Painting old unpainted cementitious surfaces - in good condition

Note: Refer to the PDF flowchart for a visual of the steps below:

1. Apply Resene Moss & Mould Killer.

2. Wash down using high pressure waterblaster OR wash down using Resene Paint Prep and Housewash.

3. Spot prime galvanised metal with Resene Galvo-One and rusted metal with Resene Rust-Arrest.

4. Prime using Resene Sureseal.

5. Fill cracks and voids:

   1. Cracks under 1mm, use Resene Brushable Crack Filler.
   2. Cracks over 1mm, use Selleys No More Gaps exterior formulation or similar.
   3. Holes and voids, use either Resene Jointflex or an approved masonry filler.

6. Refer to topcoat systems flowcharts.

Things to consider

• What is the condition of the surface?
• Does it have any moss, mould or lichen present?
• Are there any cracks or voids that will need filling?
• Do you have any waterproofing issues?
• Are you going to do the work yourself?
• What is the approximate size of the area to be painted – how smooth (or rough) is the surface?

Notes:

1. Old unpainted cementitious surfaces will be contaminated with moss and mould, windblown salt and other contaminants. They will also be powdery and most likely dirty. This is why we recommend Resene Moss & Mould Killer and a thorough clean by either waterblasting or a thorough scrub using Resene Paint Prep and Housewash .

2. We recommend Resene Sureseal because it will:

   • Hold back any salt staining that could occur.
   • Bind the surface up if it is powdery or eroded.

   While Resene Concrete Primer could be used instead, Resene Sureseal provides a ‘belt and braces‘ approach.

3. Spot prime galvanised flaking areas with Resene Galvo-One and rusted metal with Resene Rust-Arrest or Resene ArmourZinc 120 if the rust can be removed easily.

Key accessories essential to complete the job

• 50-75mm Resene Blue or Resene Professional brush for cutting in
• Extension pole
• PAL No.4 roller sleeve
• Resene Brushable Crack Filler
• Resene Moss & Mould Killer
• Roller tray and handle
• Selleys exterior gap filler or Resene Epox-O-Bond
• Turps for cleaning up

Add-ons – to make the job easier or quicker

• 35-50mm broad knife (for filling)
• Dropsheet
• Rubber gloves and eye protection

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