Flexible Liquid-Applied Waterproof Membrane for Internal Tanking Applications

Biokil Crown Premium Liquid Tanking is a high-performance, single-component, liquid-applied waterproofing membrane designed for use in internal tanking and damp-proofing systems. It forms a seamless, highly elastic barrier that prevents water ingress in below-ground structures such as basements, lift pits, and retaining walls. Applied by brush, roller, or spray, the membrane cures to form a tough, flexible coating suitable for concrete, masonry, blockwork, and render surfaces.

Key Features & Benefits

• Seamless Protection: Forms a continuous, joint-free waterproof membrane with excellent flexibility.
• Highly Elastic: Accommodates minor substrate movement and bridges hairline cracks.
• Easy Application: Ready-to-use formula for brush, roller, or spray application — no mixing required.
• Versatile Use: Suitable for internal tanking in basements, cellars, lift shafts, and retaining structures.
• Low VOC & Solvent-Free: Safe for use in enclosed spaces with minimal odour and environmental impact.

Product Details

• Type: Liquid-applied waterproofing membrane
• Form: Single-component, ready to use
• Colour: Grey
• Coverage: Approx. 1.5–2.0 kg/m² per coat (depending on substrate and application thickness)
• Application Method: Brush, roller, or airless spray
• Drying Time: Touch dry in 2–4 hours; full cure in 24–48 hours
• Pack Size: 20kg

Performance & Technical Details

• Abrasion Resistance: Not suitable as a final surface finish on floors subject to foot or vehicle traffic. Protect with a suitable floor covering such as Mapei Latexplan, tiles, carpet, or linoleum.
• Positive Water Pressure Resistance: Resists pressure equivalent to a 20-metre head of water.
• Negative Water Pressure Resistance: When applied in basements, the membrane should be overcoated with a render — Biokil Crown Renovating Render is recommended.
• Water Vapour Permeability: Less than 4g/m²/24h at 25ºC / 75% RH (to BS 3177, Payne Cups, 0.6mm dry film thickness).
• Carbon Dioxide Resistance: A 0.6mm dry film offers resistance equivalent to 100 metres of still air, exceeding the 50-metre requirement for anti-carbonation coatings.
• Methane Resistance: RAPRA report CT 26076 shows a permeability of 79 mL/m²/day under 1 bar partial pressure — approximately 10 times more resistant than low-density polyethylene film.

Application Instructions

1. Prepare Surface: Ensure the substrate is clean, stable, and free from oil, dust, or contaminants.
2. Prime if Required: Apply a compatible primer to porous surfaces for better adhesion.
3. First Coat: Apply a consistent layer using a brush, roller, or airless spray.
4. Second Coat: Apply a second coat once the first is dry (typically after 2–4 hours), in a perpendicular direction for best coverage.
5. Curing: Allow 24–48 hours for full cure before backfilling, overcoating, or applying final finishes.

Limitations

• Not suitable for surfaces with active water ingress without proper drainage provision.
• Do not apply at temperatures below 5°C or onto wet, frozen, or contaminated surfaces.
• Not designed for external applications unless fully protected from UV exposure.

Health & Safety

Always wear suitable PPE during use, including gloves and eye protection. Avoid inhalation of vapours and contact with skin or eyes. Refer to the Safety Data Sheet (SDS) for comprehensive guidance.