Leak Detection Specialist or Plumber: Who Should You Call First?
When water shows up where it shouldn't, most people search for a plumber. It makes sense: water, pipes, plumber. But every day our technicians walk into homes and apartments where the same story has already played out. A plumber came. Then another. Grout was redone, a pipe was replaced, maybe a shower was ripped out. Thousands of dollars later, the stain is still growing.
The problem usually isn't the quality of the repair. It's that nobody proved where the water was coming from before the work started. This guide explains why finding a leak and fixing a leak are two different jobs, when to call a plumber, when to call a leak detection specialist first, and the questions to ask before anyone opens a wall or quotes a renovation.
Finding a leak and fixing a leak are two different jobs
A good plumber is trained to install and repair. Finding a hidden leak is a diagnostic job, closer to what a doctor does before an operation. Water rarely appears where it gets in. It travels along pipes, through concrete slabs, under tiles and down wall cavities, and can surface metres away from the source. A wet ceiling might be a shower, a balcony, a roof flashing or a pipe in the slab above. Each needs a completely different repair.
Without the right equipment and testing, the person on site has to make an educated guess. When the guess is wrong, you pay for the repair, the leak continues, and you pay again for the next guess.
Why the "guess and replace" approach gets so expensive
The pattern we hear from customers is remarkably consistent:
The shower is regrouted and resealed. The leak comes back after the next few weeks of use.
A section of pipe is replaced, or a whole line is rerouted. The water keeps coming.
Someone recommends a full bathroom or balcony rebuild "to be safe", often a five-figure job.
The insurer asks for the cause of the damage, and nobody can give one, so the claim stalls.
Each step on its own can sound reasonable. Together they can cost more than finding the leak properly would have, many times over. And a rebuild that doesn't address the real cause, such as a leaking pipe behind a wall or water coming from the unit above, won't stop the damage.
A real example from one of our recent jobs
A tenanted apartment in Melbourne's south-east had damp carpet and lifting floorboards along an external wall every time it rained heavily. Over several years, the building's plumbers had been called out a number of times. Each time the problem was put down to sealing, the tenant was told to keep an eye on it, and at one point a carpenter resealed the joins. The water kept coming back. As the owner put it, the investigation so far had involved running water over the area for a few hours, but no thermal imaging or specialised leak detection.
Our technician used thermal imaging and moisture mapping to see where the water sat in the floor and wall, then ran controlled tests one area at a time: a dye flood test of the terrace, hot water testing of the wall joints and of the window frame. None of them reproduced the leak. That evidence ruled out the unit's own terrace, waterproofing, expansion joints and window. It pointed to the level above and common property instead, which changed who needed to act and where the next round of testing had to happen.
No walls were opened on a guess and nothing was rebuilt that didn't need to be. Instead the owner and the body corporate got a written report showing what had been tested, what had been ruled out and where the water was most likely coming from.
What a leak detection specialist actually does
A leak detection specialist's job is to prove the source before anything is repaired. Depending on the leak, that can include:
Meter and pressure testing to confirm whether a water line is leaking, and which one.
Acoustic ground microphones to listen for the sound of water escaping from a pressurised pipe under slabs, paths and gardens.
Tracer gas, a safe hydrogen and nitrogen mix that rises through soil, concrete and tiles at the exact leak point, used for pipes that are hard to hear.
Thermal imaging and moisture mapping to show how far the water has spread behind plaster, tiles and floors.
Flood, dye and water testing of showers, balconies, windows and roofs, one part at a time, until the leak is reproduced.
The result is a marked location on site and a written report with photos and readings. That report tells your plumber, builder, waterproofer or body corporate exactly what to fix, and gives your insurer the evidence of cause it normally asks for.
What we see across thousands of jobs
We carry out more than 5,000 leak detection jobs a year across Melbourne, Sydney, Brisbane and the Gold Coast. When we reviewed 245 of our leak reports, 58% found more than one cause. That's why fixing the first likely suspect so often fails: even when it is one of the problems, it isn't the only one.
When to call a plumber first, and when to call a specialist
Call a plumber first when you can see the problem: a dripping tap, a burst pipe you can see spraying, a blocked drain, a broken toilet or a hot water system that has stopped working.
Call a leak detection specialist first when:
You can see water damage but not where it's coming from.
Your water meter moves with every tap off, or your water bill has jumped.
A leak keeps coming back after a repair.
Someone is recommending opening walls, jackhammering a slab or rebuilding a shower or balcony to "find" the leak.
You need evidence of the cause for an insurance claim, a landlord, or a body corporate or strata dispute.
Questions to ask before anyone opens a wall or quotes a rebuild
How will you confirm the source before the work starts?
What testing will you do, and will you show me the results?
Is this quote to find the leak, or to fix what you think it is?
Will I get a written report with photos and readings that my insurer will accept?
How will we know the leak has stopped after the repair?
If the answers are vague, get the leak found and documented first. It usually costs a fraction of the repair you're being quoted.
Plumbers and specialists work best together
This isn't about plumbers versus leak detectors. Many plumbers, builders and property managers call us in when a leak can't be found, because it means they dig once, in the right place, and the repair works the first time. Our first visit is about finding the leak: we mark it, explain the cause and give you a report. Your own plumber can repair it from the report, or if you'd like us to fix it, we'll quote the repair and return at another time to complete it, often with trusted independent trades.
What it costs
Leak detection starts from $398 inc. GST for the first hour on site in metro Melbourne, Sydney, Brisbane and the Gold Coast, with a written report included. Found or you don't pay.* *If we can't find the leak, you don't pay for the inspection. Ask for details when you book or read our guarantee terms. See prices for all areas.
Before you spend another dollar on repairs that might not stop the water, call 1300 346 353, 24/7, or book online.
Frequently asked questions
Is a leak detection specialist the same as a plumber?
No. A plumber installs and repairs plumbing. A leak detection specialist uses testing equipment such as pressure testing, acoustic listening, tracer gas and thermal imaging to find and prove where a hidden leak is, then documents it in a report so the right trade can fix the right spot.
Why does my leak keep coming back after it was repaired?
Usually because the repair fixed a likely suspect rather than the confirmed source, or because there is more than one cause. In a review of 245 of our leak reports, 58% found more than one cause.
Will my insurance pay for leak detection?
Many home and building policies cover finding a hidden leak that has caused damage, often called trace and access cover. Check your policy. Our report records where the water came from and why, which is what insurers normally ask for.
Do you do the repairs as well?
Yes, if you'd like us to. Our first visit is about finding the leak: we mark it, explain the cause and give you a report. Many plumbers, builders and property managers then do their own repairs. If you want us to fix it, we'll quote the repair and return at another time to complete it, often with trusted independent trades.
