Design Criteria

Vetotop AC441 should generally be applied in two coats to achieve a total dry film thickness of not less than 200 microns to accommodate substrate cracking up to 2 mm and cyclic movement up to 0.3 mm. It is possible to achieve the total dry film thickness in one coat; however, this depends on the substrate type, and the finish required. Trials are recommended before the full application to ensure the finish meets the client's requirements. Vetotop AC441 must be applied to the substrate at the coverage rates suggested achieving the correct protective properties. 

Priming
Firstly, apply Vetoprime AP443 in one or more coats until achieving the recommended application rate of 0.4 liters per square meter. This is best accomplished by using portable spray equipment. A uniform surface appearance (sheen) should be conducted.
Allow the primer to dry for a minimum of two hours (at 20°C) before overcoated with Vetotop AC441.

Application
To obtain the Vetotop AC411 system's protective properties, the correct rates of application and overcoating times must be observed.
Apply Vetotop AC441 in two coats. The first coat can be thinned with clean water depending on the substrate. The recoat time for the second coat is two hours. If necessary, a third coat can be applied to achieve a hiding power.
No gaps or 'raw edges' must appear in the finished coating. Take special care to provide an unbroken layer at the external corners and similarly exposed protrusions.
Vetotop AC441 may be applied by the use of suitable brushes, rollers, or airless spray equipment.

Cleaning
Remove Vetotop AC441 from tools and equipment with clean water immediately after use.

All surfaces should be dry and free from any contamination, traces of mold release oils, and curing compounds. This is best achieved by lightly grit-blasting the surface. Where moss, algae, or similar growths have occurred, treatment with a proprietary biocide should be carried out after the grit-blasting process.
Where required to apply over existing sound coatings, conduct trials to ensure compatibility and retention of the bond between the underlying and substrate layer. It is essential to produce an unbroken coating of Vetotop AC441. Fill surfaces that contain blow-holes or pitting areas using Vetorep CR523, a cementitious fairing coat. Level rougher substrates by using a cementitious product from Saveto Concrete Repair Range.

• Vetotop AC441 is formulated for application to clean, sound concrete or masonry. Where required to apply over existing sound coatings or paints, conduct trials to ensure compatibility and retention of the bond between the underlying layer and the substrate.
• Do not commence Vetotop AC441 application if the temperature of the substrate is below 5°C.
• Do not apply the product in windy conditions where early-age dust adhesion may occur, or where rain is likely within 2 hours at 20°C, or within 20 hours at 5°C.
• Do not consider the use of Vetotop AC441 for areas subjected to exposure to ponded water. Consider using Vetotop AC442 on this occasion.