AS 3566.2 WITHDRAWN BY STANDARDS AUSTRALIA BUT STILL CITED IN E2/AS1?
AS 3566.2 Self Drilling Screws for the Building and Construction Industries - Corrosion Resistance Requirements, is cited in NZBC E2/AS1 (and Simple House), but has been withdrawn in Australia by Standards Australia.
For the most part references to AS 3566.2 call up the Class durability rating of screws, which are typically Class 3 for hidden/protected situations and Class 4 for exposed situations. This is reflected in the Acceptable Solutions, with NZBC E2/AS1 referring to it for profiled metal roofing and cladding fixings and for general situation fixings in NZBC E2/AS1, Table 20. The Simple House Acceptable Solution similarly refers to it for profiled metal roofing but also for brick veneer tie fixings (although E2/AS1 brick veneer does not).
As the Class 3 and 4 screws are well established in the industry and with no replacement Standard yet, we expect that the same Class ratings will be around for quite some time. So until the Acceptable Solutions change their references or the industry changes, Masterspec will continue to reference AS 3566.2, as the Class ratings are derived from it.
There is a small rider to this. In recent times a higher performance Class 5 screw has been developed but has not made it into the Standard. We are not sure, but this maybe one of the reasons why the Standard was withdrawn, perhaps it may appear in a new Standard?
The new Class 5 is favoured by roofing manufacturers and suppliers for more severe exposure situations. Although, not strictly an Acceptable Solution, it in fact exceeds the requirements and seems to becoming an accepted alternative. Masterspec already includes Class 5 in most of the profiled metal roofing and cladding sections as a recommended option for more severe exposures.