TYPICAL TIMBER SIZES FOR DOMESTIC HOUSES ALL DIMENSION DEPTH X WIDTH BEARERS SUPPORTING FLOOR JOISTS ONLY BEARER SPACING 1800 2400 3000 3600 BEARER SPAN 1500 1800 2100 2400 2700 3000 3300 3600 1500 1800 2100 2400 2700 3000 3300 3600 1500 1800 2100 2400 2700 3000 3300 3600 1500 1800 2100 2400 2700 3000 3300 3600 USE SEASONED F7 120X70 120X70 140X70 170X70 190X70 220X70 240X70 240X70 120X70 140X70 170X70 190X70 220X70 220X70 240X70 120X70 140X70 170X70 190X70 220X70 220X70 240X70 120X70 140X70 170X70 190X70 220X70 240X70 240X70 - FLOOR JOIST MAX SPAN 1800 2100 2400 2700 3000 3300 3600 FLOOR JOIST @ 450MM CENTRES (F7) SPAN TYP USE F7 SINGLE 120X40 CONT 100X50 SINGLE 125X50 CONT 125X40 SINGLE 150X40 CONT 125X50 SINGLE 150X50 CONT 150X40 SINGLE 175X40 CONT 150X40 SINGLE 175X50 CONT 150X50 SINGLE 175X50 CONT 150X50 STUDS-EXTERNAL WALLS DESIGN WINDSPEED OF 74.5m/s STUD SPACING 450 600 STUD HEIGHTUSE F7 2400 100X50 2700 100X75 3000 100X75 2400 100X75 2700 100X75 3000 100X100 INTERNAL LOAD BEARING WALL STUD SPACING 450 600 STUD HEIGHTUSE F7 2400 75X50 2700 100X40 3000 100X50 3300 100X75 3600 100X75 3900 100X75 4200 2/100X50 2400 75X40 2700 100X40 3000 100X50 3300 100X50 3600 100X75 3900 2/100X50 4200 - TOP PLATE BUILDING WIDTH RAFTER SPACING USE 7500 900 50X100 9000 900 50X100 BOTTOM PLATE BUILDING WIDTH RAFTER SPACING USE 7500 900 50X100 9000 900 50X100 RAFTER ASPECT RATIO ROOF h/d PITCH DEG 0.25 15,20,25 0.5 20,25 1 25 DESIGN WIND SPEED 74.5m/s RAFTER SPACING RAFTER SPAN USE F7 900 3000 175X50 3600 200X50 4200 225X50 4800 250X50 5400 275X50 1200 3000 200X50 3600 225X50 4200 275X50 4800 300X50 5400 1500 3000 225X50 3600 275X50 4200 300X50 4800 5400 - PURLINS RAFTER SPACING PURLIN SPACING USE F7 750 750 50X50 900 50X50 1200 50X75 900 750 50X75 900 75X50 1200 75X50 VERANDAH POST POST HEIGHT 2400 2700 AREA OF ROOF 5 10 20 5 10 20 USE F7 100X100 100X100 100X100 100X100 100X100 100X100 STEEL WASHERS BOLT TYPE M10 M12 M16 M20 SQUARE 40X2.5 50X3 57X4 65X5 ROUND 45X2.5 55X3 65X4 75X5