Leak Detection Cost Calculator
Estimate the cost of professional leak detection in Australia, by leak location, detection method and urgency.
Under slab leaks are the most expensive to find and the most expensive to get wrong. Detection is $400 to $900, but the repair choice that follows is the real decision, since cutting the slab to access a pipe can run $2,000 to $6,000 while rerouting the line overhead or through the ceiling is often cheaper and less destructive. Get the repair options priced before you authorise any concrete cutting.
💰 Ways to save
- Do the meter test before you call anyone. Turn off every tap and appliance, note the meter reading, wait thirty minutes and read it again. Movement confirms a leak on your side of the meter, and no movement points to a supply side or drainage issue instead. Arriving at that answer yourself saves the plumber diagnostic time you would otherwise pay for.
- Check whether your water utility offers a leak allowance or concession. Most Australian water authorities have a hidden leak rebate scheme that credits part of an abnormally high bill once you provide a plumber's report and proof of repair within a set window. The report you are paying for anyway is usually the document that unlocks it.
- Ask whether the detection fee is credited against the repair if you proceed with the same plumber. Many operators waive or discount the detection charge when they do the repair, which effectively makes the diagnosis free. Confirm this before booking rather than after, because it is rarely offered unprompted.
- Insist on non-destructive detection first. Acoustic, thermal and tracer gas methods locate a leak without opening anything up, and an operator whose first move is to cut tiles or break slab is guessing at your expense. Ask what equipment they carry before you book, and be sceptical of anyone quoting exploratory demolition as the diagnostic step.
How we estimate this
## Leak detection prices in 2026
Pricing reviewed: June 2026.
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Pricing reviewed June 2026. Indicative Australian costs, not a quote.
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Understanding leak detection costs in Australia
Leak detection prices in 2026
Professional leak detection in Australia in 2026 typically costs $300 to $900 for a standard residential job during business hours. A straightforward accessible leak in a wall or ceiling, located with acoustic equipment and thermal imaging, commonly runs $300 to $550. Under slab detection is $400 to $900 because it takes longer and often needs multiple methods. Pool leak detection runs $400 to $800, and tracer gas work, which is the most sensitive method, sits at the top. Same day service adds around 25 per cent, and after hours emergency callouts run 50 to 100 per cent above standard rates. A written report for insurance purposes is usually a separate $200 to $350.
The methods and when each is used
Acoustic detection uses ground microphones and correlators to hear pressurised water escaping, and it is the workhorse method for pressurised supply lines including under slab. Thermal imaging finds temperature differences where water has tracked through a structure, which makes it excellent for hot water leaks and for mapping how far damage has spread, though it detects the effect rather than the source. Tracer gas involves charging the pipe with a safe hydrogen and nitrogen mix and detecting where it escapes, and it is the most sensitive method, used when acoustic fails or on non pressurised and low flow leaks. CCTV drain cameras are for waste and sewer lines rather than supply. A competent operator carries several and uses them in combination.
Why under slab leaks are different
A leak in a pipe cast into or beneath a concrete slab is the hardest and most consequential case. Detection is harder because the slab masks sound and spreads moisture unpredictably, so a wet patch in one room can originate metres away. Detection typically costs $400 to $900 and can take several hours. More importantly, the repair decision that follows is where the money is. Cutting the slab to expose and repair the pipe means jackhammering, repair, backfill, re-concreting and reinstating flooring, commonly $2,000 to $6,000. Rerouting the affected line overhead through the ceiling or wall cavity avoids the slab entirely and is frequently cheaper and less disruptive. Have both priced before authorising anything.
Insurance, cause and the report that matters
Australian home insurance generally covers the damage caused by an escape of water but excludes the cost of repairing the pipe that failed. Most insurers also distinguish between a sudden burst, which is covered, and gradual deterioration or long term seepage, which frequently is not. The practical consequence is that the plumber's written report identifying the leak, its cause and its likely duration is the document your claim turns on. Commission it before repair work destroys the evidence, and make sure it includes photographs, the detection method used and moisture readings. Many insurers will also pay for the detection itself as part of a claim, so ask before you assume it is out of pocket.
Signs you have a leak and what to check first
The clearest test is the water meter. Turn off every tap and appliance, note the reading, wait thirty minutes and read again. Any movement means water is escaping on your side of the meter. Beyond that, the common signs are a bill that has jumped without a change in usage, damp or discoloured patches on walls, floors or ceilings, a musty smell, unexplained warm spots on a floor which indicate a hot water line under slab, reduced water pressure, the sound of running water when nothing is on, and lawn or garden that is unusually green in one patch over a service line. Doing this triage yourself shortens the plumber's diagnostic time.
Water utility rebates and concessions
Most Australian water authorities operate a hidden leak allowance or concession scheme, which credits part of an abnormally high bill where the leak was genuinely concealed and was repaired promptly once discovered. The conditions vary between utilities but generally require a licensed plumber's report identifying the leak, evidence of repair within a defined period, and an application within a time limit of the bill. The amounts can be substantial on a large leak. Since you are already paying for detection and repair, ask the plumber to write the report in the form your utility requires, and lodge it promptly rather than discovering the deadline after it has passed.
Choosing an operator and what to ask
Ask what detection equipment they actually own, since a company that only carries a moisture meter is not doing leak detection in any meaningful sense. Confirm the fee structure, whether it is a fixed detection fee or hourly, and whether it is credited against the repair if you proceed with them. Ask whether a written report is included or extra. Confirm they are a licensed plumber in your state, because the repair will require one regardless. And be direct about non destructive methods, since the operator's first instinct should be to locate the leak with equipment, not to start opening walls and floors at your expense.
Frequently asked questions
How much does leak detection cost in Australia?
Typically $300 to $900 for a standard residential job in business hours in 2026. An accessible wall or ceiling leak is $300 to $550, under slab detection $400 to $900, and pool leak detection $400 to $800. Same day adds around 25 per cent and after hours emergency work 50 to 100 per cent. Insurance reports are usually a separate $200 to $350.
How do I know if I have a hidden leak?
Use the meter test. Turn off every tap and appliance, note the reading, wait thirty minutes and read again. Movement confirms water escaping on your side of the meter. Other signs are an unexplained bill jump, damp patches, a musty smell, warm spots on the floor from a hot water line, and a patch of unusually green lawn over a service line.
Will insurance cover a leak?
Most Australian home policies cover the water damage but exclude repairing the pipe that failed, and many distinguish a sudden burst, which is covered, from gradual deterioration, which often is not. The plumber's written report identifying the cause is what the claim turns on, so commission it before repair work destroys the evidence.
Why is an under slab leak so expensive?
Detection is harder because concrete masks sound and spreads moisture unpredictably, so it takes longer and often needs multiple methods. The bigger cost is the repair. Cutting the slab, repairing, re-concreting and reinstating flooring runs $2,000 to $6,000, while rerouting the line overhead often costs less. Price both before authorising any concrete cutting.
What detection methods are used?
Acoustic microphones and correlators for pressurised supply lines, thermal imaging for hot water leaks and mapping how far damage has spread, tracer gas for the hardest cases where acoustic fails, and CCTV cameras for waste and sewer lines. A competent operator carries several and combines them rather than relying on one.
Can I get money back from my water utility?
Often yes. Most Australian water authorities run a hidden leak allowance that credits part of an abnormally high bill where the leak was concealed and repaired promptly. It generally requires a licensed plumber's report, proof of repair within a set period and an application within a time limit, so ask the plumber to write the report in the form your utility requires.
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