Basic detection, $200–$400
Straightforward jobs: a limited pipe run, good access, the leak confirmed and marked.
Non-Invasive Leak Detection
Find That Leak
Fast Across
Seven Hills
The water bill knows something you don’t. Somewhere under a slab or behind a wall in Seven Hills, a pipe is quietly feeding the ground, and finding it with instruments instead of a jackhammer is the difference between lifting three tiles and gutting a bathroom. We locate to centimetres, then repair through one deliberate hole.
- Licence 368473C, fully insured
- Acoustic, thermal & pressure instruments
- One crew: finds it, then fixes it
How You Find A Leak Without Demolition In Seven Hills
A concealed leak cannot keep all three of its secrets. It makes a sound, pressurised water escaping sings in frequencies acoustic gear tracks along the pipe. It changes temperature, the wet path, or the warm plume of a leaking hot line, paints itself across thermal imaging. And it loses pressure, isolate the pipework section by section against a gauge, and the guilty run confesses while the innocent ones hold steady.
One signal narrows it; three signals convict. Where the readings intersect we mark the surface, and that mark is routinely metres from where instinct says to dig, especially under Seven Hills’s renovated homes, where pipe runs wander in ways no drawing ever recorded. Every centimetre of accuracy is a tile that stays on the floor.
Shower recesses: the most common leak in any block
Failed waterproofing in a shower is the single most frequent source of inter-lot water damage in strata, and it rarely presents as a leak at all, it presents as a damp patch on a neighbour's ceiling months after the membrane gave up.
The suburb’s townhouse and duplex complexes share drainage that blocks from combined waste and is easy to overload.
It is worth ruling in or out early because it is a building repair rather than a plumbing one, and the process for approving and funding it is different. Flood testing the recess is inexpensive and definitive.
Retaining walls, terraces and the services behind them
Many Seven Hills homes date from the postwar boom and still run brittle clay lines that crack with age and let roots and soil in.
Sloping blocks are full of retaining structures, and pipework often runs behind or beneath them because there was nowhere else to put it. A leak in that position saturates backfill, and saturated backfill is what makes retaining walls move.
Water showing at the base of a wall is worth treating as urgent even when the volume looks trivial. The plumbing repair is small compared with what the wall costs.
When a drain leak undermines itself
A cracked earthenware line leaking into its own trench washes out the bedding supporting it. Losing support, the pipe sags; sagging, it holds water; holding water, it collects solids and eventually blocks.
Which is why a drain that has begun to block regularly and a drain that is leaking are frequently the same drain at different stages. Finding it early is considerably cheaper than finding it once it has collapsed.
Whose leak is it in an apartment?
Seven Hills (postcode 2147) sits in the heart of Western Sydney, bordered by Blacktown, Toongabbie, Kings Langley and Lalor Park. A mix of postwar homes and newer townhouse developments means its drains face everything from tree roots to shared-line blockages, and we know them well.
The technical question and the financial question have different answers, and both need settling. Pipework serving only your lot is yours; risers, mains and common-property lines belong to the owners corporation.
A leak detection report that names the line, the lot and the direction of travel is what turns a dispute into a decision. That is what we write, because a description of where the water appeared settles nothing.
Smell as evidence
A persistent sewer smell around a property with no obvious source is worth investigating properly. It usually means either a dry or failed trap, or a break in a line venting where it should not.
A smoke test finds both quickly, introduce smoke into the system and watch where it emerges. It is unglamorous, cheap, and conclusive in a way that sniffing around is not.
The meter test: do this before you call anyone
It is free, it takes an hour, and it settles whether you have a leak at all. Turn off every tap and appliance that uses water, then read your meter, including the smallest dial or digits.
Come back an hour later without using anything. If the reading has moved, water is leaving the property somewhere. If it has not, whatever you are seeing is not a pressurised leak, and that rules out a large and expensive category before you spend anything.
How a leak is actually found
Detection is a process of elimination, not a single instrument. Isolate sections and watch the meter to establish which line is losing water. Listen along it with acoustic equipment for the sound pressurised water makes escaping.
Where that is inconclusive, plastic pipe, deep runs, noisy ground, tracer gas is introduced into the isolated line and detected at the surface. Thermal imaging helps on hot water lines and under floors.
What it costs in Seven Hills
Typical first hour, $300–$500
The standard concealed-leak hunt with the full kit on site, acoustic, thermal, pressure testing.
Extended tracing, $100–$250/hr after
Long pipe runs, poor access or multiple leaks add gauge-and-listen time past the first hour.
Hard-to-access leaks, up to ~$900
Deep slab lines and complex multi-storey tracing sit at the top of the Sydney range.
The repair, priced on what we find
Detection tells you exactly what the repair involves, so the repair quote is built on evidence. One crew does both, no handover, no second call-out fee.
The comparison to hold onto: exploratory demolition costs more than detection before its first guess is even wrong. Figures here are indicative of the 2026 Sydney market rather than a quote from us, you get your own number as a fixed price before any work starts.
How The Hunt Runs
Step 01
Step 01
Verify The Leak Exists
Meter protocol, bills, history. If the evidence says no supply leak, you hear that for free, not a finding fee for nothing.
Step 02
Convict One Line
Section-by-section pressure isolation, hot against cold, run against run, until exactly one line owns the loss.
Step 03
Mark The Centimetres
Thermal and acoustic sweeps along the guilty run until the signals stack on one spot. That mark is where, and only where, we open.
Step 04
One Hole, Done
Access at the mark, section repaired, pressure re-tested, surface closed. A run in terminal condition gets reroute numbers before, not after.
The Dial Moved, Didn’t It?
Then it is real, running, and billing you daily. Detection this week beats discovery through a ruined floor next month.
A standard detection visit generally runs $350-$650 depending on the size of the property and how much isolating is involved. Tracer gas or extensive thermal work sits above that. Market figures for 2026, not a quote, and if the meter test says there is no leak, you are told that rather than sold the rest of the process.
It is elimination, not one instrument. Isolate sections and watch the meter to find which line is losing water, then listen along it with acoustic equipment for the sound escaping water makes. Where that is inconclusive, tracer gas is introduced into the isolated line and detected at the surface.
Because excavation is where the money goes, and water rarely surfaces where it escapes. The plumbing repair on a typical service leak is minor; getting to it is most of the cost, and getting to the wrong place is all of the cost with none of the benefit.
Very commonly. Failed waterproofing in a shower recess is the single most frequent source of inter-lot water damage in strata, and it presents as a damp ceiling patch months after the membrane gave up. Flood testing the recess is inexpensive and definitive, and it is a building repair, not a plumbing one.
Uphill of where you see it. On sloping ground water follows the easiest path underground until something stops it, so it can emerge metres away and always further down. We correlate uphill from the symptom rather than digging at the evidence.
Yes, and it is easy to miss. A cracked drain leaks into the ground continuously without affecting the meter, without a pressure drop, and often with no symptom inside the house. It is found with a camera rather than acoustics, a different method from a pressure leak.
If you are low on a slope, quite likely. Mains pressure rises as elevation falls and properties at the bottom of a hill often sit at the top of the acceptable range. A pressure test costs little and a limiting valve costs little more, the cheapest leak prevention available.
Pinpoint The Leak This Week In Seven Hills
Instruments, a mark on the floor, one hole, one fix: and the meter finally standing still.
