SmartLVL 15 Design Guide - Tilling Timber

UNDERPURLINS - SHEET AND TILED ROOFAS 4055 WIND CLASSIFICATION N1, N2 & N3Strutting beamUnderpurlinRafterspacingRoof strutRidge board'X' = Total of rafter spanseither side ofunderpurlinSpanSpan (backspan)Maximum cantilever = 1/4 allowable backspanMinimum backspan = 3 x actual cantileverEXAMPLE:wind speed = N3rafter spacing = 1200 mmroof load = 20 kg/m 2 (sheet roof)underpurlin span = 3500 mm (single span)‘X’ (total of rafter span) = 5400 mmroof load width = ‘X’ / 2 = 5400 / 2 = 2700 mmEnter single span table at 2700 mm roof load width column, 1200rafter spacing and read down to span equal to or greater than 3500mm in a 20 kg/m 2 rowADOPT:SmartLVL 15 — 170x58RLW = X/2 where ridge is struttedRoof load width (mm) 1800 2700 3600 1800 2700 3600rafter spacing (mm) 600 1200 600 1200 600 1200 600 1200 600 1200 600 1200Member sizeDxB (mm)Roof mass(kg/m 2 )Single spanMaximum Underpurlin span (mm)Continuous span90x35 20 2000 2000 1800 1600 1600 1200 2300 2500 1900 1900 1600 140060 1400 1200 1300 1000 1100 NS 1900 1900 1600 1500 1500 1300120x35 20 2700 2700 2400 2400 2100 2000 3000 3000 2500 2600 2100 210060 1900 1900 1600 1600 1500 1400 2600 2600 2200 2100 2000 2000130x35 20 2900 2900 2600 2600 2300 2200 3300 3200 2700 2700 2300 220060 2100 2000 1800 1800 1600 1500 2800 2800 2400 2400 2200 5 2100 590x42 20 2200 2200 1900 1900 1700 1400 2600 2700 2100 2000 1800 180060 1500 1400 1300 1100 1200 1000 2000 2000 1800 1800 1600 1400120x42 20 2900 2900 2500 2600 2300 2200 3400 3300 2700 2700 2300 250060 2000 2000 1700 1700 1600 1500 2700 2700 2400 2400 2100 2100130x42 20 3100 3100 2700 2800 2500 2400 3600 3500 2900 2900 2600 260060 2200 2200 1900 1900 1700 1700 3000 3000 2600 2600 2300 2300140x42 20 3300 3300 2900 2900 2700 2600 3900 3800 3100 3100 2700 280060 2300 2400 2100 2000 1900 1900 3200 3100 2800 2800 2500 5 2500150x42 20 3600 3500 3200 3100 2800 2800 4100 4100 3400 3300 2900 290060 2500 2600 2200 2200 2000 2000 3400 3400 3000 3000 2700 10 2700 1090x58 20 2400 2500 2100 2100 1900 1900 3000 3000 2500 2600 2100 210060 1700 1600 1500 1300 1300 1100 2300 2200 2000 1900 1800 1800130x58 20 3400 3400 3000 3000 2800 2800 4300 4300 3500 3400 3000 300060 2400 2500 2100 2100 1900 1900 3300 3200 2900 2900 2600 2600150x58 20 3900 3900 3500 3400 3200 3200 4900 5000 4000 4000 3400 330060 2800 2800 2500 2500 2200 2200 3800 3800 3300 3300 3000 3000170x58 20 4400 4400 3900 3900 3600 3600 5500 5500 4400 4400 3800 380060 3200 3100 2800 2800 2500 2600 4300 4300 3800 3700 3400 3400200x58 20 5200 5200 4600 4600 4200 4200 6000 6000 5200 5200 4500 440060 3700 3700 3300 3200 3000 3000 5000 5100 4400 4400 4000 15 4000 15300x75 20 6000 6000 6000 6000 6000 6000 6000 6000 6000 6000 6000 5 6000 560 6000 6000 5300 5300 4900 4900 6000 6000 6000 5 6000 5 6000 30 6000 30NOTES:1. D = member depth, B = member breadth, NS = not suitable.2. Maximum cantilever = 1/4 allowable backspan3. Minimum backspan = 3 x actual cantilever4. End bearing length = 45 at end supports and 45 mm at internal for continuous member. Subscript values indicate the minimum additional bearinglength where required to be greater than 45 mm at end support and 45 mm at internal for continuous member5. Not all sizes of SmartLVL 15 in this table are stocked in each state. (F17 sizes of 120, 140, 190 and 290 mm depths not currently stocked in WA). Pleasecheck with your supplier before orderingSmartLVL 15 Design Guide 64