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Determine the load which will be supported by the new supplemental beam in pounds per linear foot: Supplemental Beam Load (plf) = Existing Span (ft) x Total Floor Load (psf) _ 2 Note:Typical residential wood-framed construction may have an approximate floor load(15 psf dead load+40 psf live load)=55 psf total floor load M Determine the load on the interior SmartJack posts by multiplying the calculated supplemental beam load(plf) by the spacing of the SmartJack posts: SmartJack Load (lb) = Supplemental Beam Load (plf) x SmartJack Spacing (ft) Verify that the calculated SmartJack load is less than the allowable capacity provided by the various system components as well as the well-compacted crushed stone base and the bearing soils. Note:Without a detailed soil investigation,typical installations should assume no more than 1,500 psf allowable soil bearing pressure.This would equate to an allowable soil capacity of 6,000 lb for a 2'square cast-in-place concrete footing,a 2'cube of well-compacted crushed stone,or the 16"x 36"plate footing.Extremely soft soils may prohibit the use of a crushed stone base or plate footing and require that a larger concrete footing be utilized. Size the new supplemental beam by using the following table with both the SmartJack post spacing(ft)and the calculated supplemental beam load (plf).Choose a beam size that has an allowable load (plf)greater than the calculated supplemental beam load(plf)in step 1. Supplemental'Beam Allowable Load(plf)(Ij2,3j4) it SmartJack Post Supplemental Beam Size 4 ft 5 ft 6 ft 7 ft 8 ft Spacing (3)-2 x 8 1,170 750 520 380 290 i f i (3)-2 x 10 1,760 1,120 780 570 440 I Sawn (3)-2x12 2,360 1,510 1,050 770 590 } Lumber(s) (1)-4 x 6 850 550 380 280 210 i (1)-6 x 6 1,030 660 460 330 250 SmartJack HSS 4 x 4 x 0.120 2,720 1,740 1,160 730 490 Beams (1) This table makes no evaluation of the components of the existing structure. (2) Allowable loads in this table assume the supplemental beam is sufficiently restrained against lateral torsional buckling at an interval equal to or less than the SmartJack post spacing. (a) This table assumes serviceability deflection limits of 1/360 and 1/240 for live and total load respectively.It assumes a LL/TL ratio equal to 40/55.Other serviceability limits may need to be considered based on project requirements. (4) The new supplemental beam may be cantilevered overthe end support by a distance of 30 inches or by a distance of approximately 50%of the adjacent Smart lack spacing,whichever is less.Each beam segment must be supported by at least two Smart,lack posts. (5) Sawn lumber is assumed to be Douglas Fir Larch-No.2 or better. If the required supplemental beam size is undesirable,adjust spacing of the SmartJack posts and return to Step 2. ©2017Supportworks'' ~! Appendix4A All Rights Reserved 314 SmartJack®Systems