Sika Damp-proofing Slurry Grey 25kg

Sika® Damp-Proofing Slurry – 25 kg

One-component, polymer-modified, cement-based waterproof coating supplied in 25 kg bags. Just add water to create a versatile slurry or mortar that can be brush-, trowel- or spray-applied to a wide range of substrates, offering effective waterproofing for floors and walls.

Key benefits

• Low odour alternative to bitumen coatings—safe and user-friendly.
• BBA certified and complies with BS EN 1504-2 (Principles 1.3, 2.2 and 8.2) for Type A waterproofing.
• Easy mixing and adaptable consistency for brush, trowel, or spray application methods.
• Excellent adhesion and workability—forms a reliable waterproof barrier.

Typical applications

• Tanking and internal waterproofing of domestic basements, cellars, and retaining walls.
• Interior and exterior waterproofing of concrete, brickwork, blockwork, and render surfaces.
• Lining of water tanks, planters, swimming pools, and similar structures.

Usage guidance

• Mix with clean water:
  • Slurry (brush): 4.5–4.7 L per 25 kg
  • Mortar (trowel): 4.0–4.25 L per 25 kg
  • Spray: 4.0–4.5 L per 25 kg
• Apply in two coats, with the second layer applied within 24 hours of the first.
• Minimum layer thickness: 2 mm for damp-proofing, 4 mm for waterproofing.
• Ambient and surface temperature during application must be between +5 °C and +35 °C.

Product details

• Pack size: 25 kg bag.
• Colour: Cement grey.
• Fresh mortar density: approximately 2.1 kg/L.
• Compressive strength: ~20 N/mm² at 3 days, ~40 N/mm² at 28 days.
• Flexural strength: ~5 N/mm² at 3 days, ~9 N/mm² at 28 days.
• Adhesion strength: > 1.5 N/mm² (failure in substrate).
• Fresh mortar density: ~2.1 kg/L. Water vapour permeability: ~3 MN·s·g⁻¹.
• Shelf life: 6 months in unopened packaging, stored in cool, dry conditions.

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