Water leak detection on the Gold Coast: the complete 2026 homeowner's guide

This is the hub page for everything to do with finding a water leak in a Gold Coast home. We have separate deep-dives on a couple of specific topics, our slab leak detection guide for leaks under a concrete floor, and our smart leak detection guide for the sensors and auto-shutoff devices that catch a leak the moment it starts. This page is the big-picture version: how to tell you have a leak at all, how to narrow down what kind it is, and how the leak gets found and fixed.

Read it start to finish if you suspect something, or jump to the section you need.

Why hidden leaks are worse on the Gold Coast

Every hidden leak wastes water and threatens your home. A few things about living here make ours worse than average, and they are worth understanding before we get into the signs.

• Older coastal homes corrode from the inside. A lot of Gold Coast homes from the 1970s through the 1990s were plumbed in copper. Copper is excellent pipe, but decades of water chemistry plus our salt-laden coastal air slowly eats it from both sides. The result is the classic pinhole leak: a tiny weeping hole that drips for months before anyone notices. We see them in walls, in ceilings, and under slabs.
• Slab-on-ground construction hides leaks under your feet. Most Gold Coast homes are built on a concrete slab with the water pipes running through or under it. When a pipe under the slab fails, the water has nowhere obvious to go, so it tracks sideways through the ground or up through the concrete and can run undetected for a very long time. That is a whole topic on its own, covered in our slab leak guide.
• High water table and salt. Canal-front and low-lying suburbs sit on a high water table, and underground service lines in salty, damp soil corrode faster. Yard leaks on the supply line between the meter and the house are common.
• Humidity grows mould fast. This is the one that costs people the most. In our climate, a small leak inside a wall cavity or under a vanity does not just waste water, it creates the warm, damp, dark conditions mould loves. A leak you cannot see can become a mould problem you can smell within weeks.

The takeaway: do not wait and see with a suspected leak here. Time works against you faster than it does in a dry climate.

The warning signs of a hidden water leak

Leaks announce themselves if you know what to look for. If you tick more than one of these, treat it seriously. There is a shorter version of this checklist on our how do I know if I have a water leak page, but here is the full picture.

An unexplained jump in your water bill

This is the single most common way people find a hidden leak. Your usage has not changed, nobody is filling a pool or running extra irrigation, but the bill is noticeably higher than the same quarter last year. A constant slow leak adds up to thousands of litres over a billing period. If your bill has climbed for no reason you can explain, something is using water that you are not.

Damp patches, staining or mould that keeps coming back

Look for discoloured patches on walls or ceilings, paint that is bubbling or blistering, skirting boards that feel soft, a warped section of floor, or a musty smell in a particular room. Mould that you clean off and that keeps returning in the same spot is a strong sign of an ongoing moisture source behind the surface, not just bathroom humidity.

The sound of running water when nothing is on

Stand still in a quiet house with all taps off and listen. A faint hiss, trickle or running-water sound in a wall, under the floor, or near the meter often means a pressurised supply pipe is leaking. This is one of the most reliable signs of a pressure-side leak.

A warm spot on the floor

If part of your slab floor or tiles feels warm underfoot for no reason, you may have a hot water line leaking under the slab. Heated water escaping under the concrete warms the floor above it. A warm patch that does not match where the sun hits is worth investigating.

Dropping or weak water pressure

If your pressure has gradually dropped across the whole house, water may be escaping before it reaches your taps. A leak on the main supply line bleeds off pressure. (Pressure problems have other causes too, but combined with any other sign on this list, a leak moves up the list.)

A water meter that ticks over with everything off

This is the closest thing to a definitive test, and you can do it yourself. If every tap and appliance in the house is off and your water meter is still moving, water is going somewhere it should not. That brings us to the test itself.

The DIY water meter test, step by step

Before you call anyone, you can confirm whether you actually have a leak in about an hour. It costs nothing and the result tells us a lot. Here is exactly how to do it.

