New Zealand Steel's colour coating line produces COLORSTEEL® for roofing and cladding applications. Metal coated coils are delivered to the colour coating mill for further processing where they first undergo a pre-treatment before painting begins. Once the pre-treatment has been applied a prime coating is applied to both sides of the strip and baked on in the prime oven. This process is then repeated with the application of the finish coating. The strip is then branded and wound, ready for delivery to customers.