An RCC water tank holds water under continuous hydrostatic pressure. Concrete contains pores and capillaries, while shrinkage, thermal movement, construction joints and pipe penetrations create possible leakage paths. The right solution must address the structure and its details before the lining is applied.
Weatherblazer’s approach combines surface preparation, construction-joint treatment, compatible coating application and a final water test. It is intended for both overhead and underground RCC tanks, with the system selected after inspecting the tank’s condition and use.
A coating alone cannot compensate for untreated joints, weak concrete, contamination or poor application. The method and verification are as important as the material.
The leak may appear at one point while water travels through the structure from somewhere else. Inspection must identify the pathway, not just the visible damp patch.
Wall-to-floor junctions and cold joints can become leakage paths if not properly detailed and repaired.
Shrinkage, thermal cycling, changing water loads and differential settlement can open existing weaknesses.
Voids from inadequate concrete compaction can create local routes for water migration.
Inlet, outlet, overflow and scour pipes need careful detailing at the concrete interface.
Contaminated or poorly prepared concrete can prevent a lining from bonding as intended.
Tiles are a finish, not a standalone waterproofing system; grout lines and hollow or debonded tiles complicate leak tracing and repair.
The primary waterproofing system is selected according to the water stored. WATERBLAZER EPFG-R is the specified food-grade lining for potable-water tanks, while WATERBLAZER 102 is used for suitable non-potable water-retaining structures. Final selection depends on tank condition, substrate, service conditions and the approved project specification.
Remove dust, oil, grease, release agents, curing compounds and other bond-breaking contamination. Repair unsound concrete and address cracks, honeycombing and weak areas before lining.
Give wall-to-floor joints, cold joints and pipe penetrations specific attention. The exact joint detail and repair material must be confirmed for the site before the coating stage.
A two-component, solvent-free, 100% solids epoxy coating described in the TDS for potable water storage tanks, pipelines and hygienic flooring. It cures to a dense, impervious, seamless surface that is easy to clean.
A flexible polymer-modified mineral slurry that may be specified for suitable underground water-retaining structures, sumps or STPs where movement and water pressure are key considerations. It is an alternative system for the appropriate application, not an automatic substitute for a potable-water lining.
The EPFG-R TDS specifies priming prepared concrete with WATERBLAZER EP-PRIME before applying the epoxy lining. Porous substrates may require two primer coats as directed by the TDS and project method statement.
Beyond the primary lining and primer, tank waterproofing may require compatible repair mortars, crack fillers and joint-detailing products. These are selected according to the defect, joint movement, tank use and approved method statement.
Polymer modifiers used in compatible repair mortar for patching honeycombed, damaged or locally defective concrete before the waterproofing system is applied.
Concrete repair supportReady-to-use crack-filling paste for suitable non-moving cracks and local defects. The crack must be assessed first; active or structural cracks need an appropriate engineered detail.
Crack and defect treatmentJoint-detailing tape used at suitable construction joints, wall-to-base junctions and pipe penetrations as part of the approved detailing system.
Joint and penetration detailingA two-component polymer-modified mineral waterproofing slurry for suitable non-potable water-retaining structures. It forms a flexible, crack-bridging coating and is selected for the tank and exposure conditions after site assessment.
Condition-specific flexible systemOverhead and underground tanks share many failure modes, but access, external moisture, structural condition and service requirements can differ. A site inspection determines the right scope.
Plan the waterproofing window, joint details, substrate acceptance and lining before handover. Avoid treating the coating as a substitute for sound concrete and proper joint design.
Specification before coatingEmpty and inspect the tank, trace the leakage paths, repair defects, prepare the surface and apply the approved system only after the substrate meets installation requirements.
Diagnosis before repairPlan access and safe work at height, protect the water supply during shutdown and account for exposure and repeated wetting/drying cycles.
Access & service planningAssess visible leakage, external moisture conditions, pipe penetrations and any evidence of movement or settlement before recommending rehabilitation.
Condition-led system selectionUse a lining documented as suitable for potable-water contact and plan the curing, cleaning and recommissioning requirements before returning the tank to service.
Documented suitabilityConfirm the stored liquid, temperature and chemical exposure before selecting a lining. Potable-water suitability alone does not establish compatibility with every chemical.
Use-specific compatibilityThe published Water Tank Waterproofing guide emphasises preparation, joint engineering, lining and verification. The precise repair details and material application must be confirmed for each tank and follow the current approved TDS/method statement.
Tiles can provide a finish, but grout lines and debonded areas can make water paths difficult to trace. A properly applied seamless lining avoids grout joints across the coated area; it does not remove the need to engineer construction joints and pipe penetrations.
Grout joints, hollow tiles and debonded adhesive can complicate leak tracing. Repairs may require tile removal to reach the underlying defect.
The specified epoxy system forms a dense, impervious coating with a smooth, cleanable surface. Its performance still depends on substrate preparation, detailing, application and curing.
Tell us whether your tank is overhead or underground, whether it stores drinking water, and what leakage or coating problem you are seeing. We will inspect the condition and recommend an appropriate system.
Request a Water Tank Site Inspection