Resene Popular Paint Systems –
Roofing products and roof paint preparations: training notes
This web page is an edited version of the Resene Best System Selling training notes provided to Resene staff and is provided to enable you to gain a greater understanding of the substrates and paint systems you may encounter in your decorating project. It is impossible to cover all decorating scenarios in a single document, so if you are in doubt about any aspect of your project please contact Resene for assistance.
Select the roof product type you will be painting from the list below to view how to prepare and finish the surface.
Preparation flowcharts
Note: Refer to the PDF flowchart for a visual of the steps below:
Wash thoroughly using Resene Roof Wash and Paint Cleaner then rinse thoroughly
Apply Resene Galvo-Prime or Resene Galvo One (2 coats for severe marine environment)
Wash between coats if salt is suspected - See notes
Topcoat options:
1To optimise the benefits of the Resene Cool Colour topcoat use Resene Cool Primer.
New galvanised iron is much less common today than 10 years ago. In the roofing market it has been replaced by Zincalume, which as the name indicates is a blend or mixture of zinc (galvanising) and aluminium.
During the manufacturing process (often called ‘forming’), an oil or thin acrylic coating is applied to the surface of each sheet. This layer will remain on the surface until it either erodes away after exposure to the weather (this can take upwards of a year) or it is removed manually. This is why Resene Roof Wash and Paint Cleaner is recommended for new Zincalume or galvanised iron. To work, the primer must be applied to the metal surface, as any unremoved form oil or acrylic layer will inevitably lead to the paint delaminating or falling off.
The overlap areas of the roof should be primed top and bottom before a new roof is put up. These areas will always corrode first if this isn’t done leading to premature rusting.
Waterborne Resene Galvo-Prime may be used in place of solvent borne Resene Galvo One. It is better for the environment and performs as well or better on new iron. However, the older the iron the more likely it is there will be corrosion of the zinc and aluminium. This is often called white rust. Resene Galvo One is much more effective over white rust than Resene Galvo-Prime.
If two coats of primer are required it is fine to mix and match. So Resene Galvo-Prime or the Resene Cool Primer may be applied over Resene Galvo One.
Any salt that is deposited on the roof between coats or after preparation must be rinsed away. In practice this means if the roof is near the sea and there has been an on shore breeze, hose the roof down and allow to dry before applying the next coat.