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4rl NORry1i, t�n t(tvirRthoc• PACIFIC NORTHWEST ENGINEERING,INC. The Cornerstone Foundation System, Smart Foundation RB-54 precast concrete panel (SF RB54) has been tested by Umpqua Testing Material and Quality Control Service. (See the attached letter dated December 20, 2010 from "Umpqua Testing Services, LLC sheets 1 to 3) Results of the test confirm that the (SFRB-54 & SFS60) precast concrete wall can provide continuous support to the perimeter wall for a HUD code home of 9,210 lbs. per lin. foot. If a higher perimeter support is required, wedge sets placed at 9" on centers would provide as much as 18,420 lbs. per lin. foot. As noted in the attached testing report the yield point was for the loading at the "support wedges" and not that of the concrete panel bearing on the footing. Therefore the largest point load (4,500 lb) could be easily supported by the allowable (9,210 lb) even with a factor of safety of 2.0. It is our recommendation that the added two (2) wedges be placed at each anticipated point load exceeding 3,000 lb on the perimeter of the building. Lateral Resistance to Wind Loading The test data reveals the SFRB-54 (& SFS-60) foundation system allows manufactured home units to resist wind loads of nineteen point nine (19.9) psf or the design load of the F manufacture home unit. This meets or exceeds all code requirements. �r The attached calculations (sheets show the required maximum wind loading for an exposure "C" with 100 mph winds. The calculations are first based on a single (12'-0" wide) by seventy (70'-0") foot long home. This was chosen because the maximum loading is perpendicular to the long axis and seventy (70'-0") long will yield the maximum loading on the minimum resistant system (the 12'-0" direction). The calculations are then based on a triple (37'-0") wide building. This will allow triple (+/-) the loading in the side to side (gable end to gable end) direction. It should be noted the single wide had the greatest load in a front to back direction. The SF RB-54 (SFS-60) foundation System uses steel plates and fasteners to connect the home, the foundation wall and the footing all together. The design uses the end walls to calculate load resistance and the longitudinal walls for calculating the load required. Each connector has a listed capacity of 700 lbs shear. Both end walls of a 12 ft. wide home would have a total of 14 bottom connectors of 700 lbs. each for a total wind shear resistance of 9,800 lbs. As shown in the test results "The SFRB-54 (& SFS-60) foundation System" has a test proven load capacity of 700 lbs. / lin. ft. (For a single wide 12'-0" unit the total shear loading capacity is 700 X 14=9,800 lbs total allowable load divided by 12'-0" =817 plf) at each of the two end walls. The empirical testing proves the listed, and anticipated, 4242 Silver Falls Dr. N., Silverton, OR. 97381 ph #(503) 873-3184 fax# (503) 873-3907 P.E.# 13,676