9-03.1(4)C Grading No. 8, or conform to Section 9-03.12(4) of the 2018 <br />WSDOT Standard Specifications provided the drainage material is surrounded by a non -woven geotextile fabric such as Mirafi 140N (or <br />approved equivalent). The wall drainage material should be covered with 2 feet of less permeable material, such as the on -site silty <br />sand that is properly moisture conditioned and compacted. A geotextile separator should be placed between the wall drainage material <br />and overlying cover soil. <br />B. RETAINED SOIL <br />Should consist of structural fill, either on -site soil or imported. The backfill should be compacted in loose lifts not exceeding 6 inches. <br />Wall backfill supporting buildingfloor slabs should consist of imported sand and gravel per WSDOTStandard Specification 9-03.14 <br />compacted to at least 95 percent ASTM D1557. Backfill not supporting buildingfloor slabs, sidewalks, or pavement should be <br />compacted to 90 to 92 percent of the maximum dry density, per ASTM D1557. Backfill supporting sidewalks or pavement areas should <br />be compacted to at least 95 percent in the upper two feet. Only hand -operated equipment should be used for compaction within 5 feet <br />of the walls and no heavy equipment should be allowed within 5 feet of the wall. <br />C. CAPILLARY BREAK <br />Should consist of at least 4 inches of clean crushed gravel meetingthe gradation of WSDOTStandard Specification Section <br />9-03.1(4), AASHTO Grading No. 67, or clean crushed gravel meetingthe gradation of Seattle Mineral Aggregate Type 28 <br />D. PERFORATED DRAIN PIPE <br />Should consist of a 4-inch diameter perforated heavy -wall solid pipe (SDR-35 PVC) or rigid corrugated polyethylene pipe (ADS N-12) or <br />equivalent. Drain pipes should be placed with 0.25 percent minimum slopes and discharge to the storm water collection system. <br />Foundation Drainage <br />7800 Evergreen Way <br />Everett, Washington <br />GWENGINEERS� Figure3 <br />