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Kraus-Anderson Realty Company Project BL-11-01014 March 18, 2011 Page 12 limits of moisture vapor transmission that can be used to set schedules for flooring installation but, more importantly, may impact warranties. D.S. Exterior Slabs The exterior slabs will be underlain with a variety of soils, most of which are considered moderately-to highly-frost susceptible. If these soils become saturated and freeze, unfavorable amounts of heaving could occur. Grading to direct surface drainage away from buildings helps limit the potential for saturation and subsequent heaving to occur. Still,even limited amounts of movement can create tripping hazards to building residents,employees and guests. One way to help limit the potential for heaving to occur is to remove frost-susceptible soils present below the overlying slab "footprints" down to bottom-of-footing grades(42 inches to 48 inches), and replace them with non-frost-susceptible (NFS) backfill consisting of medium to coarse grained sands having less than 5 percent of the particles by weight passing a#200 sieve. Drainage should be provided at the base of the subcut and transitions from this subcut should be gradual (less than 3 horizontal: 1 vertical or flatter gradient). One alternative for reducing frost-related heave is to place at least 2 inches of extruded polystyrene foam insulation below the slabs and extend it approximately 4 feet beyond the outer edges of the slabs. The insulation may have to be buried below a cushion of sand or gravel to protect it during construction. Another alternative is to support the slabs on frost-depth footings, and suspending the slabs at least 4 inches above the underlying subgrade soils to accommodate heaving without it affecting the slabs. With the two alternatives mentioned above we recommend that differential frost heave should be accommodated at transition areas. D.6. Pavements Based on the borings, much of the area where paved areas will be constructed is underlain by existing fill soils overlying swamp deposits. Based on the standard penetration (N)values obtained during the soil borings, it appears that some compression of the swamp deposits in this area has occurred over time due to the weight of the fill soils. However,these soils may still be slowly compressing and the placement of additional fill soils in excess of 3 to 4 feet in these areas could result in further compression leading to pavement settlement.We recommend that placement of the bituminous wear course in parking and drive areas be delayed to allow for this settlement to occur. BRAUN INTERTEC