915 WALL ST 2019-09-24 - Laserfiche WebLink

4 PRESCRIPTIVE RESIDENTIAL WOOD DECK CONSTRUCTION GUIDE Table 2. Maximum Joist Spans and Overhangs.' Joist Spacing (o.c.) 12" 16" 24" 12" 16" 24" Species Size Allowable Span2 (Li) Allowable Overhang3(Lc ) 2x66 9' 11 9' -0 7' 7" 1, _0" 11 1 1' - 3" 2x8 13' - 1" 11' - 10" 9' - 8" 1' - 10" 2' - 0" 2' -4" Southern Pine „ 2x10 16 -2 0”14 - 11 5" 1"3 - 3' -5" 2 - 10 2x12 18' -0"r 16' -6" 13' -6" 4' -6" 4' -2" 3' -4" 2x66 9' -6" 8' -4" 6' - 10" 0' - 11" 1' -0" 1' - 2" Douglas Fir- 2x8 12'-6" 11' - 1" 9' - 1" 1' -8" 1' - 10" 2' - 2" Larch, Hem-Pira 2x10 15' - 8" 13' - 7" 11' - 1" 2' - 10" 3' -2 2' -9" Spruce-Pine-Fir 2x12 18' -0"' 15' -9" 12'- 10" 4' -4" 3' - 11" 3' -3" 2x66 8' - 10" 8' -0 6' - 10" 0' -9" 0' - 10" 0' - 11" Redwood, Western Cedars, 2x8 11' - 8" 10' - 7" 8 - 8" 1 5" 1' 7" 1' _ 9" Ponderosa Pines, 2x10 14'- 11" 13' -0" 10' - 7" 2'-5" 2'- 7" 2' - 8" Red Pines 2x12 17' - 5" 15' - 1" 12' - 4 3' - 7" 3' - 9 3' - 1" 1.Assumes 40 psf live load, 10 psf dead load,No.2 stress grade,and wet service conditions. 2.Assumes L/360 deflection. 3. Maximum allowable overhang cannot exceed U4 or 1 of actual main span.Assumes cantilever length/180 deflection with 220 lb point load (See Figure 1A and Figure 2). 4. Incising assumed for Douglas fir-larch,hem-fir,and spruce-pine-fir. 5.Design values based on northern species with no incising assumed. 6. Ledger shall be a minimum of 2x8 nominal.Where guards are required,outside joists and rim joists shall be a minimum of 2x8 nominal. 7.Joist length prescriptively limited to 18'-0"for footing design. Figure 1A. Joist Span—Joists Attached at House and Bearing Over Beam. skating'wall one '. t n *can In -iiI M it * s►. R 9 1 -r.si rim pi* lcing .at ng n HH redlet Wald (fly ht b ) P 1 , rLI4 t. .span ��: l �um Tatiai: Pvarb a 06o I American Wood Council 17(:-.