SmartLVL 15 Design Guide - Tilling Timber

STRUTTING/COUNTER BEAM SUPPORTING UNDERPURLINS &HANGING BEAM AS 4055 CLASSIFICATION N1, N2 AND N3ceiling mass - 20 kg/m 2Underpurlin'A' = Total ofunderpurlin spansCOUNTER/STRUTTINGBEAM'B' = Total ofrafter spansRoof StrutRoof AreaSupportedEXAMPLE:wind speed = N3sheet roof = 40 kg/m 2total of underpurlin span ‘A’= 5000 mmtotal of rafter span ’B’ = 4200 mmroof area supported = (A/2) x (B/2)= (5000/2) x (4200/2)= 5250000 mm 2 ( Convert to m 2 )= 5250000/1000000 = 5.25 m 2total of hanging beam span ’X’ = 4500 mmeffective beam spacing = ‘X’ / 2 = 4500 / 2 = 2250 mmstrutting counter beam span = 4500 mmStrutting CounterBeam SpanHangingBeam'X' = Total ofHanging BeamSpanEnter column at 3600 mm effective beam spacing, 6 m 2 roof area supportedand read down to a span greater than or equal to 4500 mmADOPT:SmartLVL 15 — 2/290x35Effective beam spacing (mm) 1800 3600Roof area supported (m 2 ) 2 4 6 8 10 12 2 4 6 8 10 12Member sizeDxB (mm)Roof mass(kg/m 2 )Maximum strutting beam span (mm)150x35 40 2750 2200 1900 1650 1400 1150 2450 2050 1800 1600 1350 115075 2350 1800 1500 1300 1150 NS 2150 1700 1450 1300 1150 NS170x35 40 3200 2600 2250 2000 1750 1450 2800 2400 2150 1900 1700 145075 2750 2150 1800 1550 1400 1200 2500 2050 1750 1550 1400 1200190x35 40 3600 3000 2600 2350 2150 1800 3200 2800 2450 2250 2050 175075 3150 2500 2100 1850 1650 1500 2900 2350 2050 1800 1650 1450200x35 40 3750 3200 2800 2500 2300 1950 3350 2950 2650 2400 2200 190075 3400 2700 2250 2000 1800 1650 3050 2550 2200 1950 1750 1600240x35 40 4350 3900 3600 3250 2950 2700 3950 3650 3300 3050 2850 265075 4050 3450 2950 2600 2350 2150 3750 3200 2800 2500 2300 21002/150x35 40 3550 2950 2600 2300 2100 1950 3150 2750 2450 2200 2050 190075 3100 2450 2100 1850 1650 1500 2850 2350 2000 1800 1600 15002/170x35 40 3950 3450 3050 2750 2500 2300 3600 3200 2850 2600 2400 225075 3600 2900 2500 2200 2000 1800 3300 2750 2400 2150 1950 18002/190x35 40 4300 3850 3550 3200 2950 2700 3900 3600 3300 3000 2800 260075 4000 3400 2900 2600 2350 2150 3700 3150 2800 2500 2300 21002/200x35 40 4450 4050 3700 3400 3150 2900 4100 3750 3500 3200 3000 280075 4150 3600 3100 2750 2500 2300 3850 3400 3000 2700 2450 22502/240x35 40 5150 4700 4350 4100 3900 3700 4700 4350 4100 3900 3750 360075 4800 4250 3850 3550 3250 3000 4450 4050 3700 3450 3150 29502/290x35 40 5900 5500 5100 4850 4600 4400 5400 5100 4800 4600 4400 425075 5600 5000 4600 4250 4000 3800 5150 4750 4400 4150 3900 37502/300x35 40 6050 5600 5250 5000 4750 4550 5500 5200 4950 4750 4550 440075 5750 5150 4700 4400 4150 3950 5300 4850 4500 4250 4050 3850SmartLVL 15 Design Guide 74