1. Turn off every water-using thing in the house. All taps off, washing machine and dishwasher not running, ice maker off, nobody about to flush a toilet. If you have irrigation or a pool auto-fill, make sure they are not on a timer that will trigger mid-test.
2. Find your water meter and read it. On most Gold Coast properties the meter is in a small box near the front boundary or footpath. Write down the full reading, including the small dials or the last digits that measure fine usage. Many meters also have a tiny flow indicator (a small red or black triangle or star) that spins when water is moving, note whether it is moving.
3. Wait without using any water. Leave it 30 minutes to two hours. The longer you can leave it with genuinely zero usage, the clearer a small leak shows up. The easy version is to read it last thing at night and again first thing in the morning before anyone uses a tap.
4. Read the meter again. If the numbers have moved or that little flow indicator is turning with everything off, you have a leak somewhere on your side of the meter. If nothing has moved at all, you very likely do not have a continuous leak (though an intermittent one, like a toilet that occasionally cycles, can still hide from this test).

One useful narrowing step: if the test shows movement, turn off the isolation valve where the water main enters your house (often near the front of the house or at the meter), leaving the meter on. Repeat the read. If the meter stops moving once the house is isolated, the leak is inside or under the house. If it keeps moving with the house isolated, the leak is on the underground service line between the meter and the house, out in the yard. That one piece of information saves time and money when we arrive.

The meter test tells you whether you have a leak and roughly which side it is on. It does not tell you the exact spot inside a wall or under a slab. That is where professional detection comes in.

The types of leak we find on the Gold Coast

Not all leaks are the same problem. Knowing the categories helps you understand what the detection and repair will involve.

Supply-side (pressure) leaks

These are on the pressurised pipes that bring clean water to your taps. Because they are under constant pressure, they waste water around the clock and show up clearly on the meter test. Pinhole leaks in old copper are the classic Gold Coast example. A bad one becomes a burst, which is an emergency, see our burst pipe repairs page if water is actively flowing.

Drainage-side leaks

These are on the waste and sewer pipes that carry water away. They are not pressurised, so they leak only when something is draining, which makes them harder to catch on a meter test and means they often show up as damp ground, smell, or undermined paving rather than a high bill. Cracked or root-invaded drains and failed pipe joints are common, and a drain camera is usually the right tool.

Under-slab leaks

A supply or drainage pipe failing beneath the concrete slab. These are the ones that cause warm floor spots (hot line), tracking damp through tiles, and slow, expensive damage because they are completely out of sight. We cover these in full in the slab leak detection guide, because finding the exact spot without jackhammering the whole floor is the entire game.

In-wall leaks

A pipe leaking inside a wall cavity, often feeding a shower mixer, a vanity, or a concealed toilet cistern. These are the fastest to cause mould in our climate because the cavity stays warm and dark. Staining, bubbling paint and a musty smell on one wall are the usual giveaways.

Underground yard / service-line leaks

A leak on the buried pipe between your water meter and the house. The meter keeps ticking even with the house isolated, and you may notice an unusually green or boggy patch of lawn that never dries out. Salty, damp coastal soil makes these more common here.

Pool plumbing leaks

A leaking pool return line, suction line or auto-fill valve can quietly raise your water bill and is easy to mistake for a house leak. A stuck-open auto-fill is a frequent culprit. If the meter moves but the house is fine, the pool plant is worth a look.

Roof vs plumbing leaks

A ceiling stain after rain is usually a roof or flashing problem, not a plumbing leak. A ceiling stain that appears in dry weather, or that grows steadily regardless of rain, points to plumbing. The timing relative to the weather is the simplest way to tell them apart before anyone goes into the roof space.

How professional non-invasive leak detection works

Here is the part that matters most, because it is where people either save money or waste it. The old way of finding a hidden leak was to guess where it was and start cutting open walls or breaking up the slab until you found it. That is destructive, slow, and frequently wrong on the first try, which means more cutting, more patching and more cost. It also means a big repair bill even when the leak itself was small.

