MasterSeal® 583 Single-component cement-based waterproofing coating | MCT CHEMICALS | MASTER BUILDER SOLUTIONS

When mixed with clean water, MasterSeal 583 creates a highly durable waterproof coating for concrete and masonry. It should be applied in two coats, each at a minimum thickness of 2 mm, using a stiff brush, broom, or spray.

FIELD OF APPLICATION
Waterproofing of:

• Basements
• Foundations
• Water reservoirs
• Tunnels
• Floors and walls in shower and bathroom areas before applying a decorative finish

FEATURES AND BENEFITS

• Withstands both positive and negative water pressure
• Suitable for both interior and exterior use, above and below ground
• Allows water vapor to pass through
• Strong bond strength, becoming an integral part of the substrate
• Requires only water for mixing
• Can be applied by brush or spray
• Can be applied to a damp substrate
• Equipment cleans up easily with water
• Non-solvent based

TESTS AND APPROVALS

• British Board of Agrément Certificate No. 89/2138/fifth edition
• Meets class 0 rating according to Building Regulations 1991 for England and Wales, approved Document B, Appendix A12

APPLICATION METHOD
For tanking applications, refer to the Basement Waterproofing Guide.

Substrate Quality
The substrate must be clean, structurally sound, and mechanically keyed. Remove all coatings, defective renders, foreign matter, formwork treatments, and contaminants that may hinder adhesion.

(a) Surface Preparation
Prepare substrates by abrasive blasting or high-pressure water treatment. Avoid scabbling or aggressive methods.

• Ensure all mortar joints are flush-pointed.
• Repair with MasterSeal 590 and/or MasterEmaco mortar as needed.
• Prepare wall/floor intersections by cutting a 20mm by 20mm chase along the junctions and filling with MasterSeal 590, finishing with an angle fillet.
• Divert water infiltration from the treated substrate through drainage or concentrate it at weepholes, which should be sealed with MasterSeal 590 after the final coat of MasterSeal 583.
• Basements in areas with high soil or groundwater sulphates may need a pre-treatment render. For details, consult BASF Plc Construction Chemicals.

(b) Mixing

• Water content: 5.0 – 5.8 liters per 25 kg bag (typically 5.4 liters). Adjust based on ambient conditions, but do not exceed 5.8 liters of water per bag.
• Mechanical mixing: Blend the powder into the mixing liquid using a slow-speed drill (400-600 rpm) with a suitable mixing paddle. Mix until a thick, lump-free consistency is achieved. Allow the mixture to stand for 5-10 minutes for full saturation, then re-mix and add a small amount of water if necessary to restore consistency.

Consistency
Do not exceed the recommended liquid amount. The final mixture should have a thick, creamy, lump-free consistency that can support the weight of a stiff brush.