Adverse Conditions
Stramit Longspan® cladding will give excellent durability in almost all locations. It is however important to choose the correct coating for each application environment. The table below shows the suitability of coating types for different exposure conditions.
suitability of coating type
site exposure condition
benign
moderate
severe
very severe
Zincalume AZ150
?
?
Galvanised Z450
?
Colorbond XRW
?
Colorbond XSE
N/A
N/A
?
? Question marks indicate conditions where durability may be diminished, depending on the particular application.
The approximate site exposure conditions in the table above are defined below.
Distance of site from
site exposure conditions
rough
active surf
calm, still
salt water
industrial
emission
fossil fuel
combustion
benign
1000m +
100m +
500m +
500m +
moderate
400m-1000m
0-100m
250m-500m
250m-500m
severe
100m-400m
N/A
100m-250m
100m-250m
very severe
0-100m
N/A
0-100m
0-100m
Spans
The spans shown below take account of 'normal' foot traffic and wind resistance including local pressure zone effects.
Pressures are based on AS4055 or AS1170.2 section 2. Where the two standards differ, the worst case has been taken for each classification.
Data should only be used for buildings 7m or less in height, 1000m2 or less in area and unaffected by land topography.
Maximum Span Chart (mm)
Fasteners per sheet
at each support
Roofs
Overhangs
bmt (mm)
pressure (kPa)
internal (end) span combination
free edge
stiffened edge
serviceability
strength
double span
equal spans
N1 or Region A (sheltered suburban)
0.42
3 screws
4 screws
0.76
0.76
1.35
1.35
1750
1750
1750
1750
2100 (1750)
2100 (1750)
200
200
500
500
0.48
3 screws
4 screws
0.76
0.76
1.35
1.35
2250
2250
2250
2250
2700 (2250)
2700 (2250)
250
250
500
500
N2 or Region B (sheltered suburban) and Region A (exposed suburban)
0.42
3 screws
4 screws
0.78
0.78
1.94
1.94
1750
1750
1750
1750
2100 (1750)
2100 (1750)
150
200
450
500
0.48
3 screws
4 screws
0.78
0.78
1.94
1.94
2250
2250
2250
2250
2700 (2250)
2700 (2250)
200
250
500
500
N3 or Region A (rural) and Region B (exposed suburban)
0.42
3 screws
4 screws
5 screws
1.18
1.18
1.18
2.96
2.96
2.96
1600
1750
1750
1600
1750
1750
1900 (1550)
2100 (1750)
2100 (1750)
100
150
150
400
450
450
0.48
3 screws
4 screws
5 screws
1.18
1.18
1.18
2.96
2.96
2.96
2050
2250
2250
2050
2250
2250
2350 (1950)
2650 (2200)
2700 (2250)
150
200
250
450
500
500
Walls
N1 or Region A (sheltered suburban)
0.42
3 screws
4 screws
0.61
0.61
1.04
1.04
2700
3000
2700
3000
3000 (3000)
3000 (2500)
0.48
3 screws
4 screws
0.61
0.61
1.04
1.04
3000
3000
3000
3000
3000 (2500)
3000 (2500)
N2 or Region B (sheltered suburban) and Region A (exposed suburban)
0.42
3 screws
4 screws
0.61
0.61
1.49
1.49
2700
3000
2700
3000
3000 (2500)
3000 (2500)
0.48
3 screws
4 screws
0.61
0.61
1.49
1.49
3000
3000
3000
3000
3000 (2500)
3000 (2500)
N3 or Region A (rural) and Region B (exposed suburban)
0.42
3 screws
4 screws
5 screws
0.92
0.92
0.92
2.25
2.25
2.25
2050
2500
2550
2050
2500
2500
2350 (1950)
2650 (2200)
3000 (2500)
0.48
3 screws
4 screws
5 screws
0.92
0.92
0.92
2.25
2.25
2.25
2500
2900
2850
2500
2900
2900
2800 (2300)
3000 (2500)
3000 (2500)
Internal spans must have both end spans 20% shorter. Values are only valid for use with steel members of 0.75mm or thicker.
For more specific applications Stramit Longspan® cladding must be designed to the pressure and foot traffic limitations below.
