Internal tank walls
A key concrete tank inspection and treatment point.
PROFESSIONAL CONCRETE TANK PROTECTION
Water Tank Waterproofing in Karachi
Professional inspection-led waterproofing for overhead and underground concrete water tanks.
Concrete tanks can leak through cracks, construction joints, weak wall-floor connections and deteriorated internal surfaces. Pak Chemical Services identifies the likely leakage pathway before recommending repair and waterproofing.
Overhead tanks usually experience water pressure from inside, while underground tanks may also face moisture or groundwater pressure from outside. The selected treatment therefore depends on the actual site condition.
• INSPECTION BEFORE TREATMENT
Professional Water Tank Leakage Inspection and Waterproofing
Professional Water Tank Waterproofing in Karachi involves more than coating the visible wet area. Water may travel through concrete and joints before appearing outside. The scope depends on whether leakage is localized or widespread, and significant structural cracking may require separate assessment.
Tank floor
A key concrete tank inspection and treatment point.
Wall-floor junctions
A key concrete tank inspection and treatment point.
Construction joints
A key concrete tank inspection and treatment point.
Concrete cracks
A key concrete tank inspection and treatment point.
Pipe penetrations
A key concrete tank inspection and treatment point.
Inlet and outlet surroundings
A key concrete tank inspection and treatment point.
Overflow openings
A key concrete tank inspection and treatment point.
Previous waterproof coating
A key concrete tank inspection and treatment point.
External damp areas
A key concrete tank inspection and treatment point.
• WARNING SIGNS
Common Signs of Water Tank Leakage
Small defects may show gradual signs around the structure. Plumbing lines, valves and outlets should also be checked before the tank itself is blamed.
- ✓ Water level dropping without normal usage
- ✓ Wet patches on external tank walls
- ✓ Damp ceilings below overhead tanks
- ✓ Moisture around underground tank walls
- ✓ Visible concrete cracks
- ✓ Water along construction joints
- ✓ Leakage near pipe penetrations
- ✓ Damp wall-floor junctions
- ✓ Peeling previous coating
- ✓ Surface deterioration
- ✓ Repeated repair failure
- ✓ Moisture around the tank base
• COMMON CAUSES
What Causes Concrete Water Tanks to Leak
The repair method depends on crack condition, joint type, surface strength and the direction of water pressure.
Concrete Cracks
Shrinkage, movement, settlement, poor curing or deterioration can create stable or moving cracks. Cracks must be assessed and repaired before coating.
Weak Construction Joints
Wall-to-floor joints, vertical wall joints, cold joints and old-to-new concrete connections can become water pathways when bonding is weak.
Wall-to-Floor Junction Leakage
This transition remains in constant contact with stored water. Treatment may need to extend across both surfaces instead of filling only the visible line.
Pipe Penetrations
Inlet, outlet and overflow openings can leak through weak grouting, movement or deteriorated seals. Pipes and fittings should also be checked.
Porous or Deteriorated Concrete
Weak plaster, honeycombing, surface deterioration and damaged repairs may allow moisture movement and require preparation before treatment.
Failed Previous Waterproofing
Poor preparation, untreated cracks, incompatible materials, insufficient curing and weak repairs can cause previous coatings to fail.
• TANK TYPE
Underground vs Overhead Water Tank Waterproofing
Different tank locations create different water-pressure and access conditions.
Underground Water Tanks
Surrounding soil can create external moisture pressure in addition to the stored water pushing outward. Internal walls, floors, joints, pipe openings and accessible external surfaces are assessed. Internal treatment can be practical when excavation is not possible.
Overhead Water Tanks
Stored water pushes against walls and floors from inside, while exterior surfaces face sunlight and weather. Cracks, wall-floor junctions, pipe openings, base slabs and supporting areas are inspected before the treatment scope is selected.
• INTERNAL PROTECTION
Internal Water Tank Waterproofing
Internal treatment is commonly used because the water-contact surface can be accessed directly. The tank normally needs to be drained and cleaned; slime, dust, salts, weak concrete and failed coating must be removed before localized repairs and the main system are applied. Product suitability, curing and refill guidance must follow manufacturer documentation and site conditions.
• WORKFLOW
Our Water Tank Waterproofing Process
The exact sequence is adjusted to tank condition and the selected material system.
01
Tank Inspection
Inspect internal walls, floor, joints, cracks, pipe openings, previous coating and visible external dampness.
02
Leakage Assessment
Review water-level loss, leakage patterns, plumbing points and likely internal or external pressure direction.
03
Draining and Cleaning
Empty the tank where required and clean slime, dust, salts, loose coating and contamination from treatment surfaces.
04
Surface Preparation
Remove weak material, open suitable cracks and prepare joints and pipe penetrations for stable bonding.
05
Crack and Joint Repair
Treat stable cracks, weak junctions, construction joints and pipe surroundings with compatible repair materials.
