Structure

The information in this section explains the various factors used in calculating design loads and in resisting those loads to ensure roofs are structurally sound and meet the objectives of NZBC B1 Structure.

The designer must be familiar with the performance requirements of the New Zealand Building Code (NZBC). Loads can be calculated in accordance with the appropriate standard and maximum spans and fastening patterns specified according to manufacturers’ literature, or for designs to NZS3604:

• G550 Steel Cladding Fastening Pattern Tables, and
• Aluminium Fastening Pattern Tables

For SED projects to AS/NZS 1170, designers can use:

• Steel Cladding Wind Load Span Graphs, and  
• Aluminium Cladding Wind Load Span Graphs.  

It is the responsibility of the roofing contractor to install roof cladding according to the design and raise any concerns with the designer before commencement.