WP342 Waterproofing Concrete Balconies – Pavers on Pedestals


  1. All surfaces to be waterproofed must be firm, clean, dry, sound and smooth. All grease, oil, wax, curing compounds, loose material, paint and any other contaminants must be removed, masonry surfaces must be pointed flush and surface defects repaired. New concrete must be cured for a minimum of 28 days.
  2. External corners to be waterproofed must be bevelled to ensure a smooth transition of membrane from vertical to horizontal surfaces.


  1. Waterproofing installation shall be in accordance with AS 4654.2 Waterproofing Membranes for External Above-Ground Use.
  2. Install a puddle flange to all waste pipes, ensuring that puddle flanges are recessed into the substrate.
  3. Install an appropriate fillet (bond breaker) to all transitions using WPA FC.

    WPA FC is a high-performance, fast-cure, one-component polyurethane sealant.

  4. Apply WPA SB primer to some non-porous surfaces such as puddle flange and waterstop angle using the 2 cloth method. (The 2-cloth method is carried out as follows: Dampen a clean cloth with an appropriate amount of WPA SB primer, and wipe evenly over the non-porous substrate utilizing a rubbing action. With a clean dry cloth, immediately remove all primer residues by implementing a buffing action).

    WPA SB is a fast-drying, solvent-based primer, with exceptional penetrating properties. WPA SB primer is designed to assist in improving adhesion on porous and some non-porous substrates.

  5. Apply WPA 460 or WPA 560 primer to the substrate being waterproofed.

    WPA 460 is a two-part, water-based epoxy primer, used to seal concrete and masonry surfaces.

    WPA 560 is a two-part, water-based epoxy primer, designed as a water and vapour-proof coating under waterproofing membranes.

  6. Apply WPA 992UV membrane to the floor area in a minimum of two coats to achieve the required dry film thickness. Ensure that the previous coat has completely dried before applying the subsequent coat(s).
    NOTE: Where surface finishes such as render, tiles and paint are required, this area should be waterproofed with WPA 230UV – Refer to Detail 2 on the following page.

    WPA 992UV is a thixotropic, one-part, liquid-applied, moisture-cured polyurethane waterproofing membrane, suitable for waterproofing most applications.

    WPA 230UV is an elastomeric, fibre-reinforced, water-based polyurethane membrane system designed for exposed or under-tile applications.

  7. Install overflashing where required.
  8. Install suitable pavers or tiles using an appropriate pedestal system.