1212 GRAND AVE 2016-01-01 MF Import

March 31, 2008 Mr. Paul Tessier L&A Job No. 8A027 Page 14 Building Footing Drains A subdrain should be installed around the perimeter footings of[he additions and new garage to minimize accumulation of groundwater under them. T'he subdrains should consist of a 4-inch- minimum-diametcr, perforated, rigid, drain pipe, laid a few inches below the bottom of perimeter footings. T'he trcnches and the drain lines should have a sufficient gradient (0.5 percent minimum) to gcnerate flow by gravity. The drain lincs should be enclosed in washed gravel and completely wrappcd in non-woven tilter fabric to within about 12 inches of finish grade. The remaining trenches may be backfilled with on-site impervious soils. Water collected by the footing drain systems should be tightlined, separately from the roof and surface stormwater drain systems, to discharge into a nearby storm sewer. Surfacc Dreinagc Water should not be allowed to stand in any areas whcre footings, slabs, or pavement is to be constructed. Finish ground surfuce should bc graded to flow away from the existing housc, the additions and the new garage. We recommend the finish ground be sloped at a grndicnt of 3 pa:rcent minimum for a distance of at lcast 10 feet away fiom the buildings, except in lhe areas to bc paved. Clcanouts Su�cient number of cicanouts at strategic locations should be provided for the underground dmin linc syslcros. "1'hc undcrground dr�in linc systcros should bc maintained periodically to prcvcnt dogging. Building Setback Thc putposc of building sctback trom thc top or toc or an ovcrly stcep portion of a slopc is to establish a safe bullcr such that if'a sloEx failure should occur the stability of the structure can be LIU & ASSOCIATES, INC. i�., , ;.