COP v3.0:introduction

View Whole Section for Introduction

The NZ Metal Roof and Wall Cladding Code of Practice (COP) is published by NZ Metal Roofing Manufacturers Inc. (MRM), to provide:

  • acceptable trade practice for the fixing of metal roof and wall cladding and accessories.
  • prescriptive detailing for designers and sets a benchmark for the standard of detailing and workmanship required over and above that required to comply with the NZBC.

The COP does not describe or dismiss alternative methods, which may need specific acceptance by the Building Consent Authorities.

It is published in accordance with current technology, materials, and building codes. The COP will be periodically updated to reflect changes in legislation and standards or improvements in technology and available materials.

The most current Code of Practice is available on the MRM website,, as Code of Practice Online (MRM COP Version 3).

The most recent Update to the COP was on 1 March 2020.

This update contains only minor revisions, mostly concerning grammar and punctuation fixes.

Editing and rearrangement for clarity

  • Corrected "upstand angles" of valleys to 90°, removed "Upstand Angles" from Internal Valley Angle Table.
  • Replaced Comparison of 10-Minute Published Intensity with 1-Minute and 2-Minute Intensities-chart with a simplified chart only showing comparison for 10-year and 50-year ARI.

See 19.1 2020 – March for details of the changes in this Update.