Description

The most common building materials made from metals are produced from carbon steel, stainless steel, zinc, galvanized steel, aluminium and its alloys, lead and copper and its alloys.

For each type of metal, the specification that describes the numerous subclasses of each metal type can have a significant influence over durability expectations. These specifications are discussed in this bulletin for the most common metals and subclasses. This includes those specifically noted within Acceptable Solutions to the Building Code such as E2/AS1, AS/NZS 2312:2014 Guide to the protection of structural steel against atmospheric corrosion by the use of protective coatings and NZS 3604:2011 Timber-framed buildings.

The corrosivity category is a technical characteristic that provides a basis for the selection of materials and protective measures in atmospheric environments subject to the demands of the specific application, particularly with regard to service life. The corrosivity categories are defined by the first-year corrosion rates of standard metal specimens.