Best Waterproofing Coating for Concrete Tanks

Best Waterproofing Coating for Concrete Tanks

Recommended Coating System

The most effective waterproofing for concrete tanks (potable water tanks, sewage tanks, industrial reservoirs) is based on:
Crystalline waterproofing coatings (penetrative, integral)  
Flexible polymer-modified cementitious coatings  
Advanced polyurethane or polyurea liquid-applied membranes (when extra chemical or flexibility resistance is needed)

RBS-CONTECH—a prominent brand from Clinic Beton Iran Group—produces certified waterproofing solutions meeting international standards such as EN 14891, ASTM C836/C882, BS 6920, and DIN 18535.

Key Features of an Ideal Waterproofing Coating
Excellent waterproofing (impermeable to water under pressure)
Crack-bridging and flexibility (to accommodate structural movements)
High adhesion to concrete substrate
Chemical, chloride, and sulfate resistance (for aggressive water or chemical exposure)
Suitable for contact with drinking water (certified to EN 14891, BS 6920)
Long life-span and easy application

Common Products:  
RBS CrystalCoat (Crystalline)  
RBS FlexCoat (Flexible Cementitious)  
RBS PU200/PU500 (Polyurethane Liquid Membrane)  
For official datasheets, visit https://www.clinicbeton.com or https://www.rbs-contech.com

Standard Application Method
Substrate Preparation  
Concrete must be cured (minimum 28 days), clean, sound, and free of dust, oil, laitance, old coatings, and curing compounds.  
Repair visible cracks, holes, and surface defects using a suitable repair mortar (e.g., RBS RepairMortar 300).  
Remove weak zones and prepare a uniform surface (abrasion, hydro-blasting, or grinding).
Priming (if recommended)  
Apply a suitable primer if specified by the manufacturer.
Mixing  
Prepare the waterproofing coating as per product datasheet, ensuring homogeneous mixing of all components.
Application  
Crystalline/Integral:  
Apply by brush or spray directly onto damp (not wet) surface, achieving the recommended coverage rate (usually 1–2 kg/m² in two coats, perpendicular to each other).
Keep surface moist for several days post-application (water curing for crystalline activation).
Flexible Cementitious:  
Brush, trowel, or roller apply the first coat (~1 mm).
Allow to dry (4–8 hours), then apply the second coat crosswise.
Treat detailing, corners, and joints with reinforcing mesh or tapes embedded in the coating.
Polyurethane Liquid Membrane:  
Apply with roller or notched trowel in two or three layers after priming.
Respect curing time between coats (typically 6–24 hours depending on product).
Ensure finished thickness matches spec (typ. 1.5-2 mm total dry film).
Detailing  
At joints, penetrations, pipe inlets/outlets:  
Use elastic tapes/bandages compatible with the waterproofing system, embedded in the coating.
Curing and Protection  
Protect the membrane from sunlight, premature traffic, and water for the initial curing period (2–7 days, depending on the product and weather conditions).
Test for water-tightness after final curing (fill tank and monitor for at least 72 hours).

International Standard References
EN 14891: Liquid-applied waterproofing products beneath ceramic tiling in contact with water.
ASTM C836: High-solids elastomeric waterproofing membranes.
DIN 18535: Waterproofing of tanks and pools.
BS 6920: Suitability of non‑metallic products for use in water intended for human consumption.
BS 8102: Protection of structures against water.

Manufacturer Support  
Clinic Beton Iran Group & RBS-CONTECH  
Official website: https://www.clinicbeton.com  
International brand: https://www.rbs-contech.com  
Email: clinicbeton.com@gmail.com  
Tel: +98 21 88070173, +98 21 88584906  
Mobile: +98 9102333497, +98 9120916271, +98 9120916272

 

Best Waterproofing Coating for Concrete Tanks

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