8 Warning Signs You May Have a Hidden Water Leak

ACS Plumbing • September 3, 2025

A water leak isn’t always an obvious burst pipe or dripping tap. Many leaks develop out of sight, quietly causing structural damage, inviting mould, or driving up water bills. These hidden leaks can lurk behind walls, under floors, or within slab foundations—going undetected for months.

Whether you’ve recently noticed musty odours or your water meter’s spinning when no one’s using water, there’s usually a silent culprit behind it. Understanding the early signs of a hidden leak is critical to avoiding serious—and expensive—plumbing damage. Here’s how you can spot the warning signs of a water leak and what to do about them.

1. Unexplained Spikes in Your Water Bill

An unexpectedly high water bill is often the first red flag. If your water usage habits haven’t changed but your costs have, it’s time to investigate further.

Unseen leaks—especially in underground pipes or within wall cavities—can allow hundreds of litres to seep away daily. Unfortunately, many property owners don’t notice until the bill arrives.

Some signs your water bill could be leak-related:

There’s no increase in household water usage, but your bill has risen sharply
Water meter readings show continuous usage overnight
You’ve ruled out appliances like dishwashers or irrigation systems as the cause

Ignoring these signs risks wasting water and money. A licensed plumber can perform detailed leak detection to pinpoint the issue.

2. Damp Patches on Walls or Floors Aren’t Just Cosmetic Issues

Have you noticed a soft patch in the carpet? Perhaps a stain on the wall that wasn’t there last month? These are often early visual cues that water escapes somewhere it shouldn’t be.

While rising damp can come from outside, leaks from interior plumbing can create similar symptoms.

Watch out for:

Bubbling or peeling paint on interior walls
Floorboards lifting or warping unexpectedly
Persistent wet spots that return after cleaning or drying

If the area is warm to the touch, the leak might come from a hot water line—another job for a plumber with thermal imaging capabilities.

3. The Sound of Running Water When Taps Are Off Shouldn’t Be Ignored

It’s one of the most overlooked signs—hearing water trickling, dripping or hissing when every tap is tightly shut. These sounds usually indicate water is escaping inside the walls or under the slab.

This is especially concerning if:

You hear faint hissing or dripping at night when the house is quiet
The toilet isn’t running, but water sounds persist
You suspect the leak may be under concrete or tile flooring

Acoustic leak detection can isolate the sound source, even if it’s buried deep in the structure.

4. Mould & Mildew Growth Can Signal Moisture from Hidden Leaks

Finding mould in places that should remain dry—like behind cabinets, wardrobes, or in corners of bedrooms—often points to excess moisture caused by a leak.

Mould spores thrive in damp, dark spaces and multiply quickly when water is present. Left untreated, this can create a structural issue and a serious health concern.

Warning signs of water-leak-induced mould:

Musty smells in otherwise dry areas of the house
Recurring black or green spots on walls or ceilings
Mould growth in rooms with no plumbing fixtures

Professional plumbing services can trace the water’s source and recommend remediation.

5. Water Meter Changes Without Usage Point to Plumbing Issues

A simple meter test can often confirm whether you have a hidden leak. It’s a fast, DIY-friendly method before calling a plumber.

Follow these steps:

Turn off all water usage in the house (including irrigation systems and appliances)
Locate your water meter and record the current reading
Wait 30–60 minutes without using any water
Recheck the meter. If the numbers have changed, water is leaking somewhere in your system

Even a small drip can show up over a short testing window, alerting you to call for leak detection services.

6. Leaks may cause Foundation Cracks or Shifting Floors

Sometimes the signs of a hidden water leak aren’t indoors. Foundation movement, cracking tiles, or shifting flooring can all result from prolonged exposure to moisture beneath the home’s slab.

Water slowly escaping from pipes under the slab can erode soil, compromise footings, and lead to expensive repairs.

Look out for:

Visible cracks in foundation walls or floor slabs
Uneven or sagging sections of flooring
Doors and windows sticking or misaligning over time

This kind of damage can escalate if not addressed. Learn more about how undetected leaks affect your home’s structure here.

7. Low Water Pressure Might Be the Result of a Hidden Pipe Leak

Low water pressure is commonly dismissed as a local supply issue, but it could be more serious when it persists only in your home.

Leaking pipes can divert flow before it reaches your taps, meaning you get a trickle instead of a stream. Over time, this can worsen and affect multiple areas.

You may notice:

Poor flow from taps or showerheads in specific rooms
Reduced pressure only on the hot or cold side
The issue getting worse, not better, over time

A professional plumber can assess your plumbing system for pressure irregularities and identify leaks through pressure testing or thermal imaging.

8. Warm Spots on the Flooring Could Mean a Hot Water Pipe Is Leaking

One of the more subtle signs of a hidden leak is warm floorboards or tiles in unexpected areas. If you walk barefoot and notice heat in places away from underfloor heating or appliances, it could be a hot water leak under the slab.

Watch for:

Isolated warm or spongy sections of flooring
Condensation on floors in non-humid environments
A continuous need to reheat water due to system inefficiency

Thermal imaging technology used by plumbers can quickly confirm and locate this kind of leak without unnecessary excavation.

Book Professional Leak Detection in Tamworth Today

At ACS Plumbing, we detect and repair hidden water leaks with precision. If you’ve noticed any of the signs mentioned above, don’t wait until the damage becomes visible—and expensive. Our licensed plumbers in Tamworth can inspect your property, carry out leak detection, and provide the right repairs to protect your home’s integrity.

Book our leak detection services today. For tailored advice or to book a consultation, get in touch via our contact page.

< Older Post Newer Post >

Why Choose Our Gas Fitters in Tamworth

By ACS Plumbing • September 24, 2025

When you need a gas fitter in Tamworth, you want someone who does the job right, keeps you safe and gives value. That’s exactly what we offer. Our gas fitters are fully licensed, highly experienced in LPG and natural gas work, and committed to current safety standards. We treat each job—big or small—with the same care. Whether installing a gas stove, plumbing a new line, repairing a leak or servicing a heater, you can count on us to deliver reliable, legal work. Here’s what sets us apart: Licensed & insured gas fitters who know local regulations and compliance. Safety first: we perform thorough inspections, flue checks, leak detection and combustion checks. Honest, transparent pricing with no hidden surprises. Fast, responsive service— including emergency repairs when you can’t wait. Quality materials, workmanship, and parts and methods built to last. Clear communication: we explain what’s needed, why, and how we’ll do it so you’re always in the loop. FAQs What types of services do gas fitters provide? Gas fitters in Tamworth handle a wide range of services. They install new gas appliances—like cooktops, heaters, hot water systems or BBQs—connect them safely to gas supplies (natural or LPG), adjust the setups so they work efficiently, and ensure all needed ventilation and flue works are correct. They also repair faults and leaks, perform maintenance and inspections, upgrade or reroute gas lines, conduct safety checks (for example, pressure tests or checking combustion), and ensure everything meets current legal and safety standards. How often should I have my gas appliances serviced? Ideally, gas appliances should be serviced at least once a year by a licensed gas fitter. Annual service helps catch wear and potential hazards (like leaks or poor combustion) before they become serious. For rented properties or certain types of appliances, there may be legal or regulatory requirements about safety checks or compliance certificates (often every 1-2 years). Also, call a service immediately rather than waiting for the next scheduled check anytime you notice warning signs—odd smells, soot, yellow rather than blue flame, strange noises. For more information, contact our team today!