Zinc Aluminium (AZ) roof sheeting material has made it more affordable for metal roofing applications along the coast as opposed to Aluminium and Stainless Steel roof sheeting material. This has led it to be one of the preferred roof sheeting material along the coast.
As we’ve learned about our environments and the various factors that impact our fastener performance, we have taken significant steps over the years to overcome these challenges.
Class 3 and Class 4 coated fasteners are the recommended class of fastener to be used with AZ150 and AZ200 grades respectively. As AZ material was introduced into the South African market, with time we learned that although AZ200 material performs well in close proximity to marine environments, this did not mean the Class 4 fastener was suited for the same environment.
After conducting an independent assessment within an area that was common to this issue it was found that although the fasteners are Class 4 it was found to be in a C5-M, Class 5 environment generally located 0-500m from a severe marine environment. As relates to fasteners these C5-M environments call for the use of stainless steel fasteners. Stainless Steel fasteners, although recommended for the environment, is not compatible with AZ material.
These findings presented a challenge to our customers and the broader roofing and cladding community. In partnership with our manufacturer, Engineering-Edge, we arrived at the PROTAPP Fastener. This fastener has a Class 4 coated shank with a non-metallic head which is not susceptible to corrosion, thus presenting an alternative solution to this dilemma.
The PROTAPP Fastener is highly recommended for Class 5 environments with AZ200 steel roofing. It also negates the need for an insulating sleeve between the PROTAPP Fastener and the sheeting.