Widespan Sheeting

 
 
 
Widespan is a roofing and cladding profile designed to provide an economic alternative to deeper Box Rib profiles without losing the aesthetic appeal of a square fluted profile. The trapezoidal Widespan profile offers greater spans and lower roof slopes than Corrugated sheeting but provides the same covering width. Widespan can be factory cranked, curved and bullnosed to various radii depending on customer's requirements.
 
 
 
 
 
 

Structural Guidelines

 
 
 
Widespan roof sheets are available in a wide range of materials displaying various structural properties. It should be noted that the load span characteristics are only to be used as a broad guideline as purlin spacing is also dependant on other factors such as the prevailing winds in a certain area, snow during winter periods, the presence of dust and other particles in industrial areas, the type of structure that is being erected etc.. We therefore recommend that an engineer is consulted to determine the purlin spacing for a specific application. The structural properties of the various material options can be summarised as follows.
 
Recommended Maximum Purlin Spacing (meter)
Thickness
0.47 mm
0.53 mm
0.40 mm
0.50 mm
0.58 mm
0.80 mm
Steel Grade
G550
G550
ISQ300
ISQ550
ISQ300
ISQ230
Roof - single span
1.35
1.40
0.90
1.35
1.40
1.60
Roof - double span
1.55
1.65
1.19
1.55
1.65
1.90
Cantilever - roof
0.40
0.45
0.20
0.40
0.45
0.55
Wall - single span
1.80
1.95
1.25
1.80
1.95
2.20
Wall - double span
2.20
2.35
1.70
2.20
2.35
2.75
Cantilever - wall
0.90
1.00
0.50
0.90
1.00
1.15
Weight per meter
3.194 kg
3.833 kg
2.897 kg
3.615 kg
4.197 kg
5.798 kg
Weight per sq metre
4.191 kg
5.030 kg
3.801 kg
4.744 kg
5.507 kg
7.608 kg
Coating type
Zincalume
Zincalume
Galvanised
Galvanised
Galvanised
Glavanised
Coating weight
AZ 150
AZ 150
Z 160
Z 275
Z 275
Z 275
Paint system
Colorbond
Colorbond
N/A
Chromadek
Chromadek
Chromadek
Thickness tolerance
+/- 0.03
+/- 0.04
+/- 0.02
+/- 0.02
+/- 0.03
+/- 0.04
 
 
Approximate life span (years)
Thickness
0.47 mm
0.53 mm
0.40 mm
0.50 mm
0.58 mm
0.80 mm
Steel Grade
G550
G550
ISQ300
ISQ550
ISQ300
ISQ230
Rural area
>30
>30
>10
>20
>20
>20
Industrial / Marine
>20
>20
5 - 10
10 - 20
10 - 20
10 - 20
Severe marine
10 - 20
10 - 20
1 - 5
3 - 10
3 - 10
3 - 10
 
 
 
 
 

Available Dimensions

 
 
 
Widespan sheeting is available in standard lengths of 1.5 to 14 metres although a length up to 20 metres is available on request. The permissible length tolerance for the standard length range will be -0 +5 mm. Sheets outside these parameters are available on request and might be subject to special pricing arrangements. The maximum height which can be transported is 4.3 metres. This factor should be taken into account when bullnoses and curves are designed.
 
 
 
 
 

Roof Pitch

 
 
 
When using Widespan, the recommended minimum pitch for roof slopes in excess of 30 m is 10.0º and for slopes less than 30 m is 7.5º. When Widespan roof sheets are end lapped the roof pitch should be taken into account. The minimum end laps for roofs pitches in excess of 15º is 150 mm and for other roofs a minimum of 250 mm is recommended. End laps for side sheeting should be at least 100 mm. It is recommended that end and side laps on low pitched roofs are sealed to ensure watertightness.
 
 
 
 
 

Specification
 
 
 
Clotan Steel Widespan (with/without) integral stiffening rib (coating) steel sheeting and accessories with (Chromadek/Colorbond) finish on one side and protective primer coating on the reverse side fixed to (timber/steel) purlins or rails with a (*refer to table) spacing. All sheeting is to be clearly marked on the reverse side at one-metre intervals, indicating thickness, material quality and coating thickness.
 
Thickness & Material Quality
Coating
Available Paint System
0.40 mm - ISQ300
Z160 Galvanised
 
0.50 mm - ISQ550
Z275 Galvanised
 
0.58 mm - ISQ300
Z275 Galvanised
 
0.80 mm - ISQ230
Z275 Galvanised
 
 
0.50 mm - ISQ550
Z275 Galvanised
Chromadek
0.58 - ISQ300
Z275 Galvanised
Chromadek
0.80 - ISQ230
Z275 Galvanised
Chromadek
 
0.47 mm - G550
AZ 150 Zincalume
 
0.53 mm - G550
AZ 150 Zincalume
Colorbord

 
 
 
 

Installation Procedure

 
 
 
The required number of Widespan sheets can be calculated as follows:
 
Number of sheets = Length of building + gable end overhangs - 50 mm
 
0.762 m (Cover width of sheet) roof sheets must be laid with one corrugation side lap with the narrow flute uppermost and shall be fixed through the crests of alternate flutes to purlins using 57 mm Top Speed or Tex screws into steel purlins and 90 mm Tex or Top speed screws in the case of timber roofs, all fasteners shall incorporate 19 mm dia bonded washers.

For vertical wall cladding (side cladding) it is recommended that the broad fluted are fixed externally with the main and side lap fasteners in the web of the flutes. Side cladding can be fixed using 25 mm Tex or Top speed screws, all fasteners shall incorporate 19 mm dia bonded washers.

In order to qualify for a guarantee on Zincalume and Colorbond sheets the following fasteners supplied by Buildex Industries should be used: Metaltex  Climaseal 3 for steel purlins and Timbertex Zacs 4 for timber purlins. The use of these fasteners will dramatically increase the lifespan of the roof sheeting as corrosion caused by fasteners is avoided.
 
 
 
 
 
   
 
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