Modern leak detection is non-invasive. We use specialised gear to pinpoint the leak through the wall or slab before anything gets opened up, so the only thing we cut into is the small section that actually needs fixing. The skill is in combining several methods, because no single tool finds every leak. Here is the toolkit.

In practice we layer these. A typical job might start with a pressure test to confirm the leak is on the supply side, then acoustic listening to find the rough area, then thermal imaging and moisture mapping to pin it down to within a small zone before anything is opened. For drainage problems the camera does the heavy lifting. The acoustic side has a bit more detail on our how does acoustic leak detection work page if you want to understand that method specifically.

The point of all of it is the same: find the exact spot first, then make one small, precise repair instead of a large destructive one.

What leak detection costs on the Gold Coast

Honest answer: it varies, and you should get a quote rather than trust a flat number off the internet. As a realistic guide, a professional non-invasive leak detection service call on the Gold Coast commonly runs roughly $200 to $500 and up, depending on how hard the leak is to find and which equipment the job needs. A straightforward leak found quickly with acoustic listening sits at the lower end. A tricky intermittent leak that needs tracer gas, thermal imaging and a camera survey across a large or complex home sits higher.

That cost is for finding the leak. The repair is separate and depends entirely on what we find, where it is, and how accessible it is. A pinhole in an accessible wall is a quick fix; an under-slab line is a bigger job. We will give you the repair price once we know exactly what we are dealing with, which is the whole reason detection comes first.

It is worth saying plainly: paying for detection almost always saves money overall, because the alternative is guessing and cutting, which routinely costs more in unnecessary damage and patching than the detection ever would. There is a fuller pricing breakdown on our how much does leak detection cost on the Gold Coast page.

When to DIY and when to call

You can and should do the easy diagnostics yourself. Where it stops being a DIY job is anything inside a wall or under a slab, or anything that needs to be cut open or repaired.

Fine to do yourself

• The water meter test above, including isolating the house to work out which side the leak is on.
• A toilet dye test for a silently running cistern: a few drops of food colouring in the cistern, wait 15 minutes without flushing, and if colour appears in the bowl the flush valve is leaking.
• Checking visible fittings under sinks, behind the toilet and at the hot water unit for obvious drips.
• Tightening a clearly loose tap connection (gently, do not force it).

Time to call us

• The meter ticks over with everything off and you cannot see the source.
• Damp patches, returning mould, a musty smell, or a warm spot on the floor.
• The sound of running water inside a wall or under the floor.
• Any leak you suspect is inside a wall, in the ceiling, or under the slab.
• A water bill that has jumped with no explanation.

If water is actively flowing or pouring rather than slowly leaking, do not wait for the diagnostic stage, that is an emergency. Shut off the water at the meter and call our emergency plumbing line straight away.

Catching the next leak before it starts

Once you have dealt with one hidden leak, it is natural to want to avoid the next one. The most effective prevention for a leak-prone home, particularly older copper, holiday lets, or a premium fitout you cannot afford to flood, is a smart leak detection system that watches your water flow and can shut the water off automatically the moment something is wrong. That is a whole topic, and we have written it up in detail in our smart water leak detection guide. If your home ticks any of the higher-risk boxes, it is worth a read.

What we do

We find leaks without wrecking your house. We bring the full kit, acoustic ground microphones, thermal imaging, tracer gas, moisture meters, pressure testing equipment and a drain camera, and we use whichever combination the job calls for to pinpoint the leak before we open anything. Then we fix it, from a pinhole repair through to under-slab work, and we give you a clear written quote on the repair once we know exactly what is there.

If you have done the meter test and it is ticking, or you have any of the warning signs above, get in touch. Book online through our contact page or call us on 0472 657 042. The sooner a hidden leak is found here, the less water it wastes and the less chance it has to turn into a mould and damage problem.