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.
Standing Seam or Tray roofing is similar to trough section in that it is secret fixed, but it consists of just a single pan per sheet, compared to the two or three pans of a trough section.
The profiles and fixing methods for tray roofing date back to traditional methods used to hand-fabricate metal roofs, predominantly in Europe and often from non-ferrous metal, prior to the development of roll forming technology. A by-product of this heritage is that, in addition to the secret clips fastening the main roof, flashings should also be installed on clips with minimal use of exposed rivets and fasteners.
In Europe, the installation of tray roofing is done by Spenglers, who serve a 4-year apprenticeship. We do not have the same qualification in NZ, but installers of tray roofing must have specific training and experience in the product if they are to achieve the expected high standard of workmanship