06
Waterproofing Application
Apply the selected system with uniform coverage, additional corner treatment and multiple coats where specified.
07
Curing and Inspection
Allow the material-specific curing period, then inspect coverage, edges and repaired areas before refill or testing.
08
Water-Retention Test
Where suitable, carry out controlled filling and observation after curing to check treated areas and plumbing connections.
• TARGETED REPAIRS
Water Tank Crack and Joint Repair
Stable cracks, wall-floor junctions, construction joints and pipe penetrations are treated before the broader coating. Moving or structural cracks may need a different repair method or specialist assessment. Waterproof coating should not be presented as a structural repair.
• PROPERTY TYPES
Water Tanks We Inspect and Treat
The final scope depends on tank type, access, leakage source and concrete condition.
✓ Residential properties✓ Apartment buildings✓ Commercial buildings✓ Factories and warehouses✓ Schools and institutions✓ Hospitals and clinics✓ Hotels and guest houses✓ Industrial facilities✓ Mosques and community buildings✓ Underground storage tanks✓ Overhead RCC tanks
• PRACTICAL VALUE
Benefits of Professional Water Tank Waterproofing
Professional treatment focuses on the actual defect and material-specific application rather than repeated surface patching.
✓ Better identification of leakage source✓ Reduced water loss✓ Repair of cracks and weak joints✓ Improved protection of surrounding surfaces✓ Better treatment around pipe penetrations✓ Removal of failed coating✓ Suitable overhead or underground approach✓ Clear curing guidance✓ Optional retention testing where practical✓ Reduced repeated patchwork
• QUOTATION FACTORS
Water Tank Waterproofing Cost in Karachi
Cost depends on tank size and depth, overhead or underground location, affected area, number of cracks and joints, pipe penetrations, failed coating removal, cleaning, access, material system, coats, curing and testing. Two tanks of the same capacity can require different work, so inspection gives a more reliable quotation than a fixed rate. No fixed prices are invented.
• WHY PCS
Why Choose Pak Chemical Services?
Pak Chemical Services follows an inspection-led approach for Water Tank Waterproofing in Karachi: checking leakage patterns, cracks, joints and pipe penetrations; distinguishing plumbing defects from concrete leakage; removing weak material; selecting treatment according to pressure direction; following curing guidance; and completing final inspection. Any material suitability, warranty or expected life should be stated in the written quotation.
• SERVICE AREAS
Water Tank Waterproofing Services Across Karachi
Customers can share tank photographs, videos and location through WhatsApp for an initial discussion. Physical inspection may still be required.
✓ DHA✓ Clifton✓ Gulshan-e-Iqbal✓ Gulistan-e-Johar✓ PECHS✓ Nazimabad✓ North Nazimabad✓ Korangi✓ Saddar✓ SITE Area✓ Nearby Karachi locations
• RELATED PCS PAGES
Related Waterproofing Services
Use these natural links to explore PCS services and request an inspection.
• QUESTIONS ANSWERED
Frequently Asked Questions About Water Tank Waterproofing
Why does a concrete water tank leak?
Common causes include concrete cracks, weak construction joints, wall-floor junctions, pipe penetrations, porous concrete and failed previous waterproofing.
Can an old leaking concrete tank be waterproofed?
Many existing concrete tanks can be repaired and waterproofed after inspection, preparation and treatment of damaged areas.
Do you waterproof underground water tanks?
Yes. Underground concrete tanks can be assessed according to internal leakage and possible external moisture pressure.
Do you waterproof overhead water tanks?
Yes. Overhead concrete tanks can be treated for cracks, joint leakage, seepage and deteriorated surfaces.
Can water tank cracks be repaired?
Many stable cracks can be repaired. Significant, moving or structural cracks may require additional assessment.
Can leakage around tank pipes be treated?
Often yes, after checking the pipe, fitting, surrounding concrete and existing seal.
Does the entire tank always need waterproofing?
No. Localized defects may need targeted repair, while widespread leakage can require broader treatment.
How long before the tank can be filled?
The curing period depends on the selected system, environmental conditions and repair work; no universal refill time should be assumed.
Is a water-retention test required?
A controlled retention test may be useful where practical after the complete curing period.
Is every material safe for drinking-water tanks?
No. Potable-water suitability should only be claimed when the selected material has supporting manufacturer documentation.
How much does Water Tank Waterproofing in Karachi cost?
Cost depends on tank size, surface condition, cracks, joints, access, previous treatment and the required system.
Do you inspect before waterproofing?
Yes. Inspection helps identify cracks, joints, damaged surfaces and other possible leakage paths before finalizing scope.
• GET IN TOUCH
Request a Water Tank Inspection in Karachi
Recurring water loss, damp surrounding surfaces and visible cracks can indicate a tank problem, but the source should be identified before repair begins.
Contact Pak Chemical Services for professional Water Tank Waterproofing in Karachi. Share the property location, tank type and photographs or videos to request an inspection and quotation.