You hear water flowing even when the toilet hasn’t been flushed.
causes of leakage
Worn Flush Valve Seal
The flush valve is responsible for releasing water into the toilet bowl during flushing. Over time, the rubber seal deteriorates, allowing water to leak continuously from the tank into the bowl.
Loose Pipe Joints
Pipe joints behind the wall can loosen due to pressure or corrosion. Even a small gap can result in long-term water leakage behind tiled surfaces.
Faulty Inlet Valve
If the inlet valve becomes defective, it may not shut off properly, leading to continuous water intake and overflow. This overflow may leak from the cistern into walls or floors.
Overflow Malfunction
Overflow pipes are designed to redirect excess water safely. When damaged or blocked, water may leak into concealed cavities rather than being discharged correctly.
Cracked Tank or Internal Chamber
Hairline cracks in plastic or ceramic tanks are difficult to detect but can leak water gradually into hidden areas, causing dampness and structural damage.
Improper Installation of Cistern
Improperly sealed joints or misaligned connectors during initial installation can cause the system to leak over time, especially in concealed setups where inspection is difficult.
detecting Concealed Cistern Leaks
We take a non-invasive, methodical approach to diagnosing cistern and water tank leaks. Our tools and techniques are designed to protect your property while pinpointing the issue accurately.
🔹 Thermal Imaging
Using heat-sensitive cameras, we scan the wall area behind the toilet to locate temperature anomalies caused by water seepage.
🔹 Moisture Meters
These devices detect moisture levels behind walls and tiles without breaking them. High moisture readings indicate leak presence and location.
🔹 Coloured Dye Test
We add harmless coloured dye to the water tank or cistern and monitor whether the dye appears in unintended locations like the bowl or nearby wall cracks.
🔹 Pressure Testing
This involves testing the plumbing system’s pressure stability. Drops in pressure suggest leakage in the hidden pipework or cistern housing.
By combining multiple methods, we ensure a precise and efficient diagnosis with minimal disruption to your bathroom or toilet structure.
Cistern Tank Restoration
A leaking concealed cistern can lead to water wastage, damage to bathroom fixtures, and higher water bills. Timely cistern tank restoration ensures your toilet operates efficiently and prevents further structural issues. Our experts carefully assess and repair the cistern for long-lasting performance. Key steps include:
🔹 Inspecting the Cistern – Checking for cracks, worn seals, or damaged components causing leaks.
🔹 Repairing or Sealing Cracks – Applying appropriate sealants or repairing minor cracks in the cistern tank to stop water seepage.
🔹 Replacing Faulty Components – Installing new flush valves, inlet valves, or washers to restore proper function.
🔹 Testing for Leaks – Running multiple flush cycles to ensure the repair is secure and leak-free.
🔹 Final Inspection and Adjustment – Ensuring the cistern operates smoothly, flushes efficiently, and maintains proper water levels.
Repair solutions for Concealed Cistern Leaks
At All Plumbing.SG, we handle a wide range of water tank and concealed cistern leak issues, using precision tools and proven techniques.
🔹 Exposed Toilet Tank Repairs
For traditional floor-mounted toilets with visible water tanks, we replace worn flush valves, fix overflow pipes, and change inlet valves to stop leaks and restore proper operation.
🔹 Concealed Cistern Leak Detection
Concealed cisterns are popular in modern homes but difficult to access. We use non-destructive methods to detect internal leaks and identify the exact source of water loss within wall panels or false walls.
🔹 Internal Valve & Seal Replacement
Flush valve seals, inlet valves, and overflow components inside cisterns wear out over time. We replace these parts efficiently without needing to dismantle the entire wall structure.
🔹 Cistern Resealing & Joint Reinforcement
Leaks from concealed joints or behind-the-wall pipe connections are resolved by resealing pipe inlets and reinforcing key connection points using industry-grade sealants and techniques.
🔹 Structural Leak Rectification
In cases where prolonged leakage has affected walls, tiles, or flooring, our team will repair the plumbing issue and provide advice on restoration works such as waterproofing or tile repair.
🔹 System Upgrade or Replacement
When the existing cistern or water tank is beyond repair or outdated, we can replace the unit with a modern flushing system. Our team ensures compatibility and clean installation with minimal disruption.
Pre-Service Tips
To help our plumbers work efficiently, you can take a few simple steps before our visit:
🔹 Turn Off the Water Supply
Locate and close the stop valve behind or beside the toilet. This prevents further leakage.
🔹 Avoid Flushing the Toilet
Each flush adds more water into the system and may worsen the leak or cause overflow.
🔹 Dry the Area if Possible
If there’s visible water on the floor or walls, wipe it up. It helps us identify the active leak more quickly.
🔹 Document Symptoms
Note any noises, smells, stains, or other unusual signs. Providing these details can assist in rapid diagnosis.
🔹 Clear Access to the Toilet
Remove any floor mats, bins, or obstacles around the toilet area so we can begin our inspection immediately.
testimonials
Leaks can be caused by worn-out flush valves, inlet valves, flappers, seals, cracks in the cistern tank, high water pressure, or faulty installation.
Minor issues like tightening loose fittings may provide temporary relief, but most concealed cistern leaks involve hidden components. DIY repairs can worsen the problem, damage the cistern, or create safety risks. Professional repair is recommended.
Minor repairs can take a few hours, while extensive damage requiring component replacement or cistern restoration may take several hours to a day, depending on the issue.
Call a licensed plumber as soon as you notice continuous water running, unusual sounds, damp patches, or higher water bills. Early intervention prevents water wastage and potential bathroom damage.
We are a certified company driven by our excellent customer service and client experiences. We are skilled, honest, reliable, and experienced in all aspects of residential plumbing. We are local and striving to make a name for ourselves within the community.
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