The NZ Metal Roof and Wall Cladding Code of Practice is a comprehensive design & installation guide, and a recognised related document for Acceptable Solution E2/AS1 of the NZ Building Code.
It must not be assumed that it is safe or permissible to stand on any roof structure or roof cladding.
The manufacturer of the roof sheeting must provide technical literature stating the point load limitations of the profile. The information must indicate the positions on the sheet where persons may safely walk or stand without causing damage or, alternatively, indicate the necessity to provide temporary walkways.
When access to the roof is necessary after construction, workers must walk in the pan of trough-type profiles or within 300 mm of the purlin fastenings.
If ribs are close together so that a workman cannot place his foot in the pan, his weight must be spread evenly over at least two ribs when walking up the roof, and when walking across the roof he should step close to, but not on, the fastener.
Translucent sheeting must not be walked on unless it is designed specifically for that purpose.