Smartspan® Technical Information

Profile

Material Specifications

Material Specifications
Material Properties Finish 0.42 BMT 0.48 BMT
Total Coated Thickness (TCT) mm Zinc/alum 0.47 0.53
Colour 0.50 0.56
Mass (kg / linear metre) Zinc/alum 3.26 3.70
Colour 3.32 3.76
Mass (kg / square metre) Zinc/alum 4.66 5.28
Colour 4.74 5.37
Yield (square metre / tonne) Zinc/alum 214.6 189.4
Colour 211.0 186.2
Tensile Strength (MPa) Zinc/alum & Colour 550 550
Width Coverage (mm) Zinc/alum & Colour 700 700
Sheet Tolerances (mm) Length & Width ±5 ±2 ±5 ±2
Minimum Roof Pitch Zinc/alum & Colour

Spans

Spans are determined by wind speeds for non-cyclonic areas. For domestic applications, the pressures and spans are based on a maximum: eaves height of six metres, roof pitch of 35 degrees and total roof height of 8.5 metres. For commercial and industrial applications, tables are based on a maximum overall height of ten metres and a 500 year design return period.

Roofing calculations are based on Cpe=-0.9 and Cpi=0.2, walling is based on Cpe=-0.65 and Cpi=0.2. A local pressure factor, Kl=2.0 has been used for all roofing and walling spans for both strength and serviceability limit states. Roof spans allow for loads incidental to maintenance.

All pressures have been determined assuming the wind loading in any direction is not affected by topography. The following shielding factors have been used for each of the terrain categories: Category 3 = 0.85, Category 2.5 = 0.95, and Category 2 = 1.

The carport and verandah spans only apply to structures not enclosed by peripheral walls. Spans are based on Cpn=-0.9 and Kl=1.5 applied over the entire span, and are suitable for all span types. Loads on supporting purlins may limit these spans.

Stratco can provide additional engineering advice if any design parameters vary from those above.


Wind Load Conversion

For domestic applications use the appropriate wind classification for the area. To read the span tables for commercial and industrial applications, select the region and category for the area, then convert it to the correct classification using table below.

Wind Load Conversion
Wind Classification (Domestic) Region & Category (Commercial / Industrial)
N1 (W28) Reg A, Cat 3
N2 (W33) Reg A, Cat 2.5 - Reg B, Cat 3
N3 (W41) Reg A, Cat 2 - Reg B, Cat 2.5
N4 (W50) Reg B, Cat 2

Maximum Recommended Spans

Maximum Recommended Spans (mm)
Span Type Roofing (BMT) Walling (BMT)
0.42 mm 0.48 mm 0.42 mm 0.48 mm
Single Span 1350 2000 2550 2600
End Span 1800 2300 3200 3300
Internal Span 2400 3000 3500 3600
Un-stiffened Overhang 200 250 200 250
Stiffened Overhang 500 600 500 600

Roofing spans are limited, based on typical maintenance foot traffic. Walling spans are based on N1 (W28) wind loading. All spans are based on four fasteners per sheet, per support. The values are for use with steel supports with a minimum thickness of 0.75mm, G550.

Domestic Carport / Verandah Spans

Domestic Carport / Verandah Spans (mm)
Wind Classification Base Metal Thickness
0.42 mm 0.48 mm
N1 (W28) 2500 2700
N2 (W33) 2500 2700
N3 (W41) 2100 2300
N4 (W50) 1800 2000

The values are for use with steel supports with a minimum thickness of 0.75mm, G550.

