Fastener Design
Super Six should be screw fixed to either timber or steel purlins. The use of the appropriate length of 12g or 14g screw
will ensure failure by screw pull out will not occur under loads within the scope of the Limit State Load / Roofing Span
Capacity Chart.
Natural Lighting Systems Load / Span / Fastener Design
| Profile | Gauge (mm) | Nominal Sheet Weight (kg)/m² | Max. Internal Span (mm)* - ULS 1.0kPa** | Max. Internal Span (mm)* - ULS 1.5kPa** | Max. Internal Span (mm)* - ULS 2.0kPa** | End Span - Fasteners/sheet/purlin | Internal Span - Fasteners/sheet/purlin |
| Super Six (min pitch 3°) | 1.1 | 1.8 | 1800 | 1400 | 1200 | 4 | 4 |
| Super Six (min pitch 3°) | 1.4 | 2.4 | 2000 | 1600 | 1400 | 4 | 4 |
| Super Six (min pitch 3°) | 1.7 | 3.0 | 2300 | 1800 | 1600 | 4 | 4 |
Note:
*End Span = 0.7 x Internal Span
**ULS = Ultimate Limit State Capacity
- The spans given are for internal purlin spacings.
- The tabulated data does not apply to single spans. Single spans must be reduced to 0.5 x internal span
- These spans apply where the Natural Lighting sheets are installed with both side edges supported by an adjacent metal roof.
- For continuous coverage of two or more Natural Lighting sheets we recommend reducing the spans 0.9 x internal spans.
| Purlin Type | Roofing Rib Screw Length* (mm) | Roofing Rib Designation | Wall Cladding Screw Length* (mm) | Wall Cladding Designation |
| Timber | 75 | T17 - 14 - 10 x 75 | 50 | Roofzip M6x50mm |
| Steel | 65 | Tek - 12 - 14 x 68 Tek - 14 - 10 x 65 |
20 | TEK - 12 - 14 x 20 |
* If sarking or insulation is used over the purlins, screw length will need to be increased.
For screw size range and fastener / washer assembly refer Section 2.2.3.1.
The Limit State Load / Span Capacity Chart is based on 4 screw fasteners/sheet/purlin using load spreading washers that
are either profiled metal washers and 36mm EPDM seals, or 32mm Weatherlok washers.
Long spans may require the specification and use of side lap stitching screws – see Section 2.3.2C Installation
Information: Layout and Fastening.
Design Example
Restricted access roof, Duraclad Super Six has a maximum end span of 1000mm and a maximum internal span of
1200mm. The following distributed load capacities apply.
| 4 fasteners/sheet | |
| End Span | 1000mm |
| Ultimate | 4.5 kPa |
| Internal Span | 1200mm |
| Ultimate | 4.5kPa |
