17. Provide a minimum footing width of 18 inches for continuous wall <br />footings and for isolated column footings. Place the base of all footings <br />at least 18 inches below the finished grade or paved surface, unless the <br />footings are poured monolithically with the slab. <br />18. Excavate for footings using a hoe equipped with a smooth bucket to <br />reduce subgrade disturbance. The excavations should be deep enough <br />to accommodate a minimum of 6 inches of compacted Select Fill <br />beneath the footing. Additional Select Fill may be required, depending <br />on actual site conditions and the amount of subgrade disturbance. <br />Excavations should terminate in medium stiff to stiff alluvium having a <br />minimum undrained shear strength of 0.4 tsf, or in imported granular <br />materials. The foundation subgrade for all buildings should be verified <br />by an FEI representative. <br />19. Overexcavate any unsuitable fill or debris encountered beneath footings. <br />Backfill the overexcavated areas using compacted Select Fill. If <br />needed, dewater the excavations prior to placing backfill. All footing <br />excavations should be evaluated by an FEI representative prior to <br />backfilling. <br />20. Use a modulus of subgrade reaction, ks, of 150 pci for floor slab design. <br />This value assumes the slabs will be supported on a minimum of <br />24 inches of compacted Select Fill underlain by undisturbed native <br />subgrade. Reinforce all floor slabs to reduce cracking and warping. <br />21. Provide a suitable vapor barrier under the slab that is compatible with <br />the proposed floor covering and the method of slab curing. The type <br />and placement of the vapor barrier depends on the method of slab <br />curing and schedule for installing the floor surfaces. Therefore, this <br />item should be reviewed by the flooring manufacturer, contractor and <br />project engineer and/or architect. <br />22. Provide a minimum of 6 inches of compacted Select Fill under all other <br />isolated concrete slabs and sidewalks, if this portion of the work occurs <br />during dry weather. Increase the thickness as needed to support <br />construction equipment during wet weather. <br />Drainage for Buildings <br />23. Install foundation drains along the perimeter of the . buildings. The <br />drains should consist of 3 or 4-inch diameter, perforated or slotted PVC <br />pipe wrapped in a Filter Fabric. The flowline of the pipe should be set <br />at least 18 inches below the ground surface. The pipe should be <br />bedded in at least 4 inches of Drain Rock and backfilled to within <br />6 inches of the ground surface with Drain Rock. The entire mass of <br />Drain Rock should be wrapped in a similar filter fabric that laps at least <br />12 inches at the top. <br />Oakleigh Meadows Cohousing February 12, 2013 <br />Geotechnical Investigation Project 2131004 <br />Eugene, Oregon 10. Willard C. Dixon Architect, LLC <br />1455 <br />