9205 4TH AVE W 2025-12-03 - Laserfiche WebLink

July 2, 2008 Duplex Buildings L&A Job No. 8AO67 Page 11 BUILDING FOUNDATIONS Conventional footing foundations may be used to support the proposed duplex buildings. The footing foundations should be placed on or into the underlying, very -dense fresh till and/or advance outwash soils, or on structural fill placed over these undisturbed competent basal soils. Water should not be allowed to accumulate in excavated footing trenches. Disturbed soils in footing trenches should be completely removed down to native fresh till and/or advance outwash soils prior to pouring concrete for the footings. If the above recommendations are followed, our recommended design criteria for footing foundations are as follows: • The allowable soil bearing pressure for design of footing foundations, including dead and live loads, should be no greater than 3,000 psf if constructed on or into very -dense fresh till and/or dense advance outwash soils, and no 'greater than 2,500 psf if constructed on structural fill placed over the above competent basal soils. The footing bearing soils should be verified on -site by a geotechnical engineer after the footing trenches are excavated and before the footings poured. • The minimum depth to bottom of perimeter footings below adjacent final exterior grade should be no less than 18 inches. The minimum depth to bottom of the interior footings below top of floor slab should be no less than 12 inches. • The minimum width should be no less than 16 inches for continuous footings, and no less than 24 inches for individual footings, except those footings supporting light -weight decks or porches. A one-third increase in the above recommended allowable soil bearing pressure may be used when considering short-term, transitory, wind or seismic loads. For footing foundations designed LIU & ASSOCIATES, INC.