Waterproofing Spec - Dekro Paints

Waterproofing

General:

Dekro Rainproof system can be used on: new concrete roofs (after full curing of concrete), asbestos roofs, galvanised iron roofs, new timber roofs, expansion joints and flashings. Also on roofs previously treated with Asphalt, Malthoid or similar combination roof coverings.

Preparation:

STANDARD APPLICATION PROCEDURE:

  1. Apply to the substrate one primer / sealer coat of Rainproof, diluted with 20% water and allow to dry (drying time is ± 4 hours at standard condition 25ºC and 50% humidity).
  1. Apply one coat of Rainproof as supplied, to an area not exceeding one metre by the width of the Polyester Fabric used (Bidum) and firmly press the fabric into the coating, before the Rainproof coating begins to dry. Repeat the process in one metre lengths at a time. Allow the application to dry before proceeding. (Drying time is ±4 hours at standard condition 25ºC and 50% humidity). If the polyester fabric becomes rain saturated, allow to dry out completely over an extended period before proceeding with the application process.
  1. Apply one coat of Rainproof, diluted with 20% water, to penetrate and saturate the Polyester fabric (Bidum) surface. Allow the application to dry thoroughly before proceeding. (Drying time is ±4 hours at standard condition at 25ºC and 50% humidity).
  1. Finally apply two coats of Rainproof as supplied, allowing to dry between coats. (Drying time per coat is ±4 hours at standard condition 25ºC and 50% humidity).

New Concrete Roofs:
Screeding to be inspected and made good if necessary. Scrape all loose materials and sweep clean. Apply standard application procedures 1 – 4.

Roofs previously treated with old Asphalt, Malthoid or similar combinations:
Remove all loose material, clean out and fill cracks. Wash and brush down roof to clean surface. Apply standard application procedures 1 – 4.

Asbestos Roofs:
Clean down by brushing, treat where necessary with Hydrowash Fungicidal. Allow to dry and remove dust. Treat screw heads by priming with Hydrobond 44. Treat cracks by priming with one coat Rainproof, diluted with 20% water.

Allow to dry. Apply one coat Rainproof as supplied. Press into the coating a suitable patch of Polyester Fabric (Bidum) before the coating dries. Allow to dry. Apply to entire roof. Including patched-up area one coat of Rainproof, diluted with 20% water. Allow to dry. Apply two final coat of Rainproof as supplied.

Galvanised Iron Roofs:
Wire brush and wash down to remove all surface contamination. Treat rust areas with rust neutraliser after sandpapering. Treat screw heads by priming with Hydrobond 44. Treat minor holes by applying one coat Rainproof as supplied. Press into the coating a suitable patch of Polyester Fabric (Bidum) before the coating dries.

Apply one coat of Rainproof, diluted with 20% water, over the patched-up area. Allow to dry. Apply to the entire area, including patches, two coats of Rainproof as supplied, allowing to dry between coats.

New Timber Roofs:
Ensure that the timber is completely dry. Apply standard application procedures 1 – 4.

Flashings:
Apply standard application procedures 1 – 4, ensuring that the ends of the Polyester Fabric (Bidum) are not exposed.

First Coat: Suitable Dekro Primer
Second Coat: Suitable Top Coat
Third Coat: Suitable Top Coat