Pressures
Serviceability Limit State Capacity
thickness
bmt (mm)
fasteners
per sheet
span type
(kPa) at the spans (mm) shown
600
900
1200
1500
1800
2100
2400
2700
3000
0.42
3
internal
equal
double
1.66
1.58
1.58
1.66
1.58
1.58
1.53
1.42
1.42
1.39
1.25
1.25
1.25
1.07
1.07
1.10
0.90
0.90
0.95
0.75
0.75
0.82
0.62
0.62
0.70
0.54
0.54
4
internal
equal
double
5.58
4.93
4.93
5.58
4.93
4.93
4.52
3.78
3.78
3.60
2.82
2.82
2.82
2.05
2.05
2.16
1.45
1.45
1.63
1.03
1.03
1.22
0.77
0.77
0.93
0.66
0.66
5
internal
equal
double
5.58
4.93
4.33
5.58
4.93
4.33
4.52
3.78
3.60
3.60
2.82
2.87
2.82
2.05
2.19
2.16
1.45
1.59
1.63
1.03
1.11
1.22
0.77
0.78
0.93
0.66
0.65
0.48
3
internal
equal
double
2.66
2.39
2.39
2.66
2.39
2.39
2.24
1.98
1.98
1.92
1.69
1.69
1.69
1.49
1.49
1.52
1.34
1.34
1.39
1.18
1.18
1.26
0.99
0.99
1.12
0.71
0.71
4
internal
equal
double
8.67
7.17
7.17
8.67
7.17
7.17
6.31
4.88
4.88
4.57
3.35
3.35
3.35
2.42
2.42
2.54
1.88
1.88
2.03
1.55
1.55
1.70
1.25
1.25
1.46
0.77
0.77
5
internal
equal
double
8.67
7.17
4.97
8.67
7.17
4.97
6.31
4.88
3.94
4.57
3.35
3.09
3.35
2.42
2.39
2.54
1.88
1.84
2.03
1.55
1.40
1.70
1.25
1.05
1.46
0.77
0.79
Strength Limit State Capacity (Non-Cyclonic)
thickness
bmt (mm)
fasteners
per sheet
span type
(kPa) at the spans (mm) shown
600
900
1200
1500
1800
2100
2400
2700
3000
0.42
3
internal
equal
double
7.35
6.98
6.98
7.35
6.98
6.98
5.82
5.24
5.24
4.56
3.89
3.89
3.56
2.90
2.90
2.78
2.22
2.22
2.21
1.79
1.79
1.80
1.56
1.56
1.54
1.48
1.48
4
internal
equal
double
8.57
8.63
8.63
8.57
8.63
8.63
6.80
6.49
6.49
5.35
4.85
4.85
4.19
3.65
3.65
3.30
2.83
2.83
2.64
2.35
2.35
2.20
2.15
2.15
1.94
2.17
2.17
5
internal
equal
double
9.39
9.41
9.41
9.39
9.41
9.41
8.35
8.11
8.11
7.36
6.92
6.92
6.44
5.85
5.85
5.60
4.93
4.93
4.86
4.21
4.21
4.23
3.71
3.71
3.74
3.46
3.46
0.48
3
internal
equal
double
8.09
7.83
7.83
8.09
7.83
7.83
6.62
6.13
6.13
5.39
4.77
4.77
4.37
3.72
3.72
3.55
2.94
2.94
2.90
2.39
2.39
2.41
2.03
2.03
2.06
1.83
1.83
4
internal
equal
double
9.63
9.58
9.58
9.63
9.58
9.58
7.50
7.14
7.14
5.88
5.43
5.43
4.69
4.30
4.30
3.85
3.61
3.61
3.28
3.20
3.20
2.91
2.92
2.92
2.67
2.63
2.63
5
internal
equal
double
11.18
10.77
10.77
11.18
10.77
10.77
9.35
8.76
8.76
7.91
7.29
7.29
6.80
6.24
6.24
5.96
5.50
5.55
5.33
4.97
4.97
4.86
4.53
4.53
4.49
4.08
4.08
Tables are based on testing to AS1562 and AS4040 parts 0, 2 and 3. Internal spans must have bothe end spans 20% shorter.
Values only valid for use with steel support members of 0.75mm or thicker.
Foot Traffic
Foot traffic limits for Stramit Longspan® cladding are shown for three alternate foot traffic categories.
These are:
High maintenance - for applications with repeated maintenance, particularly where personnel may be unfamiliar with correct procedures for walking on metal roofs.
Normal - based on traditional expectations, with moderate maintenance foot traffic using designed foot paths.
Controlled - spans that conform to AS1562 but require minimal careful foot traffic only on the designated foot path. Suggested for use only where occasional aesthetic imperfections from foot traffic are acceptable.
Foot Traffic Limited Spans (mm)
Thickness
bmt
span type
foot traffic limits
heavy
normal
controlled
0.42
internal
-
2100
2400
equal
-
1750
1800
double
-
1750
1800
0.48
internal
800
2700
3000
equal
600
2250
2250
double
600
2250
2250
Tables are based on tests to AS1562 and AS4040 parts 0 and 1.
Photographs
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