Prior to 1970’s many steel roofs were large galvanised. Then a Chicago-based company, Lithostrip Corporation and Pre Finish Metals, discovered a way to successfully bond paint to a galvanised base.
John Lysaght brought the technology into Australia and invested much time and effort getting the process right. This resulted in COLORBOND® steel being rolled out of a Wollongong manufacturing facility for the first time in 1966.
BHP Steel (now BlueScope Steel) bought half of Lysaght’s company in 1969, and by 1988 John Lysaght (Australia) was a wholly owned subsidiary of BHP. Today BlueScope Steel are also known for selling ZINCALUME® steel which was developed in 1976 and possessed a higher level of corrosion resistance.
Sometime later, BlueScope developed AQUAPLATE® steel specifically for the storage of drinking water. This steel is made from a base comprised of galvanised steel that is laminated with food-grade polymer film on the inside.
While AQUAPLATE® steel is well known in its pre-painted COLORBOND® steel form, it is actually available in painted and unpainted forms:
- painted or laminated exterior – ZINCALUME® steel (ZINCFORM® G300S) hot-dip coated in 275g/m2 zinc (Z275)
- unpainted exterior – ZINCALUME® steel (G300S) hot-dip coated in 450g/m2 zinc (Z450).
What makes AQUAPLATE® steel specifically AQUAPLATE® is its interior laminated coating of food-grade polyethylene. This is a very thin layer a poly applied during fabrication being only 0.2mm thick (about one quarter the thickness of a credit card).