Spans

Spans (mm)
BMT Application Span Type Three Fasteners Four Fasteners
N1 (W28) N2 (W33) N3 (W41) N4 (W50) N1 (W28) N2 (W33) N3 (W41) N4 (W50)
0.42 mm Roofing Single 1350 1350 1350 - 1350 1350 1350 1350
End 1800 1800 1700 - 1800 1800 1800 1500
Internal 2400 2000 1800 - 2400 2400 2250 1600
Walling Single 2300 1950 1750 1500 2550 2050 1900 1750
End 3000 2300 1950 1550 3200 2650 2150 1800
Internal 3300 2500 2000 1750 3500 3100 2750 1950
0.48 mm Roofing Single 2000 1850 1500 - 2000 2000 1800 1700
End 2300 2100 1800 - 2300 2300 2100 1750
Internal 3000 2350 2000 - 3000 2850 2350 2000
Walling Single 2350 2100 1850 1750 2600 2250 2050 1950
End 3000 2350 2100 1850 3300 2700 2300 2150
Internal 3400 2950 2350 1950 3600 3300 2850 2400

The values are for use with steel supports with a minimum thickness of 0.75mm, G550.

Wind Capacities

Wind Capacities (kPa)
BMT Span Type Limit State Span (mm) Three Fasteners Span (mm) Four Fasteners
1200 1500 1800 2100 2400 2700 3000 3300 3600 3900 1200 1500 1800 2100 2400 2700 3000 3300 3600 3900
0.42 mm Single Serviceability 2.09 1.64 1.18 0.73 0.58 0.43 - - - - 2.73 2.12 1.52 0.91 0.71 0.51 - - - -
Strength 4.74 4.30 3.87 3.43 3.07 2.71 - - - - 6.06 5.34 4.62 3.90 3.50 3.11 - - - -
End Serviceability 2.41 1.97 1.52 1.08 0.93 0.79 0.64 0.49 0.35 - 3.36 2.67 1.97 1.27 1.09 0.91 0.73 0.55 0.36 -
Strength 3.95 3.44 2.92 2.40 2.16 1.92 1.67 1.43 1.19 - 5.27 4.51 3.76 3.00 2.74 2.48 2.22 1.96 1.70 -
Internal Serviceability 2.82 2.24 1.67 1.09 0.98 0.87 0.75 0.64 0.53 - 4.27 3.44 2.61 1.77 1.52 1.27 1.03 0.78 0.53 -
Strength 4.96 4.09 3.22 2.35 2.13 1.91 1.69 1.47 1.25 - 5.55 4.78 4.00 3.23 2.95 2.67 2.40 2.12 1.84 -
0.48 mm Single Serviceability - 1.70 1.32 0.94 0.55 0.47 0.38 0.30 - - - 2.20 1.70 1.20 0.70 0.57 0.43 0.30 - -
Strength - 4.75 4.21 3.67 3.13 2.74 2.34 1.95 - - - 6.10 5.53 4.95 4.38 3.86 3.33 2.81 - -
End Serviceability - 2.05 1.67 1.29 0.91 0.77 0.63 0.48 0.34 0.20 - 2.91 2.31 1.72 1.12 0.95 0.78 0.61 0.44 0.27
Strength - 4.01 3.48 2.96 2.44 2.13 1.83 1.52 1.22 0.91 - 5.10 4.44 3.78 3.12 2.78 2.45 2.12 1.79 1.46
Internal Serviceability - 2.30 1.94 1.57 1.21 1.06 0.91 0.77 0.62 0.47 - 3.57 2.90 2.22 1.55 1.34 1.14 0.93 0.73 0.53
Strength - 4.33 3.72 3.11 2.49 2.18 1.87 1.56 1.24 0.93 - 5.67 4.96 4.26 3.55 3.15 2.74 2.33 1.92 1.51

The values are for use with steel supports with a minimum thickness of 0.75mm, G550.

Water Carrying Capacity

Maximum Roof Run For Drainage (m)
Roof Slope Peak Rainfall Intensity (mm / hr)
150 180 200 250 300 350 400 450
86 72 64 51 43 37 32 28
137 114 102 82 68 58 51 45
7.5° 168 140 126 100 84 72 63 56
10° 194 162 145 116 97 83 73 64
15° 239 199 179 143 119 102 89 79
22° 294 245 220 176 147 126 110 98

The peak rainfall intensities shown represent a 100 year average recurrence interval (ARI) for a five minute rainfall duration. If roof penetrations exist, the total roof run will generally be greater than the distance from ridge to eaves at the location the penetration interferes with the runoff. Contact Stratco if further advice is required.