Zinc And Storm Water Run-Off

Zinc And Storm Water Run-Off

Zinc and storm water run-off
Article supplied courtesy of Jenny Bain, Rooflink

The Auckland Regional Council (ARC) has done an about turn on its earlier claim that zinc-based roofs were responsible for increased levels of zinc in harbour sediments. The ARC now acknowledges that the use of COLORSTEEL® prepainted steel and ZINCALUME® steel roofing products have contributed to falling zinc levels noted in the harbours and that this trend will be likely to continue.
The council has added that run off from unpainted ZINCALUME®roofs should also be treated no differently to painted ones – marking a major turning point in the debate over zinc run-off. Unfortunately the fallout from the earlier ruling by the ARC means that many regional councils and territorial authorities followed the ARC’s lead when it circulated its now defunct document Policy Implications from roof run-off study” and have been determining policies based on what has turned out to be an incorrect ruling.
One such council is Environment Canterbury (ECAN) whose  decisions on the use of unpainted ZINCALUME® have been influenced by those previously imposed by ARC. New Zealand Steel has now requested ECAN to review its current storm water discharge consent conditions.
Any RANZ members who experience issues with resource consent for a metal roof – either with material selection or water run-off should advise the MRM’s Sustainability Sub-committee who will ensure that councils and designers are correctly informed about zinc run-off.

Pacific Coilcoaters New Website

Pacific Coilcoaters has fully update its website. The site carries a range of material to assist the industry, including brochures, case studies and advice, technical bulletins, and the ability to inquire on-line for a pre-ap  proved warranty for a specific project (see Please visit the site at .

CPD Provider to BOINZ
Pacific Coilcoaters is pleased to have been appointed a CPD provider to BOINZ. This enables us to present detailed information on correct product, designs and environmental issues to consider, and to answer any general questions and concerns that BOINZ members may have. The presentations are conducted locally (at Council offices normally) to maximise the ability of members to attend, and to allow for ‘localised’ issues to be addressed specifically.
If you are interested in having one of these sessions contact our Architectural Manager, Rob Armstrong, on, or 0800-ARXZRX, or 021-927314.

ZAM material
PCC recently started providing the ZAM® substrate to the New Zealand market. ZAM® is a steel substrate with a zinc rich metallic coating that incorporates magnesium. This metallic coating provides superior corrosion protection, especially on the cut edges, compared to other materials.
The ZAM® substrate is being used under our standard Water borne and PVF2 paint systems, and is supplied as ColorCote® ZM8™ (water borne) and ZMX™ (PVF2 paint). The products are designed to provide improved corrosion resistance for products such as rainwater products and spouting, and to improve corrosion performance in severe marine and severe industrial conditions (note however they do not replace Aluminium products in very severe marine and geothermal areas).
For more information, visit or contact Rob Armstrong (our Architectural Manager) on 021- 927313 or

Latest Developments:
Low gloss PVF2 paint
Pacific Coilcoaters has developed a low gloss (10% nominal) version of our PVF2 paint system used on our ARX™ and ZRX™ paint systems. This is the first time in the world, as far as we know, that a low gloss version will be used commercially. The application is for an airport where a combination of highly chemical-resistant paint and low glare (low reflectivity) is required. PCC worked with the building’s Architects and owners to develop the paint system for this project, and it will provide the best outcome possible offering maximum durability for the life of the material.

Hardcoat acrylics
PCC has also been working with our paint suppliers for a number of years to develop a harder version of our waterborne ZR8™ and AR8™ paint systems. The benefits are that the surface will be more resistant to scratching (approx 2-3 H pencil vs. F pencil for existing water borne systems), and this means less damage during transport and installation, and also improved metal marking resistance at the rollforming stage. This latter aspect is particularly relevant as it enables us to move more colours in our ZR8™ range to waterborne, thus improving our environmental impact and allowing us to use less solvent throughout our process.

Roofing Industries now in Christchurch
With a branch opening in Christchurch this month, Roofing Industries can now justifiably lay claim to being the only 100 per cent New Zealand owned and operated national long run roofing manufacturer.